Routine treatment and outcome of breast cancer in younger versus elderly patients: results from the SENORA project of the prospective German TMK cohort study

Abstract

Purpose: There is an ongoing discussion about 'undertreatment' of breast cancer in elderly patients. Due to low accrual into clinical trials, level 1 evidence is scarce. We report prospective data of elderly patients with breast cancer treated by medical oncologists in Germany.

Methods: The SENORA project within the prospective cohort study TMK (Tumour Registry Breast Cancer) was conducted in 82 centres from 2007-2015. Among 2316 patients, half were enrolled with curative and half with palliative treatment intention. Overall, 478 patients (21%) were aged ≥ 70.

Results: In the adjuvant setting, elderly patients aged ≥ 70 had more advanced tumour stages at diagnosis and a higher prevalence of comorbidities than younger patients. Elderly patients received adjuvant chemotherapy less frequently, yet the 3-year disease-free survival was similar (86% vs. 88%). In the palliative setting, elderly patients more frequently received endocrine therapy and less frequently chemotherapy. Their median overall survival [24.9 months, 95% CI (confidence interval) 20.0-30.2] was significantly shorter than that of younger patients (39.7 months, 95% CI 34.9-44.2). A Cox proportional hazards model showed a significantly increased risk of mortality for: age ≥ 70 at start of therapy, negative HR- or HER2-status, higher number of metastatic sites, more comorbidities and high tumour grading at diagnosis.

Conclusions: Our results shed light on the routine treatment of elderly patients with breast cancer. A regression model demonstrated that age is but one of various prognostic factors determining the shorter overall survival of elderly patients.

Keywords: Aged; Breast neoplasms; Cohort studies; Outcome assessment; Prognosis; Registries.

Conflict of interest statement

Conflict of interest

TF declares a consultant/advisory role for Teva, Novartis, Sanofi-Aventis, Roche and Boehringer Ingelheim. AK has received travel expenses from Roche, Novartis, Celgene and Amgen for attendance of advisory boards. NM has received travel expenses from Roche, Novartis, Celgene and Amgen for attendance of advisory boards and scientific meetings. All other authors declare no conflict of interest concerning the topic of this publication.

Research involving human and animal rights

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

Figures

Fig. 1

Cohort definition. Number of patients enrolled in the TMK, split up according to the neoadjuvant, adjuvant or palliative treatment intention as well as to the age at start of therapy. Prospectively enrolled patients signed the informed consent no longer than 6 weeks after start of treatment

Fig. 2

Treatment of breast cancer for patients aged a Proportion of patients receiving breast conserving surgery (BCS) in the adjuvant treatment setting. The proportion of patients receiving radiotherapy (RT) is calculated for all patients receiving BCS. b Proportion of patients receiving mastectomy (Mx) in the adjuvant treatment setting. The proportion of patients receiving radiotherapy is calculated for all patients receiving Mx. c Proportion of patients receiving taxane-based chemotherapy (of all patients receiving chemotherapy). d Proportion of patients receiving anti-HER2-therapy (of all patients with HER2-positive tumours). e Proportion of patients with HR-positive tumours receiving systemic chemotherapy and/or endocrine therapy. In the adjuvant treatment setting, patients receiving chemotherapy and endocrine therapy as well as patients receiving only chemotherapy were added up. 114 younger patients (15.3%) and 12 elderly patients (11.9%) received chemotherapy without endocrine therapy. Error bars represent the 95% confidence interval (CI) Abbreviations: BCS breast conserving surgery, CI confidence interval, CTx chemotherapy, ET endocrine therapy, HER2 human epidermal growth factor receptor 2, HR hormone receptor, Mx mastectomy, pos positive, pts patients, RT radiotherapy

Fig. 3

Survival of patients aged a DFS for the patients with (neo)adjuvant treatment intention, b OS for the patients with palliative treatment intention, c Disease-specific survival for the patients in the palliative setting. Abbreviations: CCI Charlson Comorbidity Index, CI confidence interval, DFS disease-free survival; DSS disease-specific survival, OS overall survival

Fig. 4

Multivariate regression analysis. Cox proportional hazards model for overall survival. Bold writing: significant results (p < 0.05). *Metastasis at diagnosis was documented either synchronous (M1) or metachronous (M0). Abbreviations: BMI body mass index, CCI Charlson Comorbidity Index, CI confidence interval, HR hazard ratio, HER2 human epidermal growth factor receptor 2, metachr metachronous, synchr synchronous