Retroperitoneal Hibernoma Presenting as a Gastrointestinal Surgical Diagnostic Challenge: A Rare Benign Lipomatous Tumor and Literature Review

Background

Hibernoma is an uncommon benign adipocytic neoplasm showing differentiation toward brown fat. Although it usually occurs in anatomical sites where residual brown adipose tissue persists, retroperitoneal involvement is particularly uncommon, with fewer than 60 cases reported.