Exercise influence on taxane side effects in women with breast cancer

Taxane-based chemotherapy is frequently administered to treat breast cancer. However, side effects of taxanes include chemotherapy-induced peripheral neuropathy (CIPN) and cardiovascular complications, which negatively impact patient quality of life and long-term health. Exercise can significantly reduce cancer treatment side effects. However, information on exercise’s influence on taxane-specific side effects is limited. The primary aim of this dissertation was to evaluate the effect of exercise on taxane side effects, including CIPN and cardiovascular outcomes, in women with breast cancer. METHODS: Women with early-stage breast cancer were randomized to thrice-weekly exercise (EX) or usual care (UC) during taxane chemotherapy (4 cycles, 2-3 weeks apart). Patient-reported CIPN symptoms and quality of life (EORTC QLQ-C30 + CIPN20 subscale), clinical CIPN tests (vibration sensation and pinprick), patient-reported pain (Brief Pain Inventory) and cardiovascular outcomes, including heart rate and blood pressure at rest, and during and after submaximal exercise testing, were evaluated at baseline (pre-taxane chemotherapy) and end of chemotherapy. CIPN symptoms and quality of life were also evaluated at 0-3 days pre-chemotherapy cycle 4. RESULTS: Twenty-four women enrolled (EX: n=11, UC: n=13). Patient-reported CIPN symptoms were significantly worse by the end of chemotherapy in both groups for sensory (p<0.01) and motor symptoms (p=0.04), with a trend towards reduced sensory symptom progression among exercisers (p=0.08). Significantly more participants in the usual care group had impaired vibration sensation at 0-3 days pre-chemotherapy cycle 4 at the left interphalangeal joint (UC: 80%, EX: 10%, p<0.01), with a similar trend for the right interphalangeal joint (UC: 60%, EX: 10% p=0.06). Resting heart rate was significantly lower by the end of chemotherapy in the exercise group (EX: 71±2, UC: 77±2 bpm, p<0.05). The exercise group also had significantly lower heart rates during submaximal exercise testing (p