The roentgen findings in gastric leiomyomas and leiomyosarcomas.

Abstract

Among benign tumors of the stomach leiomyoma ranks second in incidence, being exceeded only by adenomatous polyps. Meissner (22) discovered 23 leiomyomas in a careful study of 50 stomachs chosen at random at autopsy. In three series of benign gastric tumors, the incidence has been reported as 36.6 per cent, 39.9 per cent, and 60 per cent, respectively (2, 3, 8). In a series of 711 gastric resections (28), leiomyomas made up 0.43 per cent of the cases. Rieniets (29) reported the incidence of gastric leiomyomas to be 16 per cent, and of gastric leiomyosarcomas 6 per cent, in 200 consecutive autopsies. Leiomyosarcomas are said to form about 10 per cent of all gastric sarcomas (31). Of 30 smooth-muscle tumors of the stomach, Golden and Stout (11) found 65 per cent to be benign and 35 per cent malignant. Accurate differentiation between leiomyoma and leiomyosarcoma by clinical observation, roentgenography, gastroscopy, or direct visualization at surgery, without histologic examination, is not always possible. Melnick (23) reported a case of histologically benign leiomyoma of the stomach with liver metastases, which suggests that even microscopic differentiation is difficult. Nine proved cases, 2 leiomyomas and 7 leiomyosarcomas, form the basis of the present study. Clinical Features No characteristic age or sex predilection of gastric leiomyomas and leiomyosarcomas has been observed. Our cases were all in men, with an age range from thirty-eight to seventy-six. The patient may be asymptomatic. Hemorrhage in the form of hematemesis or melena is a common sign, and symptoms of anemia, such as weakness, fatigue, malaise, headache, or dizziness, are often observed. Pseudo-ulcer symptoms, as epigastric pain, burning, nausea, vomiting, or anorexia, are next in order of frequency. Weight loss usually is not more than 15 pounds. Gastric acidity findings are not constant. In a few cases, a mass is palpable. Rarely, symptoms and signs of peritonitis may occur secondary to perforation of the tumor into the peritoneal cavity. Liver metastases and, infrequently, pulmonary or peritoneal metastases are found in conjunction with leiomyosarcomas. Pathology Gastric leiomyomas and leiomyosarcomas are extramucosal tumors which arise from the smooth muscle in the stomach wall. The former are composed microscopically of interlacing, irregularly arranged smooth-muscle fiber bands, usually with evidence of adult differentiation (Fig. 4C). In leiomyosarcomas, anaplastic cells with multiple mitoses, hyperchromatism, and a tendency toward round or ovoid nuclei, rather than those of spindle shape, are observed. Degenerative changes overlying mucosal ulcerations are common. Calcification may occur and in rare instances is visualized roentgenographically as a calcified tumor (14).