LEIOMYOSARCOMA IN SOFT-TISSUE - EXAMINATION OF P53 STATUS AND CELL PROLIFERATING FACTORS IN DIFFERENT LOCATIONS

The biological behavior of soft tissue leiomyosarcoma varies with its location: tumors in deep soft tissue show a worse prognosis than those in superficial soft tissue, In this study, ive analyzed cell prolifer ating factors (mitotic and Ki-67 indices) and the p53 status of both t ypes of leiomyosarcoma (37 cases) to evaluate the possibility that the se factors may serve as indicators in prognosis. Expression of both of the cell proliferating factors were higher in the superficial type, b ut these differences were not significant. The incidence of abnormal p 53 detected by immunohistochemistry and mutation analysis was also hig her in the superficial type, but, again, no significant difference was observed. Abnormal p53 and a high Ki-67 index in the deep type, and a large tumor size (>6 cm) in the superficial type may be useful as pro gnostic factors, Interestingly, all of the superficial cases who died of the disease showed abnormal p53. In conclusion, these two types of leiomyosarcoma are essentially the same, and their location remains a good prognostic factor, Furthermore, abnormality of the p53 gene was r elated to a poor prognosis regardless of the tumor's anatomic location . Copyright (C) 1998 by W.B. Saunders Company.