Lipoma of the finger with bone erosion.

Lipoma of the finger is rare, and there have been few case reports of lipoma causing bone erosion in the finger. We report on a patient with a long-standing lipoma that caused deep erosion of the distal phalanx of the index finger. A 38-year-old man presented with a painful mass of the left index finger. Anteroposterior radiographic images showed a radiolucent area in slightly distal to the center of the distal phalanx. Magnetic resonance imaging revealed a large soft-tissue mass with high signal intensities and slight irregularity on both T1- and T2-weighted images which suggested lipoma. The patient underwent marginal excision of this tumor and curettage of the bone surface of the erosion. The pain resolved after surgery. The diagnosis of lipoma was confirmed with postoperative histological examination. Lipoma should be included in the differential diagnoses of a finger tumor, even if radiography shows bone erosion.