Extragastrointestinal stromal tumor of the urinary bladder: a case report.

Received October 2009 Accepted November 2009 INTRODUCTION A gastrointestinal stromal tumor (GIST) is primarily located in the gastrointestinal tract. It is classified as a mesenchymal tumor that shows a CD117 (c-KIT)-positive mesenchymal spindle or epithelioid neoplasm. Tumors outside the gastrointestinal tract that were histologically similar to GISTs and showed immunopositivity for CD117 were classified as extragastrointestinal stromal tumors. Although there were several reports of tumors outside the gastrointestinal tract, only a case of extragastrointestinal stromal tumor in the urinary bladder was reported.(1,2) Herein, we report another case arising in the urinary bladder presenting with submucosal polypoid mass.