Intranodal Schwannoma Mimicking a Gastrointestinal Stromal Tumor of the Stomach: A Case Report

A 66-year-old-woman is presented with intranodal schwannoma of the retroperitoneum. Ultrasonography (US) and computed tomography (CT) results demonstrated a large encapsulated mass with internal cystic or necrotic portions in the gastrosplenic space. The tumor abutted the greater curvature of the gastric body and slightly indented the proximal small bowel loops on a small bowel series. The observations suggested a gastrointestinal stromal tumor. The mass was surgically proven to be a retroperitoneal tumor and histopathologically intranodal ancient schwannoma.