Side effects of adjuvant chemotherapy and their impact on outcome in elderly breast cancer patients: a cohort study

Aim: Breast cancer patients over the age of 65 are more likely to suffer chemotherapy side effects, with premature discontinuation, which negatively affects survival.Methods:We conducted a retrospective cohort study enrolling breast cancer patients; dose reductions or interruptions of chemotherapy have been collected, as well as side effects. Progression-free survival was determined by Kaplan-Meier and evaluated for its association with reduction/suspension. The study included 128 women (median age: 71).Results:Nineteen patients experienced cardiotoxicity, while dosage of chemotherapy was reduced in 23 patients (18.0%), and 14 (10.9%) had premature interruptions. Dose reduction/interruptions were associated with numerically worse progression-free survival (78.2 vs 94.8 months; p = 0.10).Conclusion:Reduction/discontinuation of chemotherapy due to side effects affected nearly 30% of our population, potentially worsening outcomes. Lay abstract: Breast cancer patients over the age of 65 are more likely to suffer chemotherapy side effects, which negatively affect survival. We conducted a retrospective study of 128 elderly breast cancer patients, collecting changes in chemotherapy doses and schedules, as well side effects. Progression-free survival (PFS) was calculated and evaluated for its association with reduction/suspension. Nineteen patients experienced cardiotoxicity, while dosage of chemotherapy was reduced in 23 patients (18.0%), and 14 (10.9%) had premature interruptions. Dose reduction/interruption were associated with numerically worse PFS (78.2 vs 94.8 months; p = 0.10). Occurrence of reduction/discontinuation of chemotherapy and cardiotoxicity in this population could potentially worsen outcomes.