Spindle cell lipoma of the floor of mouth.

The patient was a man in his 60s with the gradually increasing mass in his mouth. A well-defined, elastic soft mass with a major diameter of 60 mm was found on the right floor of mouth. The magnetic resonance imaging findings showed a well-defined mass with high signal on both T1 and T2-weighted image in the right sublingual space. The mass was slightly heterogeneous inside and had a septum-like appearance. The tumor was resected with care not to damage the capsule. Histopathological findings showed mature adipocytes, spindle-shaped cells, and collagenous components. Spindle cells were CD34-positive. The tumor was diagnosed as spindle cell lipoma. The patient was followed up for 6 months with no recurrence. Spindle cell lipoma is a rare entity and this is the largest case in the oral cavity. Because there are wide variety of adipocytic tumors, the careful examination of their imaging and histopathological findings is essential.