Physical activity during cancer treatment (PACT) study: Short- and long-term effects on fatigue of an 18-week exercise intervention during adjuvant chemotherapy in patients with breast or colon cancer

Background: Fatigue is a major problem of cancer patients. Thirty percent of cancer survivors still report serious fatigue three years post- treatment. Physical exercise during cancer treatment might reduce symptoms of fatigue. The primary aim of the present multicenter randomized controlled trial was to compare the short- and long-term effects on fatigue of an 18-week exercise intervention during adjuvant chemotherapy for breast or colon cancer patients. Methods: 237 patients (204 breast and 33 colon cancer) were randomly assigned to supervised aerobic and resistance exercise (n=119) or usual care (n=118). In addition to the supervised exercise, the intervention group was asked to be physical active for 30 minutes a day on 3 other days. Fatigue was assessed with the validated Multidimensional Fatigue Inventory at baseline (i.e. within 6 or 10 weeks after diagnosis for breast and colon cancer patients, respectively), after 18 weeks and after 9 months. Results: Intention to treat analyses using linear mixed-effects models showed a significant effect over time in favor of the intervention group for general and physical fatigue (p=0.001 and 0.02, respectively). Changes of general and physical fatigue were -0.90 (95% confidence interval: -1.77 to -0.04) and -1.24 (2.17 to -0.32) from baseline to 18 weeks and -1.12 (-2.01 to -0.22) and -0.66 (-1.62 to 0.30) from baseline to 9 months, respectively. Effects for mental fatigue, reduced activity and motivation were not significantly different. Conclusions: The 18-week exercise program during adjuvant treatment for breast or colon cancer showed positive results on general and physical fatigue directly after the intervention and also 4 1/2 months later. Hence, exercise might be a beneficial addition to routine cancer care during adjuvant cancer treatment.