Histopathologic Prognostic Factors in Stage I Leiomyosarcoma of the Uterus: A Detailed Analysis of 27 Cases.

Uterine leiomyosarcomas (Ut-LMSs) are aggressive tumors with an overall poor prognosis (15% to 25% 5-year survival rate). However, patients with stage I Ut-LMSs are reported to have a relatively better outcome when compared with the overall group with a 5-year survival rate ranging from 25% to 75%. The purpose of this study was to evaluate the histopathologic parameters that may impact outcome in stage I Ut-LMSs. Twenty-seven patients with stage I Ut-LMSs were identified from the files of 5 tertiary care hospitals between 1974 and 2006. Tumors were primarily staged based on pathologic information, supplemented with radiologic findings (10 cases) and clinical records (1 case). Patients with stage I tumors with no additional clinical or radiologic staging information were included in the study if no recurrence was documented after 6 months from the initial staging operation (16 cases). Clinicopathologic parameters that were statistically evaluated included age [mean, 54 y (37 to 73)], tumor size [mean, 9.5 cm (5.5 to 16)], cell type (17 spindled, 5 epithelioid, 2 myxoid, and 3 mixed), mitotic activity [mean count, 24 (4 to 69)/10 high-power fields], marked cytologic atypia (26 of 27 cases), tumor cell necrosis (12 of 27 cases), and lymphovascular invasion (6 of 27 cases). Follow-up was available for all the patients. Poor outcome was defined when patients either died of disease or were alive with disease. Overall, accounting for any length of follow-up, 16 of 27 (59%) patients with stage I Ut-LMSs had poor outcome; 7 died of disease (mean follow-up, 13 mo) and 9 were alive with disease (mean follow-up, 31 mo). The remaining 11 patients were alive and well with a mean follow-up of 48 months. However, at 2 years of follow-up by univariate analysis, only nonspindle morphology (