Daniel Rosok, Hubertus Hautzel, Stefanie Bertram, Lale Umutlu, Luca Salhöfer
Hibernomas are rare benign tumors derived from brown adipose tissue that may mimic malignancy on imaging. We report a 21-year-old woman with multiple endocrine neoplasia type 1 (MEN1) undergoing serial somatostatin receptor (SSTR) PET imaging after curative treatment for a pancreatic neoplasia in complete remission. An intramuscular lesion showed moderate SSTR expression and slow progressive growth. MRI demonstrated heterogeneous enhancement and diffusion restriction, raising concern for malignancy. Histopathology after biopsy confirmed hibernoma. This case highlights hibernoma as a potential pitfall in SSTR-targeted PET imaging, particularly in MEN1, and underscores the importance of multimodality imaging and histopathologic correlation for accurate diagnosis.