Abstract
The DNA ploidy was determined by flow cytometry in 62 smooth muscle tumors of the G.I.tract (26 leiomyomas, 3 leiomyoblastomas, 33 leiomyosarcomas). The study aimed to define the diagnostic and prognostic values of DNA ploidy for smooth muscle tumors of the G.I. tract. The DNA ploidy was aneuploid in six of the 26 leiomyomas, in one of the three leiomyoblastomas, and in 18 of the 33 leiomyosarcomas. DNA aneuploidy was found significantly more often in leiomyosarcomas than in leiomyomas and leiomyoblastomas (p<0.05), but no evidence of clinical malignant behavior was found in the six leiomyomas or one leiomyoblastoma with DNA aneuploidy. In patients with leiomyosarcomas, DNA aneuploidy and a higher tumor grade were associated with significantly poorer survival rates (p<0.05), but neither the tumor size nor the mitotic index correlated with survival of the patients. The DNA ploidy patterns had little diagnostic value for smooth muscle tumors of the G.I. tract, but had significant prognostic values for leiomyosarcomas of the G.I. tract.
