A giant plexiform schwannoma of the brachial plexus: case report^[*]

Abstract

We report the case of a patient who noticed muscle weakness in his left arm 5 years earlier. On examination, a biloculate mass was observed in the left supraclavicular area, and Tinel’s sign caused paresthesia in his left arm. Magnetic resonance imaging showed a continuous, multinodular, plexiform tumor from the left C5 to C7 nerve root along the course of the brachial plexus to the left brachia. Tumor excision was attempted. The median and musculocutaneous nerves were extremely enlarged by the tumor, which was approximately 40 cm in length, and showed no response to electric stimulation. We resected a part of the musculocutaneous nerve for biopsy and performed latissimus dorsi muscle transposition in order to repair elbow flexion. Morphologically, the tumor consisted of typical Antoni A areas, and immunohistochemistry revealed a Schwann cell origin of the tumor cells moreover, there was no sign of axon differentiation in the tumor. Therefore, the final diagnosis of plexiform Schwannoma was confirmed.

Keywords

brachial plexus - giant - plexiform schwannoma

^*This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

• References

• 1 Harkin JC, Arrington JH, Reed RJ. Benign plexiform schwannoma: a lesion distinct from plexiform neurofibroma. J Neuropathol Exp Neurol 1978; 37: 622
• 2 Enzinger FM, Weiss SW. Benign tumors of peripheral nerves. In: Enzinger FM, Weiss SW. Mosby; St. Louis: 4th edition 2001: 1111-1207
• 3 Baser ME, Friedman JM, Evans GR. Increasing the specificity of diagnostic criteria for schwannomatosis. Neurology 2006; 66: 730-732 10.1212/01.wnl.0000201190.89751.41 16534111
• 4 Woodruff JM, Marshall ML, Godwin TA, Funkhouser JW, Thompson NJ, Erlandson RA. Plexiform (multinodular) schwannoma, A tumor simulating the plexiform neurofibroma. Am J Surg Pathol 1983; 7 (7) 691-697 10.1097/00000478-198310000-00009 6638259
• 5 Rosalie EF, Michael JO. Neurofibroma and schwannoma. Current Opinion in Neurology 2002; 15: 679-684 10.1097/00019052-200212000-00004 12447105
• 6 Agram NP, Prakash S, Antonescu CR. Deep-Seated Plexiform Schwannoma, A Pathologic Study of 16 Cases and Comparative Analysis With the Superficial Variety. Am J Surg Pathol 2005; 29: 1042-1048 16006798
• 7 Ishida T, Kuroda M, Motoi T, Oka T, Imamura T, Machinami R. Phenotypic diversity of neurofibromatosis 2; Association with plexiform schwannoma. Histopathology 1998; 32: 633-640
• 8 Shinde SV, Tyagi DK, Sawant HV, Puranik GV. Plexiform schwannoma in schwannomatosis. J Postgrad Med 2009; 55: 206-207 10.4103/0022-3859.57406 19884750
• 9 Woodruff JM, Selig AM, Crowley K, Allen PW. Schwannoma (neurilemoma) with malignant transformation; a rare distinctive peripheral nerve tumor. AM J Surg Pathol 1994; 18: 882-95 10.1097/00000478-199409000-00003 8067509