Progesterone Receptor Expression Is an Independent Prognosticator in FIGO Stage I Uterine Leiomyosarcoma

Objectives: To analyze the clinical role of hormone receptors in a large uterine sarcomas series with long-term follow-up. Methods: Protein expression of estrogen receptor (ER) and progesterone receptor (PR) by immunohistochemistiy was studied in tissue microarrays from 294 patients diagnosed with uterine sarcoma in Norway from 1970 to 2000 and analyzed for an association with clinicopathologic parameters and outcome. Results: ER and PR were detected in 136 of 291 and 184 of 291 tumors (three noninformative cases each), respectively. Expression was unrelated to histology, patient age, tumor diameter, the degree of atypia, the presence of necrosis or vascular invasion, or mitotic counts. ER and PR expression was unrelated to survival in the analysis of the entire cohort. When survival analysis was confined to stage I leiomyosarcoma (n = 147), higher PR score was significantly related to longer overall survival (OS) (P = .042). Clinicopathologic prognosticators in this group were age (P = .041), tumor diameter (P = .001), and mitotic count (P = .007), with a trend for atypia (P = .087). In Cox multivariate analysis, PR score (P = .019), tumor diameter (P = .013), and mitotic count (P = .002) were independent prognosticators of OS. Conclusions: Hormone receptor expression is not informative of outcome in the analysis of uterine sarcomas of all stages and histologic types. PR expression identifies patients with longer survival in stage I leiomyosarcoma.