Impact of age on indication for chemotherapy in early breast cancer patients: results from 104 German institutions from 2008 to 2017

Purpose Today, the decision to treat patients with chemotherapy for early breast cancer (EBC) is made based on the patient’s individual risk stratification and tumor biology. In cases with chemotherapy indication, the neoadjuvant application (NACT) is the preferred option in comparison with primary surgery and adjuvant chemotherapy (ACT). Age remains a relevant factor in the decision-making process. The aim of the present study was to illustrate the impact of age on the use of systemic therapy in clinical routine. Methods The study separately analyzed chemotherapy use among six age cohorts of EBC patients who had been treated at 104 German breast units between January 2008 and December 2017. Results In total, 124,084 patients were included, 46,279 (37.3%) of whom had received chemotherapy. For 44,765 of these cases, detailed information on treatment was available. Within this cohort, chemotherapy was administered as NACT to 14,783 patients (33.0%) and as ACT to 29,982 (67.0%) patients. Due to the higher prevalence of unfavorable tumor subtypes, younger patients had a higher rate of chemotherapy (≤ 29y: 74.2%; 30–39y: 71.3%) and a higher proportion of NACT administration ( ≤ 29y: 66.9%; 30–39y: 56.0%) in comparison with elderly patients, who had lower rates for overall chemotherapy (60–69y: 37.5%; ≥ 70y: 17.6%) and NACT (60–69y: 25.5%; ≥ 70y: 22.8%). Pathologic complete response was higher in younger than in older patients (≤ 29y: 30.4% vs. ≥ 70y: 16.7%), especially for HER2− subtypes. Conclusion The data from the nationwide German cohort reveal relevant age-dependent discrepancies concerning the use of chemotherapy for EBC.