Congenital melanocytic nevus with features of hybrid schwannoma/perineurioma
Article first published online: 11 MAR 2013
Copyright © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd
Journal of Cutaneous Pathology
Volume 40, Issue 5, pages 497–502, May 2013
How to Cite
Congenital melanocytic nevus with features of hybrid schwannoma/perineurioma., , .
- Issue published online: 11 APR 2013
- Article first published online: 11 MAR 2013
- Manuscript Accepted: 16 DEC 2012
- Manuscript Revised: 12 DEC 2012
- Manuscript Received: 7 AUG 2012
- hybrid schwannoma/perineurioma;
- melanocytic nevus;
Neural differentiation by melanocytic nevi represents a well-recognized phenomenon, and melanocytic nevi with perineurial differentiation have been reported recently. We reported a case of a congenital melanocytic nevus with histopathologic features of hybrid schwannoma/perineurioma. The patient was a 36-year-old male who presented with a black tumor on his arm since birth. Histopathology showed a congenital melanocytic nevus in the superficial dermis, but more strikingly, in continuity with the melanocytic nevus, there was a well-circumscribed but unencapsulated nodule in the deep dermis. The nodule was composed of cellular and myxoid areas with storiform, laminated or whorled growth patterns. The cellular area was mainly composed of proliferation of plump spindle, oval or epithelioid cells. The myxoid area was mainly composed of proliferation of slender spindle cells with mucin deposition. Immunohistochemical stains showed that the cellular area was positive for S100 and CD34, weakly positive for EMA, negative for Glut-1 and collagen IV, the myxoid area was positive for S100, negative for CD34, strongly positive for EMA and focally positive for Glut-1 and collagen IV. Our results show that congenital melanocytic nevi may show neural differentiation with histopathologic features of hybrid schwannoma/perineurioma.