Patient Summary

PET-CT Findings (Key Points)

Diagnosis

FIGO Staging (2018 system):

• Cervical tumor extending into the upper vagina = at minimum Stage II
• Parametrial involvement - not explicitly stated; the tumor is large (>4 cm) and abutting rectum/bladder without clear infiltration
• Pelvic lymph node metastasis (left external iliac) = under FIGO 2018, pelvic LN positivity upstages to Stage IIIC1

Most likely stage: FIGO Stage IIIC1r (pelvic lymph node metastasis confirmed on imaging - 'r' suffix denotes radiological staging)

Note: The FIGO 2018 staging system - which is incorporated into this report - uses imaging and pathologic measurements to determine pelvic/para-aortic nodal involvement. The left external iliac node (SUVmax 14.3) strongly indicates metastatic disease, placing this patient in Stage IIIC1.

Treatment Plan

1. Primary Treatment: Concurrent Chemoradiotherapy (CCRT)

Radiotherapy

• External Beam Radiation Therapy (EBRT): 45-50 Gy to the pelvis in 25-28 fractions
  • Field should cover the primary tumor, parametria, upper vagina, and pelvic lymph nodes (including the left external iliac node)
  • Extended-field RT to para-aortic nodes may be considered if para-aortic nodes are suspicious (they are not significantly enlarged here, but close monitoring is warranted)
• Brachytherapy (intracavitary/interstitial): Given after EBRT - this is an essential component. Total EQD2 to point A: typically ≥85 Gy. Omission of brachytherapy significantly worsens outcomes.

Concurrent Chemotherapy (Radiosensitizer)

• Cisplatin 40 mg/m² IV weekly (max 70 mg/week) x 5-6 cycles - preferred agent
• Alternative if cisplatin-intolerant: Carboplatin (AUC 2 weekly)

2. Additional Systemic Therapy (Consider)

• Pembrolizumab 200 mg every 3 weeks x 5 cycles concurrent with CCRT, then 400 mg every 6 weeks maintenance x 15 cycles

3. Pre-treatment Work-Up Required

• Histopathology/biopsy confirmation (squamous cell carcinoma vs adenocarcinoma vs other - guides PD-L1 testing)
• MRI pelvis (preferred for local staging and treatment planning - better soft tissue delineation than PET-CT alone; Grainger & Allison's Diagnostic Radiology)
• PD-L1 testing (CPS score) if pembrolizumab is being considered
• Renal function tests (creatinine, GFR) before cisplatin - note serum creatinine is 0.70 mg/dL (normal here)
• Complete blood count, LFTs (fatty liver noted - monitor hepatotoxicity)
• USG abdomen - for gallbladder/biliary system evaluation (liver is enlarged with fatty changes)
• Fertility counseling - patient is 48 years, likely perimenopausal; ovarian function/hormone status discussion
• Consider para-aortic lymph node dissection/biopsy for pathological staging if upstaging would change field borders

4. Response Assessment

• PET-CT reassessment 3 months after completion of CCRT
• If complete metabolic response: surveillance
• If residual disease: assess for salvage (exenteration in selected cases; additional systemic therapy)

Summary Table

Disclaimer: This analysis is based on imaging findings only. Final clinical staging, treatment decisions, and all therapeutic interventions must be made by the treating oncologist/gynecologic oncologist in conjunction with a multidisciplinary tumor board, following clinical examination, histopathological confirmation, and institutional protocols.