[DNA flow cytometry in smooth muscle tumors of the gastrointestinal tract].

DNA ploidy of 45 smooth muscle tumors of the G.I. tract was determined by flow cytometry and correlated with clinical features and prognosis. The sites of the tumors were: esophagus (1), stomach (24), small intestine (12), large intestine (6), liver (1) and pancreas (1). The histologic type was leiomyoma in 14, leiomyosarcoma in 29, and leiomyoblastoma in 2. DNA aneuploidy was more frequent in leiomyosarcoma (17/29) than leiomyoma (5/14), but the difference was not statistically significant. One leiomyoblastoma was diploid and the other was aneuploid. No patients with leiomyoma died. In patients with leiomyosarcomas, 5-year survival was significantly poorer in those with aneuploid tumors (38%) than in those with diploid tumors (83%). There was no correlation between DNA ploidy and clinico-pathological features of tumors. The present study disclosed that DNA ploidy is a prognostic variable, independent of other variables.