Objective: The purpose of this study was to investigate the expression patterns and prognostic impact of estrogen receptor (ER), progesterone receptor (PR) and their combinations in young patients with ovarian carcinomas (OC) in China.
Methods: We collected data on 86 patients diagnosed of OC younger than or equal to 40 years of age with a long clinical follow-up. Immunohistochemical staining was performed to assess ER and PR expression in paraffin-embedded ovarian cancers. Samples in which more than 10% of cells showed stained nuclei were interpreted as positive for the particular receptor. Survival rates (Kaplan-Meier method) were compared by the log rank test. A multivariate analysis (Cox proportional hazards) was used to determine the independent effect of each variable on survival.
Results: ER were found positive in 64.0% of all cases but most highly expressed in serous types (P=0.047). PR-positive expression accounted for 57.0% of all cases and elevated in early FIGO stages and well-differentiated diseases (P=0.004 and 0.012, respectively). The expression of PR, but not ER, was associated with favorable survival in Kaplan-Meier survival analyses (P<0.001). The ER+PR+ combination, which was associated with low FIGO stages (P=0.012) and low tumor grade (P=0.046), showed a superior course of patients' overall survival compared with all other combinations (5-year survival rate 95.0% vs. 73.4%, log rank P=0.001). PR status (hazard ratio 1.93, P<0.001) together with FIGO stage (hazard ratio 2.19, P<0.001) were proved to be independent prognostic factors by multivariate analysis.
Conclusions: This study indicates that the expression of PR, especially the ER+PR+ phenotype predicts a favorable clinical outcome for young patients of OC.