A giant multi-compartment lipoma of the hand causing median nerve compression: A case report and review of literature.

INTRODUCTION & IMPORTANCE: Lipomas are slow growing benign soft tissue tumors that arise from mesenchymal preadipocytes. Histologically they are composed of mature adipocytes. They typically have a shawl like distribution in the body, anywhere from the subcutaneous space to bone, but are seen only rarely in the hand. When >5 cm, they are referred to as 'giant lipoma' and can be symptomatic due to neurovascular compression and impaired hand function.

CASE PRESENTATION: A 51-year-old forensic analyst presented with a progressively enlarging lump over the thenar eminence and palm of his dominant right hand for 2 years duration. Although initially asymptomatic, he developed progressive numbness over the radial 21/2 fingers and impaired hand function due to its size resulting in occupational impairment. Examination revealed a 5x5cm painless lobulated lump over palm. NCS showed evidence of median nerve compression. MR imaging revealed a giant lipoma involving the thenar and midpalmar space. Enbloc surgical excision was performed and histology was confirmatory.

CLINICAL DISCUSSION: Lipomas of the hand could be superficial or deep space. They are slow growing and asymptomatic initially and are brought to attention due to cosmetic concerns, nerve compression or mechanical hand impairment with enlargement. Giant lipomas must be treated with suspicion due to denovo liposarcoma and risk of sarcomatous change.

CONCLUSION: Giant multi-compartment lipomas of the hand are rare. Surgical excision is advocated for suspicion of malignancy, nerve compression and functional limitation. Enbloc resection without fragmentation has minimal risk of recurrence and complications.