Age alone or Charlson comorbidity index – what guides anticancer treatment choice in newly diagnosed, non-metastatic breast cancer in the real life setting?

Breast cancer is the the most common malignancy in woman and its frequency increases with age. The aim of the study was to asses if age itself impacts treatment choice in non-metastatic breast cancer patients and is associated with increased treatment toxicity in a real life observational setting. We also investigated whether Charlson comorbidity index values were correlated with PFS and OS. We conducted a retrospective analysis of medical records of 730 patients with newly diagnosed, non-metastatic breast cancer, treated in Maria Skłodowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch between 2007 and 2013. This analysis is preliminary, since the data collection is not completed yet. 244 patients were above 65 years old and 147 – above 70 years old. Variables included in uni- and multivariate analysis were: age, ECOG-PS, clinical stage of the disease, subtype of breast cancer (according to St Gallen 2015 classification). Older patients or in poor ECOG-PS were less likely to receive preoperative chemotherapy (p = 0.0073 and p < 0.001, respectively) or undergo surgery (p = 0.01 and p < 0.001, respectively). Older age (p < 0.0001) and luminal subtype of breast cancer (p < 0.0001) were associated with lower chance of adjuvant chemotherapy. In older patients (p < 0.0001) with poor PS (p = 0.04) hormonotherapy as the only treatment method was chosen significantly more common. Older patients were more likely to experience hematological toxicities (p = 0.03), including grade 3-4 toxicities (p = 0.04), after chemotherapy. Nausea and vomiting were significantly less common among older patients receiving chemotherapy (p = 0.03). The independent prognostic factor for shorter PFS was advanced pathological stage (p = 0.002) and for shorter OS – patients age (p = 0.02) and HER2 overexpression (p = 0.006). Higher Charlson comorbidity index was significantly correlated with shorter PFS (p < 0.0001) and OS (p < 0.0001), independent of patients age. According to this preliminary analysis, older breast cancer patients are less likely to receive chemotherapy or undergo surgery. Charlson comorbidity index was strongly correlated with shorter PFS and OS.