Risk Evaluation of Early-stage Hormone Receptor-positive and Human Epidermal Growth Factor Receptor 2-negative Breast Cancer Patients: a Population-based Study From Taiwan

Abstract PURPOSE: To assess the prognostic value of the Dutch criteria for patients with early-stage hormone receptor-positive and human epidermal growth factor receptor 2-negative breast cancer from the Taiwan Cancer Database. PATIENTS AND METHODS:We included 8,295 patients with early-stage node-negative breast cancer who underwent surgery during January 2008–December 2012. Patients were stratified into low- and high-risk groups based on the Dutch criteria. The Kaplan–Meier method and log-rank test were used to estimate the difference in breast cancer-specific survival (BCSS) and overall survival (OS) between groups. Multivariable analysis was used to evaluate the prognostic value of the Dutch criteria.RESULTS: Overall, the low-risk and high-risk groups comprised 5,375 and 2,920 patients, respectively. In the low- and high-risk groups, the 5-year BCSS rate was 99.6% and 98.2% (P<0.0001) and the 5-year OS rate was 98.3% and 96.8% (P<0.0001), respectively. The hazard ratio for BCSS was 4.18 (95% confidence interval [CI], 2.63–6.63, P<0.0001), and the hazard ratio for OS was 1.94 (95% CI, 1.48–2.55); both were significantly poorer in the high-risk group than in the low-risk group. In the low-risk group, the 5-year BCSS and OS of patients who did and did not receive adjuvant chemotherapy were similar (99.5% versus 99.6% [P=0.927] and 98.8% and 98.1% [P=0.0683], respectively). CONCLUSIONS: The prognosis of low-risk patients as classified using the Dutch criteria is excellent with or without adjuvant chemotherapy. The benefit of multi-gene testing for chemotherapy decision-making might be minimal in these patients.