Neural Fibrolipoma : Microscopic Features

Neural fibrolipoma is a localized, benign, tumorlike expansion of fibrofatty tissue around major nerves and their branches. It is known by a variety of names. Median nerve is most commonly affected. It presents as a slow growing, soft mass involving the volar aspect of the hand, wrist, and forearm. Most cases present within the first three decades of life. Many are present at birth or during infancy. Patients present with compression neuropathy and develop pain, tenderness, and sensorimotor deficits. One-third have bone overgrowth and macrodactyly of the digits supplied by the affected nerve. Microscopically, there is overgrowth of epineurial fibrofatty tissue with infiltration of the nerve trunk. Perineurium shows concentric thickening with pseudo-onion bulb-like change. Some cases show osseous metaplasia. There is no effective cure. Complete resection is contraindicated as it causes sensorimotor deficits. Pain relief can be obtained by nerve decompression.