The relation between histological, tumor-biological and clinical parameters in deep and superficial leiomyosarcoma and leiomyoma

Purpose: Leiomyosarcomas (LMS) of deep and superficial tissues were examined to identify prognostic markers explaining their different biological behaviour and to define differences between cutaneous and subcutaneous LMS. LMS and leiomyomas (LM) of the skin were compared to find consistent differences that could aid in the (sometimes dif. cult) diagnosis. Patients: Material was obtained from 27 patients with a deep LMS, 14 with a superficial LMS, and 21 with a LM. Methods: Proliferation markers (mitotic and Ki-67 indices), DNA ploidy, size, grade, and the amount of apoptosis were studied. Statistical analysis was performed and survival curves were constructed by the Kaplan-Meier method and compared by the log-rank test. Results: Superficial LMS were smaller than deep LMS (p ＜ 0.05), and the overall survival of patients with a superficial LMS was better than with a deep LMS (p ＜ 0.05).Within the group of superficial LMS only entirely subcutaneous, and not cutaneous tumors metastasized. No differences were found in the other examined parameters. Proliferation and apoptotic indices were significantly higher in superficial LMS compared to superficial LM. Discussion: The difference in clinical outcome between patients with a superficial and deep LMS, seems to be related to site and size. The metastatic potential of subcutaneous LMS, however, seems to be related to location alone and not to size. The amount of apoptosis and proliferation can be used as additional criteria in the differentiation between superficial LMS and LM.