Objective: The aim of this study was to evaluate the behavior of endometrial stromal sarcomas (ESS) in relation to their clinical and pathologic features and to identify possible prognostic factors.
Methods: Thirty-one patients with histologically proven ESS were included in the analysis. Endometrial stromal sarcoma is characterized by proliferations composed of cells with endometrial stromal cell differentiation. A breakpoint of 10 mitoses per 10 high-power fields was used in the statistical analysis to distinguish between low-grade and high-grade endometrial stromal sarcoma and to evaluate the prognostic value of mitotic count in patients with ESS.
Results: The median follow-up time was 72 months (range 34-110). The median overall survival of the 31 patients was 127 months, resulting in a 5-year overall survival rate of 62%. Adjuvant therapy was administered to 25 patients; among those, 20 patients received postoperative radiotherapy and 5 patients received chemotherapy. Ten of the irradiated patients and 3 patients undergoing chemotherapy developed disease recurrence. Concerning the response rate to adjuvant chemotherapy, 1 patient showed a complete response, 1 patient a partial response, 1 patient stable disease, and 2 patients progressive disease. Altogether, 14 patients developed recurrent disease with a median disease-free survival of 11 months (range 5-60). Twelve patients died of the disease. A univariate model revealed that early tumor stage (P < 0.0007), low myometrial invasion (P < 0.008), and low mitotic count (P < 0.005) were associated with a lengthened overall survival in patients with endometrial stromal sarcoma. Age and adjuvant therapy did not influence overall survival of patients with ESS.
Conclusion: Early tumor stage, low myometrial invasion, and low mitotic count are associated with a lengthened overall survival in patients with ESS.
Copyright 2001 Academic Press.