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SECTION 1: ONCOLOGY

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A) Principles Underlying Non-Surgical Treatment of Cancer

1. Radiotherapy

• Based on the principle that ionizing radiation damages DNA (single- and double-strand breaks), leading to cell death
• Rapidly dividing cells (tumor cells) are more radiosensitive than slow-dividing normal cells
• The 5 R's of Radiobiology: Repair (of sublethal damage), Redistribution (of cells through cell cycle), Repopulation (of normal tissue), Reoxygenation (of hypoxic tumour cells), and Radiosensitivity
• Fractionation spares normal tissue while delivering a lethal cumulative dose to tumor
• Types: External beam (EBRT), Brachytherapy, IMRT, Stereotactic radiosurgery (SRS/SABR)

2. Chemotherapy

• Acts on rapidly dividing cells - most agents are cell-cycle specific or non-specific
• Principles: Log-kill hypothesis - each dose kills a fixed percentage (not number) of cells; hence multiple cycles are needed
• Gompertzian growth kinetics: tumors grow rapidly when small but slow as they enlarge; this means smaller tumors are most sensitive to chemotherapy (the basis for adjuvant chemo)
• Drug classes: Alkylating agents (cross-link DNA), Antimetabolites (S-phase), Topoisomerase inhibitors, Mitotic spindle poisons (Vinca alkaloids, Taxanes), Anthracyclines
• Combination regimens exploit different mechanisms and reduce resistance

3. Hormonal Therapy

• Applicable to hormone-receptor positive tumors (breast, prostate, endometrial)
• Removes the growth stimulus: oophorectomy/orchiectomy, LHRH analogues, anti-estrogens (Tamoxifen), aromatase inhibitors, anti-androgens (Bicalutamide, Enzalutamide)

4. Immunotherapy

• Checkpoint inhibitors (anti-PD-1/PD-L1, anti-CTLA-4) release brakes on T-cell killing of tumour cells
• CAR-T cell therapy engineers patient T-cells to recognize tumor antigens
• Monoclonal antibodies (Trastuzumab for HER2, Bevacizumab for VEGF) target specific molecular drivers

5. Targeted Therapy (see below)

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B) Cancer Cachexia

Epidemiology

• Occurs in ~50% of cancer patients
• Most common with gastrointestinal, pancreatic, and lung cancers
• Responsible for ~30% of cancer deaths

Clinical Features

• Extreme weight loss (>5% body weight in 6 months, or >2% with BMI <20)
• Muscle atrophy, fatigue, anorexia, anemia, edema
• Impaired wound healing, poor treatment tolerance
• Death often from diaphragmatic and respiratory muscle atrophy

Pathogenesis

• Inflammatory cytokines: TNF-alpha, IL-1, IL-6 are key drivers. They:
  • Increase muscle protein degradation via ubiquitin-proteasome pathway
  • Promote lipolysis
  • Suppress appetite via hypothalamic mechanisms
• GDF-15 (Growth Differentiation Factor-15): secreted by tumor cells and macrophages; binds GFRAL receptor in brainstem, suppressing appetite - promising therapeutic target
• Tumor factors (PIF - Proteolysis Inducing Factor, LMF - Lipid Mobilizing Factor) directly cause muscle and fat breakdown
• Reduced caloric intake compounds the problem

Management

• Nutritional support: High-protein, high-calorie diet; enteral/parenteral nutrition
• Pharmacological:
  • Megestrol acetate / Medroxyprogesterone (appetite stimulants)
  • Corticosteroids (short-term appetite improvement)
  • Omega-3 fatty acids (EPA) - modest benefit
  • Anamorelin (ghrelin receptor agonist) - approved in Japan
  • Anti-inflammatory agents (NSAIDs, thalidomide)
• Exercise: Resistance exercise preserves muscle mass
• Treat underlying tumor aggressively - most effective treatment

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C) Oncoplastic Breast Surgery

Definition

Techniques

• Therapeutic mammoplasty (reduction/mastopexy pattern)
• Lateral/medial tissue advancement (Batwing, Hemi-Batwing)
• Round block (periareolar) technique
• Superior pedicle/inferior pedicle procedures

• Local flaps: Lateral Intercostal Artery Perforator (LICAP), Lateral Thoracic Flap, Thoracoepigastric flap
• Regional flaps: Latissimus dorsi mini-flap
• Free flaps (for large defects)

Indications

• Breast-conserving surgery (BCS) where standard lumpectomy would cause unacceptable cosmetic result
• Tumors in cosmetically challenging locations (lower pole, NAC, medial)
• Large tumor-to-breast ratio (>20% volume resection anticipated)
• Multifocal disease amenable to wide excision
• After neoadjuvant chemotherapy (downstaging allows BCS)
• Patient preference to avoid mastectomy

Complications

• Immediate: Hematoma, seroma, infection, wound dehiscence, fat necrosis
• Late: Altered nipple sensation, scar contracture, asymmetry, NAC necrosis
• Oncological: Margin involvement (requires re-excision or mastectomy), delays in adjuvant radiotherapy, difficulty in surveillance imaging
• Specific to reduction patterns: Delayed wound healing in irradiated field

Current Status

• Widely accepted globally; allows resection of up to 30-50% breast volume with acceptable cosmesis
• Level I technique OPS (small resections, <20% volume) vs. Level II OPS (large resections, >20%)
• Oncological safety equivalent to standard BCS in terms of local recurrence rates
• Must be planned preoperatively with multidisciplinary team
• Contra-lateral symmetrisation surgery often required
• Evidence supports combining with SLNB; post-OPS radiotherapy planning must account for altered breast anatomy
• Growing role of pre-operative 3D simulation for planning

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D) Targeted Therapy in Cancer Treatment

Mechanisms and Key Agents

Advantages

• More selective, fewer systemic side effects compared to conventional chemo
• Can be tailored by molecular profiling (precision oncology)
• Oral agents allow outpatient treatment
• Effective in chemotherapy-resistant tumors

Limitations

• Expensive; limited availability in low-resource settings
• Requires biomarker testing (companion diagnostics) before use
• Resistance develops (primary and acquired) - e.g., T315I mutation in CML resistant to Imatinib
• Side effects specific to pathway: rash (EGFR inhibitors), cardiomyopathy (Trastuzumab), hypertension (anti-VEGF), GI perforation (Bevacizumab)

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E) Environmental Causes of Cancer

Classification

• Direct-acting: Alkylating agents, acylating agents (nitrogen mustard, beta-propiolactone) - used in chemotherapy, occupational exposure
• Indirect (procarcinogens requiring metabolic activation):
  • Polycyclic aromatic hydrocarbons (PAH) - tobacco smoke, charred food → lung, skin, bladder cancer
  • Aromatic amines / Azo dyes - occupational (rubber, dye industry) → bladder cancer (aniline dyes)
  • Nitrosamines - smoked/preserved foods → gastric, esophageal cancer
  • Aflatoxin B1 - Aspergillus-contaminated grains → hepatocellular carcinoma
  • Benzene → leukemia
  • Vinyl chloride → hepatic angiosarcoma
  • Asbestos → mesothelioma, lung cancer
  • Arsenic → skin, lung, bladder cancer

• Ionizing radiation: UV (squamous cell/basal cell skin cancers, melanoma via UVA+UVB), X-rays, gamma rays (leukemia, breast, thyroid), nuclear fallout (Hiroshima/Nagasaki data)
• Non-ionizing: UVA/UVB cause pyrimidine dimers in skin cells
• Radon gas: lung cancer (miners, poorly ventilated homes)

• Tobacco: lung, laryngeal, oral, esophageal, bladder, kidney, pancreas
• Alcohol: liver, esophageal, oral, breast cancers
• Obesity: endometrial, breast (postmenopausal), colorectal, gallbladder cancer
• High animal fat diet: colorectal, prostate cancer
• Lack of fiber: colorectal cancer

• Mesothelioma (asbestos) - insulation workers, shipbuilding
• Bladder cancer (aromatic amines) - rubber/dye workers
• Leukemia (benzene) - petrochemical workers
• Nasal sinus cancer (wood dust, leather dust)

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F) Intra-Operative Tissue (Pathological) Diagnosis

1. Frozen Section Biopsy

• Principle: Rapid freezing of tissue (cryostat at -20°C) followed by sectioning, H&E staining, and microscopic analysis within 15-30 minutes
• Uses: Assessment of surgical margins (particularly breast, head & neck), lymph node status (sentinel node biopsy), identification of parathyroid tissue, nature of lesion (benign vs. malignant)
• Accuracy: ~96-98%; certain tumors (fatty tissue, small round cell tumors, calcified tissue) are unsuitable
• Limitations: Artifacts (ice crystal formation), limited special stains, occasional discordance with permanent sections

2. Touch Imprint Cytology (Scrape/Imprint)

• Fresh cut surface of tissue is touched against a glass slide
• Rapid Papanicolaou or H&E stain
• Quick (5-10 min), no special equipment needed
• Useful where frozen section is unavailable; slightly less accurate for margin assessment

3. Fine Needle Aspiration Cytology (FNAC) / Core Biopsy

• Pre- or intraoperative FNAC of a mass
• Cytological diagnosis before definitive excision

4. Sentinel Lymph Node Biopsy (SLNB) Intraoperative Analysis

• Frozen section or imprint cytology of sentinel nodes during surgery
• Guides axillary lymph node dissection decision in breast cancer

5. Radiolabeled Probe / Gamma Probe Intraoperative Assessment

• Detects radioactive tracer in tissue; not strictly pathological but guides resection

6. Rapid Immunohistochemistry

• Some centers perform rapid IHC on frozen sections for hormone receptors, Ki-67, HER2 intraoperatively

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G) Multi-Disciplinary Team (MDT) in Oncology

Definition

Members

• Core team: Surgical oncologist, Medical oncologist, Radiation oncologist, Pathologist, Radiologist
• Extended team: Palliative care physician, Nurse specialist, Psycho-oncologist, Nutritionist/Dietitian, Social worker, Physiotherapist, Genetic counselor, Nuclear medicine physician
• Disease-specific additions: Hepatologist (liver tumors), Gastroenterologist, Plastic surgeon (reconstruction), Neurosurgeon, Gynecologic oncologist

Functions of MDT

• Review all imaging, pathology, and clinical information at MDT meeting
• Make treatment decisions based on evidence-based guidelines
• Coordinate sequencing of multimodal treatment (neoadjuvant → surgery → adjuvant)
• Discuss complex/borderline cases
• Refer to clinical trials
• Provide holistic patient support (psychological, nutritional, rehabilitation)
• Ensure continuity of care

Benefits

• Improved survival outcomes and adherence to guidelines
• Reduced variation in practice; standardizes care
• Better patient satisfaction
• Identifies patients suitable for clinical trials
• Supports education and training of junior members

Concept

• MDT meetings are typically held weekly, with all new cases and complex recurrences discussed before treatment begins
• Tumor boards and MDT meetings are now mandated in many countries and are standard of care
• Digital MDT meetings (tele-oncology) expand access

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H) Criteria and Advantages for Cancer Screening

Wilson and Jungner Criteria (WHO, 1968) - Still the Standard

1. The condition should be an important health problem
2. There should be an accepted treatment for patients with recognized disease
3. Facilities for diagnosis and treatment should be available
4. There should be a recognizable latent or early symptomatic stage
5. There should be a suitable test or examination (sensitive, specific, acceptable)
6. The natural history of the condition should be adequately understood
7. There should be an agreed policy on whom to treat as patients
8. The cost should be economically balanced to possible expenditure
9. Case-finding should be a continuing process

Advantages of Screening

• Detection at early (potentially curable) stage
• Reduced mortality from the specific cancer
• Less aggressive treatment needed at early stage (organ preservation)
• Reduced morbidity and healthcare costs long-term
• Reassurance for screen-negative individuals

Screening Methods

• Mammography: Gold standard; 2D, now 3D (tomosynthesis); every 1-2 years from age 40-50 (varies by guideline)
• Clinical Breast Examination: Annually from age 25-40 (especially in low-resource settings)
• Breast Self-Examination: Awareness tool; limited sensitivity
• MRI: For high-risk (BRCA mutation carriers, lifetime risk >20%)

• Fecal Occult Blood Test (FOBT) / Fecal Immunochemical Test (FIT): Annual; non-invasive
• Colonoscopy: Gold standard; every 10 years; detects polyps (adenoma-carcinoma sequence)
• CT Colonography (Virtual Colonoscopy): Every 5 years; no polypectomy capability
• Flexible Sigmoidoscopy: Every 5 years (covers distal colon only)
• Stool DNA test (Cologuard): Every 3 years; detects KRAS mutations and methylation

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I) Pathological Changes in Malignant Transformation

Molecular Hallmarks (Hanahan and Weinberg)

1. Sustained proliferative signaling - oncogene activation (RAS, MYC, EGFR)
2. Evading growth suppressors - tumor suppressor loss (p53, Rb, BRCA)
3. Resisting cell death - BCL-2 overexpression, loss of apoptosis
4. Enabling replicative immortality - telomerase reactivation (TERT)
5. Inducing angiogenesis - VEGF upregulation
6. Activating invasion and metastasis - loss of E-cadherin, MMP activation, epithelial-mesenchymal transition (EMT)
7. Reprogramming energy metabolism - Warburg effect (aerobic glycolysis)
8. Evading immune destruction - PD-L1 expression, loss of MHC-I

Morphological Changes

• Nuclear changes: Pleomorphism, hyperchromasia, increased N:C ratio, prominent nucleoli, abnormal mitoses
• Cellular changes: Loss of polarity, variable size and shape, tumor giant cells
• Tissue changes: Invasion of basement membrane (key step), loss of glandular architecture, desmoplastic stroma
• Chromosomal instability: Aneuploidy, deletions, translocations, amplifications
• Epigenetic changes: Promoter methylation of TSGs, histone modification changes

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J) Gompertzian Growth in Oncology

Concept

• Nutrient/oxygen limitation
• Buildup of inhibitory metabolites
• Inadequate neovascularization

Clinical Implications

1. Chemotherapy sensitivity: Small tumors (micrometastases) are in the steep growth phase with highest growth fraction → most sensitive to chemotherapy (basis for adjuvant chemotherapy and dose-dense regimens)
2. Adjuvant therapy rationale: Surgical removal of bulk tumor forces residual micrometastases back to steep growth phase, re-sensitizing them to chemotherapy
3. Neoadjuvant therapy: Downstaging relies on this - while tumor is small enough for rapid growth, chemo kills maximally
4. Norton-Simon hypothesis: Dose-dense chemotherapy (shortening intervals between cycles) exploits Gompertzian re-acceleration after each course
5. Metastasis timing: By the time a primary tumor reaches clinical detection (10^9 cells, 1cm), it may already have shed metastases during its earlier rapid growth phase

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K) Lead Time and Length Bias in Breast Cancer Screening

Lead Time Bias

• Definition: The apparent increase in survival time resulting from earlier detection (advanced diagnosis date), without actual prolongation of life
• In screening, if cancer is detected 2 years earlier by screening vs. symptoms, but the patient dies at the same time, survival from diagnosis appears longer (by 2 years) - this is the "lead time"
• To correct: Compare disease-specific mortality rates between screened and unscreened populations, not survival rates from diagnosis

Length Bias (Length-Biased Sampling)

• Definition: Screening tends to detect slowly growing (less aggressive) tumors disproportionately, because they have a longer detectable preclinical phase ("sojourn time")
• Rapidly growing, aggressive tumors arise and cause symptoms between screening rounds (interval cancers) and are missed by screening
• Thus screened populations appear to have better outcomes partly because they contain more indolent tumors
• This contributes to overdiagnosis - detection of tumors that would never cause clinical harm during a patient's lifetime (e.g., low-grade DCIS)

Overdiagnosis Bias

• Closely related to length bias; screening detects cancers that would never have been symptomatic
• Particularly relevant for thyroid cancer, prostate cancer (PSA screening), and low-grade DCIS in breast screening

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L) HIPEC - Hyperthermic Intraperitoneal Chemotherapy

Definition

Rationale

• Peritoneal deposits have poor systemic drug delivery (peritoneal-plasma barrier)
• Direct peritoneal instillation achieves high local drug concentrations (10-1000x systemic)
• Hyperthermia (42°C) enhances drug penetration, inhibits DNA repair, and has direct cytotoxic effects
• Macroscopic disease is resected by CRS; HIPEC targets microscopic residual disease

Drugs Used (Fischer's Mastery of Surgery)

Indications

1. Established: Pseudomyxoma peritonei, peritoneal mesothelioma
2. Accepted: Colorectal cancer with peritoneal metastases (limited peritoneal carcinomatosis index - PCI)
3. Ovarian cancer: After primary debulking (interval HIPEC) - OVHIPEC trial showed improved survival
4. Gastric cancer with peritoneal disease (selected patients)
5. Selected peritoneal spread from appendix tumors

Contraindications

• High PCI score (>20 colorectal, >20 ovarian) indicating unresectable disease
• Poor performance status (PS ≥ 3)
• Significant co-morbidities (renal, hepatic, cardiac failure)
• Inability to achieve complete cytoreduction (CC-0 or CC-1)

Complications

• Anastomotic leak (most serious - 5-10%)
• Wound infection, dehiscence
• Bowel obstruction
• Hematoma, seroma
• Pleural effusion
• Neutropenia, thrombocytopenia (myelosuppression from absorbed chemotherapy)
• Renal toxicity (cisplatin), hepatotoxicity
• VTE (DVT, PE)
• Prolonged ileus

• Intestinal fistula
• Incisional hernia
• Adhesive obstruction
• Port site metastasis (if laparoscopic)
• Neuropathy (oxaliplatin, cisplatin)
• Disease recurrence

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SECTION 2: SURGICAL INSTRUMENTS & TECHNIQUES

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A) Surgical Blades and Handles

Common Surgical Blades

Knife Handles

• No. 3 handle: Long, slender; fits blades 10, 11, 12, 15 - general surgery
• No. 4 handle: Shorter, wider; fits blades 20, 22, 23 - orthopedic/thoracic
• No. 7 handle: Long, narrow (like extended No.3); for deep cavity work, ENT - fits No. 11, 15
• No. 9 handle: Used in ophthalmology

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B) Wound Dressings - Types and Principles

Classification

• Dry gauze, paraffin gauze (Jelonet), non-adherent dressings (Melolin)
• Principle: Physical barrier; absorb exudate; maintain moist wound environment
• Indications: Clean healing wounds, low exudate wounds

• Hydrocolloids (DuoDERM): Absorb exudate, maintain moisture, promote autolytic debridement
  • Indications: Pressure ulcers, shallow wounds, leg ulcers
• Hydrogels: Donate moisture to dry wounds; rehydrate slough
  • Indications: Dry/necrotic wounds, burns, radiation wounds
• Alginates (Sorbsan, Kaltostat): Derived from seaweed; high absorption capacity; hemostatic; form gel on contact
  • Indications: Highly exudative wounds, infected wounds, cavity wounds
• Foams (Mepilex, Allevyn): High absorbency; thermal insulation
  • Indications: Moderate-heavily exudating wounds, diabetic ulcers

• Negative Pressure Wound Therapy (NPWT / VAC): Foam + sealed dressing + suction at -75 to -125 mmHg
  • Principle: Removes exudate, reduces edema, increases perfusion, promotes granulation
  • Indications: Complex wounds, diabetic foot, post-dehiscence, open abdomen management
• Silver-containing dressings (Aquacel Ag, Mepilex Ag): Antimicrobial; prevent biofilm
  • Indications: Infected or at-risk wounds, burns
• Iodine dressings (Iodosorb, Betadine soaked): Broad-spectrum antimicrobial
• Honey dressings (Medihoney): Antimicrobial, anti-inflammatory, debrides
• Collagen dressings: Promote granulation in chronic wounds
• Biological/Skin substitutes (Integra, AlloDerm): Provide scaffold for skin regeneration
  • Indications: Extensive burns, complex reconstructive wounds

• Compression bandages: Venous ulcers (4-layer bandaging - Charing Cross)
• Antimicrobial barrier dressings: Critical colonization
• Charcoal dressings: Malodorous wounds (fungating tumors)

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C) Suture Materials

Classification

• Natural: Catgut (plain - absorbed 70 days, chromic - 90 days) - no longer widely used
• Synthetic monofilament: Monocryl (Poliglecaprone 25) - absorbed 90-120 days; PDS (Polydioxanone) - absorbed 180 days; excellent for fascial closure
• Synthetic braided/multifilament: Vicryl (Polyglactin 910) - absorbed 56-70 days; Dexon (Polyglycolic acid) - 60-90 days; Vicryl Rapide - 42 days

• Natural: Silk (technically slowly absorbable over years); Cotton
• Synthetic monofilament: Nylon (Ethilon), Prolene (Polypropylene) - permanent; least tissue reaction; ideal for vascular surgery, skin closure
• Synthetic multifilament: Braided Nylon (Nurolon), Polyester (Ethibond, Dacron) - cardiac, vascular

Desirable Characteristics

• High and predictable tensile strength
• Adequate knot security
• Non-allergenic, non-carcinogenic, non-electrolytic
• Easy to handle (good pliability)
• Non-capillary (prevents bacteria tracking - monofilament preferred in infected fields)
• Predictable absorption (for absorbable sutures)
• Minimal tissue reaction
• Sterilizable

Sutures for Key Anastomoses

• Small bowel anastomosis: Vicryl 3-0 or PDS 3-0 (single or double layer), or stapled
• Bilioenteric anastomosis: PDS 4-0 or Vicryl 4-0 interrupted (Roux-en-Y hepaticojejunostomy); 5-0 for pediatric

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D) Principles of Electrosurgery (Diathermy)

Principle

Cutting Mode

• Mechanism: Very high power at low voltage; rapid cell heating → cell water vaporizes → cells explode → tissue is cut
• Effect: Clean incision with minimal lateral thermal damage
• Waveform: Continuous sinusoidal wave
• Spray mode: Low voltage, pulsed wave; wider area vaporization - used for tumor ablation surface treatments

Coagulation Mode

• Mechanism: Lower power at higher voltage; slower cell heating → protein denaturation and coagulation → blood vessel sealing
• Waveform: Pulsed (intermittent) wave - ~6% duty cycle
• Fulguration (spray coagulation): Electrode does not contact tissue; sparks produce superficial char
• Desiccation: Electrode contacts tissue; water is driven out of cells - seals vessels

Blend Mode

• Combination of cut and coag waveforms in varying ratios

Types

• Monopolar: Active electrode (tip) + large indifferent/return electrode (diathermy pad on patient's thigh). Current passes through the patient's body. Greater burn risk.
• Bipolar: Current passes only between the two tips of forceps. No return electrode pad needed. Safer near neural tissue, in pediatric patients, in patients with pacemakers.

Precautions in Use

• Ensure good contact of diathermy pad (large surface area, well away from bony prominences)
• Keep cables away from metal instruments to avoid capacitive coupling
• Use minimal effective power setting
• Do not use in oxygen-enriched environments (fire hazard)
• Pacemaker precaution: Use bipolar whenever possible; have pacemaker programmer on standby; keep monopolar current path away from pacemaker
• Do not use on or near the penis (ring burns)
• Avoid use with alcohol-based skin preps until they dry
• Do not touch metal retractors with active electrode
• Use insulated instruments; inspect insulation before use

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E) LASER in Surgery

Basic Principle

• Electrons in a medium are excited to higher energy states by pumping (light, electricity, chemical)
• Stimulated emission produces photons of identical wavelength, phase, and direction (coherent, monochromatic, collimated)
• These photons are amplified in a resonant cavity with mirrors

Properties of Laser Relevant to Surgery

• Monochromatic: Single wavelength → selective absorption by specific tissue chromophores
• Coherent: All waves in phase → can be focused to tiny spot
• Collimated: Parallel beam → low divergence; precise delivery

Tissue Effects

• Photothermal: Coagulation (<100°C), vaporization (>100°C), carbonization (>300°C)
• Photomechanical: Shock wave tissue disruption (Q-switched lasers)
• Photochemical: Photodynamic therapy (PDT) - light activates photosensitizer drug

Types and Uses

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F) Surgical Suture Needles

Classification by Shape

• Straight needles: Skin sutures (using fingers, no needle holder needed); Keith needle (straight cutting) for musculoaponeurotic layers
• Curved needles: Most commonly used; require needle holder
  • 1/4 circle: Ophthalmology
  • 3/8 circle: Most common; general surgery, skin
  • 1/2 circle: Deep cavity sutures (bowel anastomosis, deep tissues)
  • 5/8 circle: Confined spaces (urology, deep pelvis)

Classification by Cross-Section (Tip)

• Round-bodied (tapered): Pushes tissue aside without cutting; for bowel, fascia, cardiovascular, general tissue - least tissue damage
• Cutting: Has 3 cutting edges; conventional cutting has apex on inside of curve; used for tough tissue (skin, fascia)
• Reverse cutting: Apex on outside of curve; stronger (less risk of suture cutting through); skin, fascia, orthopedics
• Blunt-tipped: For friable tissue (liver, kidney); reduces needlestick injury
• Trocar/Taper-cut: Combination of tapered body with cutting tip; for tough tissue like fascia/tendon

Other Features

• Swaged (atraumatic): Suture material attached to needle end; single-use; minimal tissue trauma through needle-suture junction
• Eyed needles: Reusable; suture threaded through eye; more traumatic
• Needle size: Measured by gauge and radius

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G) Hemostasis in Surgery

Intraoperative Methods of Controlling Bleeding

• Direct pressure / packing (gauze, laparotomy pads)
• Ligation (ties, transfixion sutures)
• Clip application (surgical clips, endoclips - hemostatic, titanium, polymer Hem-o-lok)
• Tourniquets, vascular clamps
• Balloon tamponade (endovascular balloons, intrauterine balloon)
• Sutures - over-sewing bleeding points
• REBOA (Resuscitative Endovascular Balloon Occlusion of Aorta)

• Monopolar and bipolar diathermy
• Argon Beam Coagulator (APC)
• LASER photocoagulation
• Ultrasonic energy devices (Harmonic scalpel - LigaSure): Coagulates vessels up to 7mm by ultrasonic vibration (55,000 Hz) causing protein denaturation; minimal thermal spread
• Advanced bipolar devices (LigaSure, EnSeal): Seal vessels up to 7mm reliably

• Vasoconstrictors: Epinephrine injection into mucosa/submucosa
• Antifibrinolytics: Tranexamic acid (IV/local), Aminocaproic acid
• Desmopressin (DDAVP): For von Willebrand/platelet dysfunction
• Systemic: FFP, platelets, cryoprecipitate, Factor VIIa (NovoSeven)

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H) Surgical Staplers in GI Surgery

Types of Staplers

Advantages

• Consistent anastomotic technique with reduced operator variability
• Faster than hand-sewn; reduced operative time
• Low anastomotic leak rates
• Enables anastomoses in difficult locations (deep pelvis - low colorectal)
• Laparoscopic procedures made feasible

Disadvantages

• Expensive (especially disposable)
• Cannot be tailored to specific tissue thickness without correct cartridge selection
• Mechanical failure possible
• Cannot be used in heavily irradiated/ischemic bowel without risk
• Requires adequate bowel mobilization for circular stapler placement
• Learning curve

Use for Bowel Anastomosis

• Small bowel: Functional end-to-end anastomosis using two fires of GIA stapler (side-to-side) + TA closure of enterotomy, or circular EEA
• Colorectal: Circular EEA via transanal approach; double-stapling technique for ultra-low anterior resection
• Esophageal: Circular EEA (ILS) for esophagogastrostomy or esophagojejunostomy

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SECTION 3: UROLOGY

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A) Lymphatic Drainage of the Testis

Primary Drainage

• Para-aortic (retroperitoneal) lymph nodes at L1-L2 level (alongside abdominal aorta and IVC)
• Right testis: Pre-aortic, inter-aortocaval, right paracaval nodes
• Left testis: Pre-aortic, left para-aortic (adjacent to left renal vessels at L2)

Secondary Drainage

• Iliac and inguinal nodes (only if tunica vaginalis/scrotum is involved, or after inguinal/scrotal surgery that alters lymphatics)

Clinical Significance

• Testicular cancer does NOT spread to inguinal nodes primarily
• Metastatic spread to inguinal nodes occurs only if scrotal skin is involved or prior hernia/orchidopexy has altered lymphatics
• Retroperitoneal lymph node dissection (RPLND) is the definitive staging/therapeutic procedure

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B) Retroperitoneal Lymph Node Dissection (RPLND)

Indications

1. Staging: Clinical stage I non-seminoma germ cell tumor (NSGCT) with high-risk features (lymphovascular invasion, embryonal carcinoma predominance)
2. Therapeutic: Post-chemotherapy RPLND for residual retroperitoneal mass in NSGCT (>1cm after BEP)
3. Salvage RPLND: Residual disease after first-line and second-line chemotherapy

"Salvage" RPLND

• Performed after failure of cisplatin-based chemotherapy
• Technically demanding due to retroperitoneal fibrosis and adhesions from prior chemo
• Addresses chemotherapy-resistant teratoma or viable cancer
• Requires complete resection of residual mass including adherent structures if necessary
• Morbidity higher than primary RPLND

Operative Technique

• Midline laparotomy (standard) or minimally invasive (laparoscopic/robotic)
• Boundaries of standard bilateral template RPLND:
  • Superior: Renal vessels
  • Inferior: Common iliac bifurcation
  • Lateral: Ureters bilaterally
  • Posterior: Aorta and IVC
• Nerve-sparing RPLND: Preserves sympathetic nerves (L1-L3 and hypogastric plexus) to prevent retrograde ejaculation
  • Right-sided primary tumor: Modified right template (spares left sympathetic chain)
  • Left-sided primary: Modified left template (spares right chain)

Complications

• Retrograde ejaculation (most common if nerve-sparing not done) - up to 70-100% without nerve-sparing vs <5% with nerve-sparing
• Lymphocele
• Ileus/bowel obstruction
• Vascular injury (aorta, IVC, renal vessels)
• Ureteral injury
• Chylous ascites (thoracic duct injury)
• Pulmonary complications (in post-BEP patients - bleomycin toxicity: avoid high FiO₂ intraoperatively)

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C) Hydrocele - Types and Management

Definition

Types

Primary vs. Secondary Hydrocele

Management

• Conservative: Observation in neonates (congenital type resolves in 80-90% by 18 months); aspiration (high recurrence, risk of infection - not standard)
• Surgical:
  • Jaboulay procedure: Eversion of tunica vaginalis sac around the testis (most common for large sacs)
  • Lord's plication: Multiple radial folds in tunica (for small/soft sacs); less dissection
  • Excision: For large thick-walled sacs - excise excess sac, leaving a collar of tissue posteriorly
  • In children: Via inguinal approach; ligation and division of patent processus vaginalis (herniotomy)
  • Secondary: Treat underlying cause (antibiotics for infection, orchidectomy for tumor)

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D) Undescended Testis (Cryptorchidism)

Definition

Classification

• Intra-abdominal: Testis within the abdomen; 20%
• Canalicular (inguinal canal): 70%; palpable; most common
• Ectopic: Descended through inguinal canal but sited abnormally (perineum, femoral triangle, root of penis, superficial inguinal pouch)
• Retractile: Can be brought into scrotum but returns; cremaster reflex; benign - resolves by puberty; no treatment needed

Consequences

1. Infertility: Bilateral cryptorchidism - 30-40% infertile; early orchidopexy (before 18 months) improves spermatogenesis
2. Malignant transformation: 4-10x increased risk of testicular cancer (particularly seminoma); EVEN after orchidopexy (but orchidopexy helps surveillance)
3. Testicular torsion: Increased risk due to inadequate anchoring
4. Inguinal hernia: Associated patent processus vaginalis in ~90%
5. Psychological impact: Absent testis in scrotum

Management

• HCG injection: May stimulate descent in bilateral cases in infants (limited success - ~25%)
• Orchidopexy (surgical correction): Standard treatment
  • Timing: Age 6-12 months (no later than 18 months) to maximize fertility outcomes
  • Technique: Inguinal approach, mobilize testis + spermatic cord, Dartos pouch fixation in scrotum
  • If impalpable testis: Laparoscopy to locate → laparoscopic orchidopexy (single or staged Fowler-Stephens)
• Orchidectomy: If atrophic or adult with cryptorchidism (high malignancy risk, no fertility benefit; insert prosthesis)

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E) Acute Scrotum

Differential Diagnosis

1. Testicular torsion (most important to exclude)
2. Torsion of testicular appendages (hydatid of Morgagni)
3. Acute epididymo-orchitis
4. Trauma - hematocele
5. Strangulated inguinal hernia (indirect)
6. Fournier's gangrene (necrotizing fasciitis - life-threatening emergency)
7. Henoch-Schonlein purpura (in children)
8. Idiopathic scrotal edema (children)
9. Insect bite, cellulitis

Torsion Testis - Clinical Features and Management

Clinical Features

• Age: Typically bimodal - neonates (extravaginal torsion) and puberty (12-18 years, intravaginal torsion)
• Sudden onset severe scrotal pain, often nocturnal
• May radiate to iliac fossa or lower abdomen (can mimic appendicitis)
• Nausea and vomiting common
• Swollen, erythematous, tender scrotum
• Cremasteric reflex absent (most important clinical sign)
• High-riding testis with horizontal lie ("bell clapper deformity")
• Prehn's sign: Pain NOT relieved by elevation (unlike epididymo-orchitis)
• DITTO / Angell sign: Contralateral testis often horizontal

Investigations

• Colour Doppler Ultrasound: Absent or reduced blood flow; confirms torsion - but do NOT delay surgery for imaging if clinically torsion
• Urine analysis (normal in torsion; pyuria in epididymo-orchitis)
• FBC, CRP

Management (for the 11-year-old with 2-hour history)

• SURGICAL EMERGENCY: Time to detorsion critical for testicular salvage
  • <6 hours: Near 100% salvage
  • 6-12 hours: 70-80% salvage
  • 12-24 hours: 20-50% salvage

  • 24 hours: <10% salvage

• Manual detorsion (rotate toward thigh, "opening a book") can be attempted while awaiting theater but do NOT delay surgery
• Scrotal exploration under GA: Bilateral approach (bell-clapper deformity is bilateral in 80%)
  • Detorse testis, wrap in warm saline swab, assess viability
  • Viable: Bilateral orchidopexy (3-point non-absorbable suture fixation - Dartos pouch)
  • Non-viable (black/infarcted after 10-15 min warm ischemia test): Orchidectomy + contralateral orchidopexy

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F) Testicular Tumours

Staging (TNM / IGCCCG)

• pT0: No tumor
• pT1s: Intratubular germ cell neoplasia (carcinoma in situ)
• pT1: Tumor limited to testis (including rete testis); no vascular/lymphatic invasion
• pT2: Tumor limited to testis with vascular/lymphatic invasion OR involvement of tunica albuginea/vaginalis
• pT3: Spermatic cord invasion
• pT4: Scrotal invasion

• N0: No lymph node involvement
• N1: ≤5 nodes, all ≤2 cm
• N2: 5+ nodes or any node 2-5 cm, or extranodal extension
• N3: Any node >5 cm

• M0: No distant metastasis
• M1a: Non-regional lymph nodes or lung metastases
• M1b: Other distant sites

• S0: Normal; S1: LDH <1.5 ULN; AFP <1000; hCG <5000; S2/S3: progressive elevation

Tumor Markers

• AFP (Alpha-fetoprotein): Elevated in non-seminoma (embryonal carcinoma, yolk sac); NOT elevated in pure seminoma
• β-hCG: Elevated in 60% seminomas (mildly), 100% choriocarcinoma; also embryonal/mixed
• LDH: Correlates with tumor bulk; prognostic marker
• PLAP (Placental Alkaline Phosphatase): Elevated in seminoma

Management of Suspected Right Testicular Tumour (25-year-old man)

• Clinical examination (check contralateral testis)
• Serum tumor markers: AFP, β-hCG, LDH (before any intervention)
• Ultrasound scrotum (gold standard - hypoechoic intratesticular mass)

• Inguinal orchidectomy (NOT trans-scrotal to avoid altering lymphatic drainage to inguinal nodes)
• Early ligation of spermatic cord at internal inguinal ring
• Send specimen for histopathology
• Sperm banking before any further treatment if fertility desired

• CT chest/abdomen/pelvis
• Repeat tumor markers (after orchidectomy - appropriate half-life decay: AFP T1/2 = 5 days, β-hCG T1/2 = 24-36 hours)
• If AFP not falling appropriately: residual/metastatic disease

• Stage I: Active surveillance (preferred); or adjuvant carboplatin (1-2 cycles); or para-aortic RT (20 Gy)
• Stage IIA/B: Radiotherapy; or BEP chemotherapy
• Stage IIC/III: BEP chemotherapy (3-4 cycles)

• Stage I: Surveillance (low-risk); or RPLND; or BEP ×1 (low-risk, LVI absent)
• Stage II: BEP chemotherapy ×3-4 cycles; +/- post-chemo RPLND for residual mass
• Stage III: BEP chemotherapy ×4 cycles (standard)

Classification of Seminoma

• Classic (typical) seminoma: Most common; age 30-40
• Spermatocytic seminoma: Older men (>50 years); benign behavior; no IGCCRG classification needed; treated by orchidectomy alone

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G) Male Infertility

Causes

• Hypogonadotropic hypogonadism (Kallmann syndrome, pituitary tumors)
• Hyperprolactinemia, thyroid disorders
• Exogenous androgens (steroid abuse suppresses FSH/LH)

• Cryptorchidism
• Varicocele (most common correctable cause - 40% of infertile men)
• Orchitis (mumps, TB)
• Gonadotoxins (chemotherapy, radiation, heat exposure)
• Genetic: Klinefelter syndrome (47,XXY), Y-chromosome microdeletions (AZFa, AZFb, AZFc)
• Idiopathic oligozoospermia/azoospermia

• Vasectomy (previous)
• Congenital bilateral absence of vas deferens (CBAVD) - associated with CF mutations
• Epididymal obstruction (post-infectious)
• Ejaculatory duct obstruction

Management

• Semen analysis (WHO 2021): Volume >1.4 mL; concentration ≥16×10⁶/mL; motility ≥42% total; morphology ≥4% normal (Kruger strict)
• Endocrine profile: FSH, LH, Testosterone, Prolactin
• Genetics: Karyotype, Y-microdeletion assay
• Varicocele: Grade I-III; surgical ligation (inguinal/subinguinal/laparoscopic) or radiological embolization
• Obstructive azoospermia: Microsurgical vasovasostomy, vaso-epididymostomy; or sperm retrieval (MESA, TESA, TESE) + ICSI
• Non-obstructive azoospermia: Micro-TESE + ICSI; donor sperm
• Hormonal: Gonadotropin therapy for hypogonadotropic hypogonadism
• ART: IUI, IVF, ICSI based on sperm parameters

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H) Vasectomy

Types

1. Conventional vasectomy: 1-2 small incisions in scrotum; vas deferens delivered, segment excised, ends ligated/cauterized/fascial interposition
2. No-scalpel vasectomy (NSV): Vas punctured with sharp curved hemostat through midline; less pain, fewer complications, faster healing - preferred technique
3. Percutaneous vasectomy: Needle-based technique; minimal incision

Complications

• Early: Hematoma (most common), wound infection, pain, bruising
• Late: Sperm granuloma (extravasated sperm → foreign body reaction), epididymal congestion/orchalgia, recanalization (vasectomy failure - rare <1%), anti-sperm antibodies, testicular pain syndrome
• Failure: Pregnancy rate 0.1-0.2% lifetime; higher in first 3 months (until azoospermia confirmed)

Criteria for Ideal Candidate

1. Has completed his family (or has no desire for biological children)
2. Fully informed about permanence; understands reversal success not guaranteed
3. Made decision independently (without coercion from partner)
4. Age ≥21 (some guidelines prefer >30 or has children)
5. Good general health; no bleeding disorders, active scrotal infection
6. Willing to use contraception until azoospermia confirmed (semen analysis at 8-16 weeks)

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SECTION 4: HEAD, NECK & MAXILLOFACIAL

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A) Cystic Hygroma

Embryology

• Cystic hygroma is a macrocystic lymphatic malformation
• Arises from failure of the embryonic lymphatic sac to connect with the venous system, or from sequestrated lymphatic tissue that fails to drain
• The jugular lymph sac (first lymphatic structure to appear, at 6 weeks gestation) fails to join the jugular vein
• 75% occur in the posterior triangle of the neck; also axilla, groin, mediastinum, retroperitoneum
• Associated with Turner syndrome (45,X) - large nuchal hygroma is a marker

Clinical Features

• Presents at birth or within first 2 years of life
• Soft, compressible, multilocular cystic mass in posterior triangle of neck
• May involve floor of mouth, tongue, face, mediastinum
• Brilliantly transilluminant (pathognomonic)
• Increases in size with crying/Valsalva
• Complications: Infection (becomes tender, firm), sudden expansion, respiratory obstruction (requires immediate aspiration/tracheostomy)

Management

• Sclerotherapy (first-line for macrocystic): OK-432 (Picibanil - streptococcal derivative), Bleomycin, Doxycycline, STS (sodium tetradecyl sulfate)
  • OK-432 most studied; complete/partial response in 60-90%
• Surgery: Complete surgical excision - gold standard but challenging due to involvement of vital structures
  • Indications: Failed sclerotherapy, airway compromise, infected/acutely enlarged, diagnosis uncertain
  • Risk: Facial nerve, accessory nerve, brachial plexus, great vessels in surgical field
  • Recurrence common if incomplete excision (multicystic nature)
• Combined approach: Sclerotherapy to shrink, then surgery for residual

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B) Branchial Cyst

Embryology

• Derived from 2nd branchial arch remnants (most common - 90%)
• Normally, the 2nd arch grows caudally to cover arches 3 and 4, with their ectodermal grooves forming a temporary sinus - the cervical sinus of His
• Failure of obliteration leaves a cyst (buried sinus)
• May also be from ectoderm inclusion in lymph nodes, or work of His (buried lymphoid epithelium)

• 1st cleft: Below/around ear/parotid
• 2nd cleft (most common): Anterior triangle, along anterior border of SCM
• 3rd cleft: Posterior triangle, near clavicle
• 4th cleft: Thyroid/parapharyngeal

Clinical Features

• Smooth, fluctuant, non-transilluminant cystic swelling along anterior border of SCM, at the junction of upper and middle thirds
• Usually present in 2nd-3rd decade (may enlarge after URTI due to lymphoid tissue in wall)
• Slight tethering to anterior border of SCM
• Contains turbid fluid (cholesterol crystals, lymphocytes on aspiration - pathognomonic)

Management of Branchial Cyst in 5-Year-Old Boy

1. Investigations: Ultrasound (first-line - confirms cystic nature, location, rule out vascular lesion), MRI for deep extension, FNAC if uncertain
2. Surgery: Complete excision under GA
   • Stepladder (staircase) incision if tract extends high up the neck
   • The cyst/sinus tract must be traced to the tonsillar fossa (2nd arch terminates there) and ligated
   • Trace between internal and external carotid arteries (2nd cleft passes between them)
   • Risk of injury to: CN XII (hypoglossal), accessory nerve, facial nerve, internal jugular vein

• Complete fistula with internal opening at tonsillar fossa and external opening on anterior neck
• Treatment: Complete excision via stepladder incision; cannulate with probe or inject methylene blue to identify the tract; trace to tonsil bed

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C) Lymph Node Levels of the Neck

Level Classification (Memorial Sloan Kettering/American Head & Neck Society)

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D) Types of Neck Dissection

Radical Neck Dissection (RND)

• Removes levels I-V + SCM + internal jugular vein + spinal accessory nerve (CN XI)
• Indicated for N2-N3 disease with involvement of these structures

Modified Radical Neck Dissection (MRND)

• Removes levels I-V; preserves one or more non-lymphatic structures
• Type I MRND: Preserve CN XI
• Type II MRND: Preserve CN XI + IJV
• Type III MRND (Functional neck dissection): Preserve CN XI + IJV + SCM - most common

Selective Neck Dissection (SND)

• Removes specific levels based on primary tumor site; preserves all non-lymphatic structures
• Supraomohyoid (SOHND): Levels I, II, III - for oral cavity cancer
• Lateral SND: Levels II, III, IV - oropharynx, hypopharynx, larynx
• Posterolateral SND: II, III, IV, V - cutaneous malignancies of scalp/posterior neck
• Central (anterior) SND: Level VI - thyroid cancer

Steps of Modified Radical Neck Dissection (Functional ND)

1. Patient supine, head turned away, sandbag under shoulders
2. Incisions: MacFee (two horizontal incisions), Schobinger (Y-shaped), or Conley
3. Raise skin flaps in subplatysmal plane
4. Identify and preserve CN XI (accessory nerve) - enters posterior triangle at Erb's point
5. Identify and preserve sternocleidomastoid muscle and IJV
6. Dissection of levels I-V from medial to lateral (or lateral to medial)
7. Identify and protect CN XII, cervical plexus, phrenic nerve, brachial plexus, common carotid artery, vagus nerve
8. Identify thoracic duct on left side (ligate if injured)
9. Submit specimen with level labeling
10. Closed suction drains; layered wound closure

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E) TNM Staging - Carcinoma of Oral Cavity

T (Primary Tumor)

• T1: ≤2 cm; Depth of Invasion (DOI) ≤5 mm
• T2: ≤2 cm with DOI 5-10 mm; OR 2-4 cm with DOI ≤10 mm
• T3: >4 cm; OR any size with DOI >10 mm
• T4a: Moderately advanced: invades adjacent structures (mandible cortex, maxillary sinus, skin of face); OR >4 cm + DOI >10 mm
• T4b: Very advanced: invades masticator space, pterygoid plates, skull base, encases ICA

N (Regional Lymph Nodes) - Based on 8th Edition AJCC

• N0: No regional nodes
• N1: Single ipsilateral ≤3 cm; ENE-
• N2a: Single ipsilateral 3-6 cm; ENE-
• N2b: Multiple ipsilateral ≤6 cm; ENE-
• N2c: Bilateral or contralateral ≤6 cm; ENE-
• N3a: Any node >6 cm; ENE-
• N3b: Any node with clinical ENE+ (extranodal extension)

M (Distant Metastasis)

• M0: None; M1: Present

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F) Premalignant Lesions of Oral Cavity

1. Leukoplakia: White patch that cannot be rubbed off and cannot be classified as any other condition; 5-15% malignant transformation
   • Homogeneous (flat, uniform) - lower risk
   • Non-homogeneous (speckled, verrucous, erythroleukoplakia) - higher risk (15-25%)
   • Management: Stop tobacco/alcohol; biopsy to exclude dysplasia; excision/ablation for high-grade dysplasia
2. Erythroplakia: Red velvety patch; highest malignant potential (40-50%); often represents carcinoma-in-situ
3. Oral Submucous Fibrosis: Areca nut (betel nut) chewing; progressive fibrosis; trismus; malignant transformation 8-10%
4. Actinic cheilitis: Lower lip; sun exposure; risk of SCC
5. Lichen planus (erosive type): Controversial; some classification as premalignant; ~1-2% risk
6. Chronic hyperplastic candidiasis (Candidal leukoplakia)
7. Sideropenic dysphagia (Paterson-Brown-Kelly/Plummer-Vinson syndrome): Iron deficiency anemia, dysphagia, koilonychia, post-cricoid web → post-cricoid carcinoma

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G) Carcinoma of Anterior 2/3 of Tongue

Etiopathology

• Most common site: Lateral border and ventral surface
• Risk factors: Tobacco, alcohol (synergistic), HPV 16 (oropharynx more than oral tongue), poor dental hygiene, chronic irritation (sharp teeth, ill-fitting dentures)
• Histology: SCC in 95%; rarely verrucous carcinoma, minor salivary gland tumors
• Molecular: p53 mutation, loss of 9p21 (p16/CDKN2A), EGFR overexpression
• Spreads: Local infiltration of tongue musculature, floor of mouth, mandible; lymphatics to levels I-III (skip metastases to level III common)

Diagnosis

• Symptoms: Ulcer on lateral tongue not healing >3 weeks; pain radiating to ear (CN V3, auriculotemporal nerve); dysphagia, dysarthria, altered speech in advanced disease
• Examination: Induration of ulcer edges; palpate deep infiltration; bimanual palpation; examine neck for nodes
• Investigations: Incisional biopsy (confirm histology); CT/MRI neck and tongue (depth of invasion, bone involvement, nodal staging); CT chest (distant mets); Orthopantomogram (OPG - mandible invasion); PET-CT for N0 neck to exclude occult nodes

Management

• Surgery: Primary treatment for resectable oral tongue cancers
  • T1/T2: Partial glossectomy (transoral or pull-through) + primary closure/flap
  • T3/T4: Hemiglossectomy or total glossectomy + reconstructive flap (RFFF - radial forearm free flap; anterolateral thigh flap for large defects)
  • Mandibulectomy (marginal or segmental) if bone invasion
• Neck: Elective SOHND (levels I-III) for N0 neck with DOI >4mm (occult nodal rate >20%); therapeutic MRND for N+
• Reconstruction: RFFF (thin, pliable, reliable - preferred for tongue); ALT flap; pedicled pectoralis major flap
• Adjuvant therapy: Post-op RT for T3/T4, positive margins, perineural invasion, LVI; Concurrent chemoradiotherapy for positive margins (involved) or ENE+
• Primary chemoradiation: For unresectable disease

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H) Carcinoma of Oral Cavity - Supra-Omohyoid Neck Dissection

Indications

• Elective (prophylactic) neck dissection in clinically N0 neck with primary oral cavity cancer where occult nodal risk is >15-20%
• DOI >4mm (current guideline - 8th edition AJCC)
• All T3-T4 oral cavity cancers regardless of N status
• After biopsy of nodes for staging

Extent of SOHND

• Removes levels I (Ia, Ib), II (IIa, IIb), and III
• Preserves: SCM, IJV, CN XI, CN XII, submandibular gland (unless directly involved)
• Lower boundary: Superior belly of omohyoid muscle

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I) Modified Radical Neck Dissection vs. N1 at Level 2 with Unknown Primary

Management of N1 at Level II with Unknown Primary (Carcinoma of Unknown Primary, CUP)

1. Full clinical examination including nasopharyngoscopy, indirect laryngoscopy
2. FNA/Core biopsy of node: Confirm malignancy; IHC including p16 (HPV), EBER (EBV), TTF-1, PSA, CK7/20
3. Imaging: CT/MRI neck + chest + abdomen; PET-CT (detects primary in ~25% of CUP)
4. Panendoscopy under GA: Direct laryngoscopy, esophagoscopy, bronchoscopy, nasopharyngoscopy with targeted biopsies of nasopharynx, tongue base, tonsil, pyriform sinus
5. Tonsillectomy (ipsilateral, or bilateral) - tonsil is primary site in 30-40% of HPV-related CUP
6. If primary found: Treat according to primary site
7. If no primary found: Selective neck dissection (levels I-IV) + irradiation to mucosa of oropharynx + neck

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J) Ludwig's Angina

Definition

Etiology

• 80-90% dental origin (lower molar infections - especially 2nd and 3rd molar periapical abscesses)
• Other: Trauma to floor of mouth, sublingual ranula, submandibular sialadenitis, post-op

Pathology

• Mixed flora: Streptococci, Staphylococci, anaerobes (Bacteroides, Fusobacterium)
• Spreads along fascial planes; rarely forms true abscess (unlike peritonsillar abscess)
• Can spread to parapharyngeal, retropharyngeal, mediastinal spaces (descending necrotizing mediastinitis - life-threatening)

Clinical Features

• Massive brawny edema of floor of mouth and neck ("bull neck" appearance)
• Tongue elevated and displaced posteriorly → airway obstruction
• Trismus, drooling, dysphagia, dysphonia, stridor
• Fever, toxemia

Management

• PRIORITY: SECURE AIRWAY
  • Awake fibreoptic intubation (preferred if able)
  • Tracheostomy under LA if airway severely compromised
  • Avoid general anesthesia until airway secured
• IV antibiotics: High-dose IV penicillin + metronidazole; or Co-amoxiclav; or Clindamycin in penicillin allergy; anti-staphylococcal cover
• Surgical drainage: Bilateral submandibular incisions + submental incision (visor incision); decompression of fascial spaces; drain placement
• Dental extraction of offending tooth
• ICU monitoring; watch for mediastinal extension (CT scan)

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K) Ranula and Plunging Ranula

Ranula

• A mucocele (retention cyst or extravasation cyst) arising from the sublingual gland or minor salivary glands of the floor of mouth
• Appears as a bluish, translucent, fluctuant cystic swelling lateral to lingual frenulum
• "Ranula" from Latin "rana" (frog) - resembles a frog's belly
• Transillumination: Positive

Plunging (Diving) Ranula

• Ranula that extends through or around the mylohyoid muscle into the submandibular/submental space or neck
• Presents as a neck swelling in addition to floor of mouth swelling (or as neck swelling alone)
• Large, soft, non-tender swelling below the jaw
• CT/MRI: Cystic lesion in floor of mouth + tail extending through mylohyoid

Management

• Simple ranula: Marsupialization (pack and excise roof of cyst, suture edges to floor of mouth mucosa) OR sublingual gland excision (definitive - prevents recurrence)
• Plunging ranula: Sublingual gland excision via intraoral approach (removes source) + aspiration/excision of cervical component via cervical approach if needed
• Recurrence after simple marsupialization alone is common (50-60%); sublingual gland excision reduces recurrence

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L) Salivary Gland Tumours

Classification

• Pleomorphic adenoma (mixed tumor): Most common (70% of parotid tumors); firm, slow-growing, mobile; risk of malignant transformation to carcinoma ex-pleomorphic adenoma if untreated long-term
• Warthin's tumor (Cystadenolymphoma): 2nd most common; bilateral in 10%; almost exclusively parotid; "hot" on Tc-99 scan
• Monomorphic adenoma (Basal cell adenoma), Oncocytoma

• Mucoepidermoid carcinoma: Most common malignant salivary tumor (overall); particularly common in parotid; graded low-high
• Adenoid cystic carcinoma: Most common in submandibular/minor glands; perineural invasion; slow growth but relentless recurrence; "cylindroma" pattern on histology
• Acinic cell carcinoma: Parotid; low grade
• Carcinoma ex-pleomorphic adenoma: Malignant transformation; rapid growth, pain, fixation from previously stable mass
• Polymorphous adenocarcinoma: Minor glands (palate)
• Squamous cell carcinoma, Lymphoma, Metastatic (skin SCC to parotid nodes)

Facial Nerve - Surgical Landmarks for Identification

1. Tragal pointer (pointer of tragus): The main trunk lies 1 cm deep and inferior to the tip of the tragal cartilage - most reliable landmark
2. Posterior belly of digastric muscle: Facial nerve crosses above the digastric as it emerges; dissect along digastric to find nerve
3. Tympanomastoid suture line: Nerve exits 6-8 mm deep to the inferior end of this suture
4. Stylomastoid foramen: Palpable as a notch; nerve immediately exits here
5. Mastoid process: Drop a line from mastoid; nerve is 1 cm anterior
6. Retrograde identification: Follow marginal mandibular branch from facial artery region backward

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M) Pharyngeal Pouch (Zenker's Diverticulum)

Presentation

• Usually elderly (>70 years); male predominance
• Progressive dysphagia (initially for solids, then liquids)
• Regurgitation of undigested food (hours after meals; no bile - above cricopharyngeus)
• Gurgling noise (borborygmi in neck)
• Halitosis
• Episodic pulmonary aspiration - recurrent chest infections, aspiration pneumonia
• Weight loss
• A visible soft neck swelling (usually left posterior triangle) that gurgles on compression (Boyce's sign)

Anatomy - Killian's Dehiscence

• Weak point between oblique fibers of inferior pharyngeal constrictor (thyropharyngeus) and transverse fibers of cricopharyngeus (upper esophageal sphincter)
• Pulsion diverticulum: Increased intra-pharyngeal pressure during swallowing due to cricopharyngeal dysfunction drives mucosa and submucosa through this area

Diagnosis

• Barium swallow (gold standard): Shows posterior diverticulum at pharyngoesophageal junction; do not scope a known pouch without awareness (risk of perforation)
• Endoscopy with extreme care; CT if malignancy suspected within pouch

Management

• Endoscopic stapler diverticulotomy (Dohlman/endoscopic): Most commonly used today; stapler divides the cricopharyngeal bar between pouch and esophagus; low morbidity; can be repeated
• Open surgery:
  • Cricopharyngeal myotomy alone (for small pouches <2 cm)
  • Pouch excision (diverticulectomy) + cricopharyngeal myotomy (for large pouches)
  • Pouch suspension (diverticulopexy) + myotomy (for large pouches in poor surgical risk)
  • Left cervical approach; left thyroid lobe retracted; identify pouch between carotid and trachea/esophagus

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N) Thoracic Duct Injury

Anatomy

• The thoracic duct arises from the cisterna chyli at L2 in the retroperitoneum, ascends through the chest (right of midline initially), crosses to the left at T4-T5, and drains into the left subclavian-jugular venous angle (Pirogoff angle)
• Drains lymph from entire body below diaphragm + left upper body + left head/neck

Causes of Injury

• Left radical neck dissection (most common surgical cause - at left subclavian-jugular angle)
• Left thoracic surgery (esophagectomy, lung resection, aortic surgery)
• Trauma (penetrating neck/chest injury)
• Central venous catheter placement

Clinical Presentation

• Chylous fistula/chylothorax: Milky discharge from wound or neck drain
• Fluid rich in triglycerides (>1.24 mmol/L), lymphocytes, fat globules staining with Sudan red
• Can lead to protein/immune deficiency, dehydration, electrolyte imbalance

Management of Chylous Fistula Following RND

• Low-fat diet with medium-chain triglyceride (MCT) supplements (MCT bypasses lymphatics, absorbed directly)
• Or total parenteral nutrition (TPN) to rest the lymphatics
• Pressure dressing over neck
• Somatostatin/Octreotide to reduce lymph flow
• 50% resolve within 2 weeks

• Surgical re-exploration and ligation of thoracic duct above clavicle
• Video-assisted thoracoscopic surgery (VATS) + pleurodesis for chylothorax
• Lymphangiography + embolization (interventional radiology)

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O) Thyroglossal Cyst and Fistula

Embryogenesis

• Thyroid gland descends from the foramen cecum (junction of anterior 2/3 and posterior 1/3 of tongue) through the tongue base, down the midline to its final position in front of the trachea
• The thyroglossal duct is the track of this descent; normally obliterates by 6-7 weeks gestation
• Failure of obliteration → thyroglossal duct cyst; infection + spontaneous rupture → thyroglossal fistula

Clinical Features

• Midline or paramedian cystic swelling in the neck
• Most common at or just below hyoid bone (subhyoid) - 50-60%
• Moves upward with swallowing AND with tongue protrusion (attached to foramen cecum via duct) - pathognomonic
• Soft, smooth, non-tender unless infected

Management of 4-Year-Old with Subhyoid Thyroglossal Cyst

1. Investigations: Ultrasound (confirm cystic, check for normal thyroid gland in situ), thyroid function tests (ensure normal thyroid)
2. Surgery: Sistrunk's operation (standard treatment)
   • Excision of the cyst
   • Excision of the central portion of the hyoid bone (to prevent recurrence - duct passes through/behind the hyoid)
   • Coring out a cylinder of tissue from hyoid to foramen cecum
   • Ligation and division of track at foramen cecum
   • Recurrence rate: <5% with Sistrunk; >30% with simple excision alone
3. If infected: Incise and drain first, allow inflammation to settle (6-8 weeks), then Sistrunk operation (operating in inflamed field increases risk of incomplete excision and recurrence)

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P) Tracheostomy

Indications

1. Acute upper airway obstruction not manageable by intubation (foreign body, trauma, Ludwig's angina, acute epiglottitis, severe burns to airway)
2. Failed intubation

1. Prolonged mechanical ventilation (>7-14 days) - reduces dead space, facilitates weaning, easier patient care, prevents laryngeal damage from prolonged intubation
2. After major head/neck surgery (bilateral neck dissection, laryngeal/pharyngeal resection)
3. Impaired laryngeal reflexes / risk of aspiration (bulbar palsy, neuromuscular disease)
4. Acute laryngeal pathology (bilateral vocal cord palsy)
5. Sleep apnea (rarely)

Complications of Tracheostomy

• Hemorrhage (intra-operative or from thyroid vessels)
• Subcutaneous emphysema, pneumomediastinum, pneumothorax
• False passage (tube into soft tissues)
• Apnea (loss of hypoxic drive in COPD)
• Laryngeal nerve injury
• Esophageal perforation

• Tube displacement/decannulation
• Tube blockage (crusting, mucus plug)
• Infection (peristomal)
• Swallowing difficulty

• Tracheomalacia: Cartilage weakening from cuff pressure; most important late complication
• Tracheal stenosis: Subglottic or at cuff site
• Tracheo-innominate artery fistula (life-threatening - pulsatile bleeding)
• Tracheo-oesophageal fistula: Posterior tracheal wall erosion
• Persistent stoma after decannulation
• Scarring, keloid formation

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Q) Cervical Lymphadenopathy

Classification

• Acute (<2 weeks): Infection
• Subacute (2-6 weeks): Infectious mononucleosis, cat scratch disease
• Chronic (>6 weeks): TB, lymphoma, carcinoma

1. Reactive (Inflammatory):
   • Bacterial: Streptococcal tonsillitis, dental sepsis, Staphylococcal skin infections
   • Viral: EBV (infectious mononucleosis), CMV, HIV, adenovirus
   • Specific: Toxoplasmosis, cat-scratch disease (Bartonella), tularemia
2. Granulomatous:
   • TB lymphadenitis (scrofula) - most common cause of chronic cervical lymphadenopathy in developing countries
   • Sarcoidosis
   • Histoplasmosis
3. Malignant:
   • Primary: Non-Hodgkin's and Hodgkin's lymphoma
   • Metastatic: From head & neck cancers (oral cavity, larynx, thyroid), distant primaries (lung, breast, stomach - left supraclavicular = Virchow's node / Troisier's sign)

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R) Tubercular Cervical Lymphadenitis

Etiopathogenesis

• Mycobacterium tuberculosis (pulmonary spread) or M. bovis (bovine - ingestion)
• Lymph nodes: Initially enlarged, firm, reactive → central caseation → coalescence → "collar-stud abscess" (pus tracking through deep fascia, subcutaneous = secondary abscess, connected by narrow neck)
• Stages (Rankin): Reactive lymphadenitis → periadenitis → central caseation → cold abscess formation → collar-stud abscess → skin involvement

Diagnosis

• FNAC: Most useful (90% sensitivity); shows caseating granulomas, epithelioid cells, Langhans giant cells, AFB (Ziehl-Neelsen stain)
• Mantoux test / IGRA (Quantiferon Gold): Positive
• CXR: May show pulmonary TB
• AFB culture (Lowenstein-Jensen medium): Gold standard for confirmation + sensitivity; slow (6-8 weeks)
• GeneXpert (PCR): Rapid, detects rifampicin resistance

Management

• ATT (Anti-Tubercular Therapy): First-line; 6-month regimen (2HRZE + 4HR)
  • Intensive phase (2 months): Isoniazid (H) + Rifampicin (R) + Pyrazinamide (Z) + Ethambutol (E)
  • Continuation phase (4 months): Isoniazid + Rifampicin
• Aspiration of fluctuant nodes if tense
• Surgery: For diagnostic excision if FNAC inconclusive, collar-stud abscess that has not resolved with ATT, sinus/skin ulceration, non-response to 4-6 weeks ATT, drug resistance

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S) Cleft Lip and Palate

Classification

• Unilateral (left > right) or bilateral
• Incomplete (partial) or complete (extends through nasal floor)
• Subcutaneous (forme fruste) - skin intact but muscle not fused

• Primary palate (anterior to incisive foramen): Cleft lip + alveolus
• Secondary palate (posterior to incisive foramen): Hard palate, soft palate, uvula
• Isolated palate cleft (Pierre Robin sequence: retrognathia + glossoptosis + cleft palate)
• Submucous cleft palate

Principles of Repair

• Timing: "Rule of 10" - 10 weeks, 10 pounds (4.5 kg), Hb ≥10 g/dL
• Millard rotation-advancement: Most widely used; rotates medial element, advances lateral element
• Tennison-Randall triangular flap: Uses Z-plasty principle; good for wide clefts
• Pre-operative nasoalveolar moulding (NAM) / lip taping: Reduces cleft width before repair
• Lip adhesion (preliminary procedure for very wide bilateral clefts)

• Timing: 6-18 months (optimize speech outcomes; earlier is better but palate growth still occurring)
• Von Langenbeck repair: Bilateral releasing incisions; bipedicled mucoperiosteal flaps; midline closure; leaves raw areas laterally
• Veau-Wardill-Kilner (VWK) pushback: Lengthens palate; good for anterior-posterior length but some growth disturbance
• Furlow double Z-plasty: Lengthens velum significantly; excellent speech outcomes; less growth disturbance; for isolated soft palate cleft
• Intravelar veloplasty: Reorientation of levator veli palatini muscle; crucial for velopharyngeal function

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T) Hydrocephalus

Classification

1. Obstructive (non-communicating): CSF flow obstructed within ventricles or at exits - Aqueduct of Sylvius stenosis (most common congenital cause), Dandy-Walker, posterior fossa tumor
2. Communicating: CSF absorbed poorly at arachnoid granulations; flow not obstructed - post-meningitis, post-subarachnoid hemorrhage, choroid plexus papilloma (overproduction)
3. Normal pressure hydrocephalus (NPH): Enlarged ventricles without raised ICP; triad: dementia + gait ataxia + urinary incontinence

• Congenital: Aqueductal stenosis (X-linked), myelomeningocele (Chiari II), Dandy-Walker
• Acquired: Tumor, hemorrhage, meningitis, trauma

Clinical Features

• Infants (before fontanelle closes): Enlarged head circumference, bulging anterior fontanelle, "setting-sun" sign (downgaze), papilledema, dilated scalp veins
• Children/Adults: Headache (worse in morning), vomiting, papilledema, visual changes (diplopia from 6th nerve palsy), cognitive decline, seizures

Diagnosis

• CT head: Enlarged ventricles (Evan's index >0.3), periventricular lucency (transependymal edema in acute)
• MRI: More detailed; shows cause; CSF flow studies (phase-contrast)
• LP manometry (communicating type)

Management

• CSF diversion: Ventriculoperitoneal (VP) shunt (most common), ventriculoatrial (VA) shunt
• Endoscopic Third Ventriculostomy (ETV): For obstructive hydrocephalus; creates floor of third ventricle communication - no implanted hardware
• Treat underlying cause: Remove tumor, treat meningitis
• Medical: Acetazolamide (temporary; reduces CSF production) - not definitive

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U) Extradural Hematoma

Clinical Features

• Usually follows temporal bone fracture (pterional blow) → ruptures middle meningeal artery (or vein/dural sinus)
• Classic triad: Head injury → brief loss of consciousness → lucid interval (minutes to hours) → rapid neurological deterioration (secondary LOC, headache, vomiting, seizures)
• Uncal herniation: Third nerve palsy (blown pupil - dilated, fixed, ipsilateral), contralateral hemiplegia, Cushing's reflex (hypertension + bradycardia)
• Lucid interval present in only ~30-50% (classic teaching) - many never regain consciousness

Investigations

• CT head (non-contrast): Biconvex (lenticular) hyperdense hematoma (does not cross sutures); associated skull fracture; midline shift
• Does not cross suture lines (dura tightly attached at sutures)

Management

• Immediate: ABC, secure airway, neurosurgical consultation
• Surgical: Craniotomy and evacuation of hematoma (emergency) + coagulation/clipping of middle meningeal artery
• Indications for surgery: >30 mL volume; thickness >15 mm; midline shift >5 mm; neurological deterioration
• Conservative: Small asymptomatic EDH (<1 cm, <30 mL, GCS 15, no shift) - close CT monitoring
• Post-op: ICP monitoring, mannitol, hyperventilation, VTE prophylaxis, seizure prophylaxis

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V) Carotid Body Tumour (Paraganglioma)

Clinical Features

• Painless, slow-growing mass at carotid bifurcation (anterior triangle, at level of hyoid)
• Fontaine's sign: Mass mobile horizontally but NOT vertically (tethered by carotid vessels)
• Transmitted pulsation; may have thrill/bruit
• Lyre sign on angiography: Widening (splaying) of internal and external carotid arteries around the tumor
• May be secreting (rarely functional): Hypertension, palpitations, sweating (secrete catecholamines)
• 10% bilateral; 10% malignant; associated with SDH gene mutations (Shamblin III being most adherent to vessels)
• Familial in 30%; screening of first-degree relatives recommended

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COMPLETE ANSWER KEY - SURGICAL ONCOLOGY, SURGICAL INSTRUMENTS, UROLOGY & HEAD/NECK SURGERY

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