The impact of patients' age on breast cancer therapy and prognosis

Introduction:

Breast cancer (BC) patients aged younger than 36 or older than 69 years are underrepresented in clinical trials. Hence, we aimed to investigate how clinico-pathologic parameters, therapy and prognosis of early BC are affected by patients' age.

Methods:

Data of tumor and patient characteristics of 5829 patients with early BC (n(≤35y)= 293; n(36 – 69y)= 4501; n(≥70y)= 1035) were prospectively collected. Patients had been treated at the National Center for Tumor Diseases (NCT) and the certified Breast Unit of the University Hospital Heidelberg between 2003 and 2016.

Results:

Proportion of luminal type BC increases with patient age, while a vice versa effect was observed regarding Her2 overexpression and proportion of patients with TN and high-grade BC (p < 0.001). A higher rate of mastectomy (p < 0.001) was observed in patients aged ≥70y. Patients ≥70y with luminal B (79%; p = 0.001), Her2 (91%; p = 0.045) or TN (89%; p = 0.012) BC less often received chemotherapy. Individualized chemotherapy protocols were more common in patients aged ≥70y. Breast-cancer-specific-survival (BSS) and distant-disease-free-survival (DDFS) proved not to be different among patients aged ≤35y and > 35y, respectively. Comparing patients aged < 70y vs. ≥70y, however, we observed significantly reduced BSS (p = 0.002) and DDFS (p = 0.020) in patients aged ≥70y. This effect remained significant in multivariate analysis.

Conclusion:

Oncologic treatment is deescalated in older patients with early BC. Whether this observation is related to shortened BSS and DDFS needs to be interpreted with caution due to confounding factors like performance status and comorbidities. Nevertheless, even in multivariate analysis age ≥70y was associated with reduced disease-specific outcome.