A Case of Collision Tumor with Leiomyoblastoma and Gastric Cancer

There have been few reports of patients with leiomyoblastoma of the stomach in association with other malignancies of the alimentary tract. Moreover, a collision tumor with a leiomyoblastoma and cancer in the stomach is very rare. An 80-year-old man presented with a expirational dyspnea and hematemesis. Blood laboratory examinations showed severe anemia and malnutrition. Upper gastrointestinal radiography and an endoscopic examination revealed a submucosal tumor on the gross curvature of the gastric body and Borrmann type4 gastric cancer in the antrum. Tissue from an endoscopic biopsy histologically revealed a poorly differentiated adenocarcinoma. A diagnosis of a Borrmann type4 gastric cancer with a submucosal tumor of the stomach was subsequently confirmed. A subtotal gastrectomy was performed, and the histological findings of the Borrmann type4 gastric tumor revealed a pooly differentiated adenocarcinoma and a submu cosal tumor leiomyoblastoma of clear cell type. In addition, the gastric tumor was located close to the capsule of the leiomyoblastoma but did not invade it. There was no admixture of the two cellular components, indicating that the tumors were of the collision type. The rarity of the collision phenomenon involving a gastric cancer and a leiomyoblastoma is apparent since there in only one documented case reported in the literature.