Exercise behavior and patient-reported outcomes in women with early breast cancer receiving locoregional radiation therapy

Abstract

Purpose: Radiation therapy is associated with acute treatment-related complications that can lead to decreased quality of life (QOL). Exercise has been shown in other cancer treatment settings to improve negative outcomes. We conducted a prospective pilot study to explore the association between exercise, patient-reported outcomes, and acute radiation therapy toxicities.

Methods and materials: Women receiving curative breast radiation therapy were enrolled. Each patient completed an exercise behavior/QOL survey before or during the first week of treatment and again during the last week of treatment. Exercise behavior was quantified with the Godin Leisure Time Exercise Questionnaire (metabolic equivalent [MET] hours per week). Measurements to evaluate upper extremity lymphedema and shoulder range of motion were completed. Skin toxicity was assessed weekly. Patient-reported outcomes were measured using standardized questionnaires.

Results: Forty-five patients were enrolled. Mean patient age was 54 (range, 28-73) years. Mean METs in the exercise cohort (≥9 METs/wk) was 21 per week (range, 11-38, n = 14); 3 per week (range, 0-8, n = 25) in the nonexercise cohort (<9 METs/wk). Women in the exercise cohort showed improvements in treatment-induced quality of life and fatigue (not significant) despite more extensive surgical, medical, and radiation treatment. No differences in treatment-related toxicities, pain, or sleep scores were noted. Lymphedema was mild (<3 cm) in the entire patient cohort.

Conclusions: The vast majority of current exercise oncology literature implicates physical activity as an independent predictor of QOL in cancer patients. Our study noted similar trends, but they were not statistically significant. This may be due to our finding that patient-reported outcomes with radiation therapy are relatively high compared with other treatment modalities and remain stable throughout treatment. Thus, it may be that radiation therapy has a limited impact on QOL in breast cancer patients. Exercise may be best used as a targeted therapy in patients at high risk for poor QOL or radiation-related toxicities at baseline.