Purpose: To evaluate the impact of progesterone receptor (PR) status on estrogen receptor (ER)-positive and HER2-negative breast cancer.
Methods: A total of 1673 operable breast cancer patients, diagnosed from June 1984 to June 2011 were retrospectively reviewed and 400 patients with ER-positive and HER2-negative tumors were identified and evaluated. ER-positive and HER2-negative patients were classified into two groups: group A: ER+/PR-/HER2- and group B : ER+/PR+/HER2- according to PR status.
Results: Median follow-up was 14.2 years (range 10.1-18.2). The ratio of postmenopausal patients was significantly higher in group A (68.2%, p=0.015). Grade 1 tumor and stage I disease were significantly higher in group B (15%, p=0.007 and 15%, p=0.005, respectively). Mean overall survival (OS) and disease free survival (DFS) were significantly better in group B (15.3±1.5 years vs 8.7±0.8 years, p=0.032; 10.5±1.6 years vs 5.7±0.5 years, p=0.022) as compared with group A. Relative risk for recurrence and death were two-fold higher in group A (p=0.05 and p=0.01, respectively).
Conclusion: PR status exerts a significant impact on prognosis of ER+/HER2- breast cancer.