67 year-old woman who presented with fever, abdominal discomfort, an abdominal mass, and blood in the stool. Upper endoscopy revealed a poorly distensible stomach. Gastric walls were thickened and firm, with scattered focal ulceration (LEFT). There was a large, deep ulcer (CENTER) which led to a large cavity filled with fluid and necotric debris (RIGHT). This proved to be a leiomyosarcoma measuring 18 cm, with central necrosis, communicating with the gastric lumen.