Immunohistochemical expression of estrogen and progesterone receptors and outcomes in patients with newly diagnosed uterine leiomyosarcoma

Abstract

Objective: We assessed the IHC expression of ER and PR and their prognostic significance in uterine leiomyosarcoma (LMS).

Methods: We identified 43 "high-grade" uterine LMS cases from 7/82-7/07 for whom ER/PR IHC analysis was performed at initial diagnosis at our institution.

Results: Disease was confined to the uterine body in 20/43 (47%). Eighteen (42%) of 43 were ER(+); 17/42 (41%) were PR(+). At last follow-up, 33 (77%) had recurred or progressed, and 23 (54%) had died. PR expression was associated with improved progression-free survival (PFS; P=0.002) and overall survival (OS; P=0.03) overall; ER expression was not. After adjusting for stage, ER expression was associated with PFS (P=0.01), not OS (P=0.3), and PR expression maintained a significant association with PFS (P=0.002) and approached a significant association with OS (P=0.05). Neither ER nor PR expression was associated with outcome in cases with disease outside the uterine body. In cases with confined disease, median PFS for ER(+) or PR(+) cases was not reached compared to 16.9 months for ER(-) cases (95% CI: 8.1-25.7; P=0.03) and 13.5 months for PR(-) cases (95% CI: 5.9-21.1; P=0.001). Only 1/10 PR(+) cases recurred and died; 9/10 PR(-) cases recurred, and 5 died. Two of 9 ER(+) cases recurred and died; 8/11 ER(-) cases recurred, and 4 died.

Conclusion: ER/PR expression is associated with survival outcomes in patients with high-grade uterine LMS confined to the uterine body. PR expression seems capable of identifying cases confined to the uterine body, which have better outcomes.