Hibernoma of the thigh: a lipoma-like variant rare tumour mimicking soft tissue sarcoma.

A 43-year-old Caucasian woman appeared with painless progressively enlarging tumour of the anterior part of the left thigh of approximately 6 months' duration. A differential imaging diagnosis of liposarcoma or large lipoma was made. An excisional biopsy was performed with complete removal of a large lobulated and encapsulated grossly ovoid mass. Frozen section diagnosis was unidentified lipomatous tumour with no evidence of malignancy. The final pathological diagnosis was lipoma-like hibernoma. The patient's postoperative course was uneventful and discharged on the seventh postoperative day with full function of the involved leg. Hibernoma is benign tumour and it is not known to recur after complete local excision which is the treatment of choice.