Schwannomas of Gastrointestinal Tract; a comprehensive review

Abstract

Gastrointestinal Schwannomas (GIS) are neurogenic, spindle cell, mesenchymal tumors, and arise from Schwann cells of myenteric plexus; the cells which form the sheath of the nerves. Schwannomas (SNs) usually arise from spinal roots and peripheral nerves in Schwannomatosis, the third major form of neurofibromatosis, but they are most wellknown to originate from cranial nerves as in vestibular schwannomas. On the contrary, a sporadic Schwannoma which occurs in hollow organs such as the GI tract is remarkably rare. The Gastrointestinal Schwannomas pose a diagnostic & interventional challenge as it is difficult to differentiate them, peri-operatively or pre-operatively, from more commonly occurring, more malignant, Gastrointestinal-Stromal Tumors (GIST). The exact incidence of gastrointestinal Schwannomas is not known, due to lack of consensus in the nomenclature of these tumors; they are called