Abstract
PURPOSE: The German guideline for breast cancer recommends using chemotherapy (CHT) in patients with hormone receptor-positive and node-positive, invasive breast cancer. The aim of this study was to analyse the effects of CHT in this patient group on overall survival (OS) and distant metastases-free survival (DMFS), especially considering the 70-year threshold. METHODS: 1772 patients from the clinical cancer registry Regensburg (Germany) with hormone receptor-positive and node-positive, invasive breast cancer diagnosed between 2003 and 2013 were analysed in a retrospective cohort study. OS and DMFS were evaluated by means of Kaplan-Meier and multivariable Cox-regression method. Results were further examined according to age at diagnosis. RESULTS: The comparison of 1544 patients with CHT to 228 patients without CHT showed a significant benefit for CHT regarding 5-year OS (91.3% vs. 76.8%) and 5-year DMFS (86.7% vs. 74.4%, both p < 0.001). Likewise, better OS and DMFS were seen in patients aged < 70 years using CHT compared to patients without CHT of the same age. Patients aged ≥ 70 years with CHT had a minimal benefit regarding 5-year OS compared to patients without CHT, but no advantage considering DMFS. All results were confirmed in multivariable analyses except for patients being ≥ 70 years of age. CONCLUSION: Patients with hormone receptor-positive and node-positive, invasive breast cancer benefit from chemotherapy with regard to a significantly better overall and distant metastases-free survival, although chemotherapy use in patients aged ≥ 70 years results in a smaller benefit considering OS and no benefit considering DMFS.