Early Changes in Physical Activity and Quality of Life With Thoracic Radiation Therapy in Breast Cancer, Lung Cancer, and Lymphoma

Abstract

The effects of thoracic radiation therapy (RT) on physical functioning and quality of life (QoL) are incompletely defined. We determined the associations between thoracic RT dose volume metrics, physical activity, and QoL in patients with cancer. Participants with breast cancer, lung cancer, or mediastinal lymphoma treated with radiation with or without chemotherapy were enrolled in a prospective, longitudinal cohort study. Data were collected pre-RT, immediately post-RT, and 5 to 9 months post-RT. At each timepoint, self-reported physical activity was assessed via the Godin-Shephard Leisure-Time Physical Activity Questionnaire, and QoL metrics were assessed via Functional Assessment of Chronic Illness Therapy Fatigue and Dyspnea Scales. Multivariable adjusted linear regression models were stratified by breast cancer alone and lung cancer and lymphoma combined. One hundred thirty participants were included in the study. In breast cancer (n = 80), each 1-Gy increase in mean heart dose was associated with worse Functional Assessment of Chronic Illness Therapy Fatigue scores (-1.0; 95% confidence interval [CI], -1.9 to -0.2; P = .021); similar associations were observed between V5 and fatigue (-2.5; 95% CI, -4.4 to -0.6; P = .010 for each 10% increase in V5). In lung cancer and lymphoma (n = 50), each 10% increase in V5 was associated with decreased physical activity (Godin-Shephard Leisure-Time Physical Activity Questionnaire score -2.3; 95% CI, -4.3 to -0.4; P = .017). Although the associations between baseline levels of physical activity and fatigue and dyspnea were of borderline significance in breast cancer alone (P < .10), increased physical activity over time was associated with improvements in fatigue and dyspnea across all cancer types (P < .05 for all). Higher cardiac RT dose was associated with worse fatigue and physical activity across breast cancer, lung cancer, and mediastinal lymphoma. Longitudinal increases in physical activity were associated with concurrent improvements in QoL measures. Strategies to increase physical activity and decrease cardiac RT dose may improve physical functioning and QoL for patients with cancer.