Primary tumors of the esophagus other than squamous cell carcinoma--histologic classification and statistics in the surgical and autopsied materials in Japan.

Clinicopathological features of 405 patients with esophageal tumors other than squamous cell carcinoma, which were resected surgically at 68 institutions in Japan, were analyzed and compared with those of 4,995 cases of esophageal malignant neoplasms autopsied during 19 years (1958-1976) in Japan. Of 405 surgical cases, 149 were benign tumors, most of which (89%) were leiomyomas. The incidence of malignant tumors other than squamous cell carcinoma was 2.1% in the surgical, and 7.2% in the autopsied cases of esophageal cancer. Malignancies were classified into 15 histologic types. Most of them did not differ in sex and age incidence or location of the primary site from squamous cell carcinoma, except for adenocarcinomas, in which there was a greater incidence of occurrence in the lower portion of the esophagus. Carcinosarcomas and pseudosarcomas showed peculiar clinical and pathological characteristics. Overall prognosis was poor except in cases of pseudosarcoma and leiomyosarcoma.