Gastric stromal tumor of the uncommitted type treated by repeated removal of recurrent tumors: case report with immunohistochemical and ultrastructural observations

Abstract

A gastric stromal tumor was found in a 61-year-old man. The patient was treated by total gastrectomy, but the tumor recurred, 26 months after surgery, in the peritoneal cavity at the anastomotic site of the esophagojejunostomy, with metastases to mesenteric lymph nodes. This second tumor was removed surgically, but, 7 years after the gastrectomy, multiple recurrent tumors were found in the peritoneal cavity; once again the tumors were removed. Although the recurrent tumors were surgically removed twice, the patient died of the disease 8 years after the initial surgery. Histologically, the gastric tumor consisted of spindle-shaped neoplastic cells arranged in interlacing tumor bundles with frequent mitotic figures (four mitoses per ten high-power fields). Although the recurrent tumors also consisted of spindle-shaped neoplastic cells, myxoid changes were prominent. Immunohistochemically, the neoplastic cells gave diffuse positive reactions only with antibodies CD34 and vimentin among a variety of antibodies tested. Ultrastructural analysis failed to provide conclusive evidence for the neural or muscular origin of the tumor. The gastric tumor was therefore considered to be gastric stromal tumor of uncommitted type with malignant behavior. The patient survived for a long-term period after the gastrectomy, followed repeated removal of the recurrent tumors.