Impact of Exercise on Chemotherapy Tolerance and Survival in Early-Stage Breast Cancer: A Nonrandomized Controlled...

Available preliminary evidence is conflicting on whether exercise can positively influence antineoplastic treatment tolerance and in turn improve survival.

This study compared chemotherapy treatment tolerance and survival among women receiving adjuvant chemotherapy for early-stage breast cancer who participated in a single-arm trial of supervised aerobic and resistance exercise programming versus a historical cohort that did not receive structured exercise programming.

The exercise group (EX; n=73) and control group (CTR; n=85) participants were matched on age and treatment and balanced on medical history, cancer diagnosis, and body mass index. Attendance in the EX group was 64% ± 27% of 3 offered sessions per week. For all chemotherapy agents combined, the relative risk (RR) of a chemotherapy dose reduction (RR, 0.78; 95% CI, 0.54-1.11) or delay (RR, 1.05; 95% CI, 0.62-1.80) did not differ between groups. However, the EX group had reduced relative and absolute risks of a dose reduction in doxorubicin by 60% and 18%, respectively. For all agents combined, there were no differences between groups in risk of anemia, neutropenia, or weight gain. In the EX group, dose reductions due to neutropenia (P=.027), other infections (P=.049), and fatigue (P=.037) were less common, whereas mucositis was more common (P=.023), compared with the CTR group. The EX group had reduced relative and absolute risks of weight gain on the docetaxel + cyclophosphamide regimen by 38% and 30%, respectively. After a median follow-up of 70 months (range, 54-84 months), there was no difference between the EX and CTR groups in disease-free survival events (n=8 [11%] vs n=9 [11%], respectively; log-rank test, P=.78) or overall survival events (n=5 [7%] vs n=6 [7%], respectively; log-rank test, P=.974).

Overall, exercise programming during adjuvant chemotherapy does not appear to impact treatment tolerance or survival in women receiving common modern regimens of adjuvant chemotherapy for early-stage breast cancer. However, exercise may provide selective benefits, depending on the treatment regimen received.