Largest pediatric scrotal lipoma with perineal extension: a rare case expanding the anatomic spectrum and diagnostic...

Scrotal lipomas are exceptionally rare in children, with only a few cases reported worldwide and most measuring less than 7 cm. Giant pediatric scrotal lipomas with multi-compartmental perineal extension have not been previously described. This case presents the largest documented pediatric scrotal lipoma, with an analytic framework for understanding diagnostic pitfalls and rare visual documentation of surgical anatomy.

A 5-year-old boy presented with six months of progressive left scrotal swelling clinically consistent with a large hydrocele. Ultrasound suggested heterogeneous fatty tissue, while MRI performed elsewhere was interpreted as omental herniation. Standard inguinal exploration for presumed hydrocele revealed a normal testis without a hernia or fluid collection, prompting intraoperative diagnostic reassessment. Subsequent scrotal exploration identified a well-encapsulated lipoma measuring 14 × 12 × 7 cm, located between the dartos and scrotal skin with deep extensions to the pubic arch, penile root, and pelvic floor. Complete excision was achieved while preserving all neurovascular structures. Histopathology confirmed mature lipoma. At one-year follow-up, the patient remained asymptomatic with symmetric testes and no recurrence.

This case demonstrates how ultra-rare pediatric conditions can closely mimic common scrotal diseases, leading to diagnostic anchoring despite supportive imaging. It documents, to the best of our knowledge, the largest pediatric scrotal lipoma to date and the only case with extensive perineal extension. Intraoperative diagnostic flexibility, combined with meticulous anatomical dissection, enables safe and complete excision with excellent functional outcomes.