A multi-panel medical figure documenting a case of a scrotal epidermoid cyst in a pediatric patient. (a) A clinical photograph shows a prominent, smooth, midline scrotal mass (white arrow). (b1, b2) T2-weighted axial and coronal MRI scans reveal a tubular, high-signal cystic lesion (white arrows) extending from the scrotum toward the pelvic floor, demonstrating penetration of the penile corpora cavernosa (black arrows). (c) Intraoperative photograph highlights the elongated, reddish-tan tumor (white arrows) being dissected as it traverses the corporal tissue (black arrows). (d) Gross specimen image shows the excised tumor components, including a larger peripheral segment and a smaller central segment, with a 10 mm scale bar for reference. (e) A histopathological micrograph (H&E stain, 100x) displays a cyst wall lined by mature stratified squamous epithelium with focal lymphocytic infiltration, confirming the diagnosis of a benign epidermoid cyst. This case illustrates the rare clinical presentation of an epidermoid cyst penetrating deep into penile erectile structures, requiring precise surgical management to preserve functional anatomy.

Multi-modal imaging and histopathology of an atypical Testicular Epidermoid Cyst (TEC) in a 26-year-old male. (A) Scrotal ultrasonography displays a large, heterogeneous intratesticular mass with a central focus of hyperechogenicity and significant posterior acoustic shadowing (yellow arrow), suggesting calcification. (B-E) Multi-sequence MRI of the scrotum shows a well-defined mass. A mural nodule (yellow circle) appears hyperintense on T1-weighted imaging (B) and hypointense on T2-weighted (C) and SPAIR (D) sequences. Post-contrast THRIVE sequence (E) demonstrates gadolinium enhancement of the nodule, indicating vascularity. (F) Histopathology (H&E, 20x) reveals a cyst wall with keratinized epithelium and a disorderly internal accumulation of keratin (black arrow), lacking the classic 'onion-skin' arrangement. (G-J) Focused MRI sequences highlight a 'small black ring sign' on T2-weighted and SPAIR images (yellow arrows), which remains non-enhanced on post-contrast THRIVE imaging (J), consistent with a calcified component. This case demonstrates atypical radiological features of TEC, including the absence of alternating concentric rings and the presence of a vascularized mural nodule.

This clinical photograph displays a gross examination of the male genital region featuring a significant midline scrotal swelling. The image identifies a 'MIDLINE CYST' situated centrally within the scrotum, positioned between the 'RIGHT TESTIS' and 'LEFT TESTIS'. The cyst is spherical, prominently larger than the individual testicles, and causes visible stretching of the overlying scrotal skin, resulting in a smoother surface texture compared to the adjacent wrinkled and rugose scrotal folds. The lesion appears discrete and non-inflammatory, with no signs of erythema or ulceration. This visual demonstrates a typical presentation of a large scrotal midline cyst, which in a clinical context could represent an epidermoid cyst or a median raphe cyst. The educational focus is on the anatomical localization of scrotal masses and the differentiation between intratesticular and extratesticular pathology through physical inspection and labeling.