The histogenesis of nerve sheath myxoma: report of a case with electron microscopy.

The case is described of a 71-yr-old female with a tumour in the pulp of the left index finger. The histology was that of a myxoma of nerve sheath or Pacinian neurofibroma. Electron microscopy of the tumour provides convincing evidence for an origin from the perineural cells. The location of these tumours, suggestive histology and perineural origin provides support for the belief that they arise from sensory nerve endings.