Steroid hormone receptors (HRs), estrogen receptor (ER) and progesterone receptor (PR), are crucial biomarkers for clinical management in breast cancer. However, limited data are available regarding single HR-positive, making it difficult for treatment decision and survival prediction in these patients.
Breast cancer patients were retrieved in Surveillance, Epidemiology, and End Results database. Patients without ER, PR, or breast cancer-specific survival (BCSS) data were excluded. We stratified patients into ER+/PR+, ER+/PR-, ER-/PR+, and ER-/PR- groups. BCSS analysis was performed by Kaplan-Meier method. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).
This study included 823,339 breast cancer patients (553,165 [67.18%] ER+/PR+, 100,319 [12.18%] ER+/PR-, 13,368 [1.62%] ER-/PR+, and 156,547 [19.01%] ER-/PR-). Significant differences were detected between the four groups involving age, sex, race, tumor size, lymph node status, AJCC stage, grade, histology type, and HER2 status. Survival analyses showed that the ER/PR status were significantly associated with BCSS; the estimated mean BCSS months was 261.3, 241.2, 233.6, and 227.6 for ER+/PR+, ER+/PR-, ER-/PR+, and ER-/PR-, respectively (p < 0.001). Compared with ER+/PR+, ER+/PR- (HR, 1.67; 95% CI, 1.64-1.70) and ER-/PR + (HR, 1.83; 95% CI, 1.74-1.92) patients were associated with poor BCSS. When compared with ER-/PR- (vs. ER+/PR-, HR, 1.39; 95% CI, 1.37-1.42 and vs. ER-/PR+, HR, 1.12; 95% CI, 1.08-1.16), ER+/PR- and ER-/PR+ patients had a better BCSS. ER-/PR + (HR, 1.17; 95% CI, 1.13-1.22) was significantly associated with poorer BCSS than ER+/PR-. In multivariable Cox regression analysis, when compared with ER+/PR+, the risk of breast cancer-specific death increased 37% for ER+/PR- (HR, 1.37; 95% CI, 1.34-1.39), 59% for ER-/PR + (HR, 1.59; 95% CI, 1.53-1.65), and 76% for ER-/PR- (HR, 1.76; 95% CI, 1.73-1.78) (p for trend<0.001).
There are significant distinctions between ER+/PR+, ER+/PR-, ER-/PR+, and ER-/PR- phenotype. Importantly, the clinical and prognostic features of single HR-positive breast cancer should be re-recognized and re-oriented.
Guosheng Ren.
National Natural Science Foundation of China.
All authors have declared no conflicts of interest.