Objectives: Patients ≥ 65 years old ("older") are often not included in randomized clinical trials (RCT), but when they are, care in an RCT might improve quality of life (QoL). We conducted a prospective comparison of QoL among older women receiving standard chemotherapy from the same cooperative group physicians in an RCT vs. an observational study ("off-trial").
Methods: Older women with invasive, non-metastatic breast cancer (n=150 RCT; 530 off-trial) were included. Linear mixed-effects models tested associations between chemotherapy on- vs. off-trial and changes in EORTC (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire) QoL scores over 24 months, controlling for pre-treatment QoL, age, education, tumor factors, comorbidity, and other covariates.
Results: Anthracycline regimens were used by 58% of women treated on-trial vs. 54% of those treated off-trial. Women in the RCT reported an adjusted mean increase of 13.7 points (95% CI 10.2, 17.1) in global QoL at 24 months (vs. mid-treatment), while women treated off-trial had only an adjusted improvement of 7.0 points (95% CI 3.5, 10.4; p=.007 for difference in mean changes). Women in the RCT had significantly greater improvement in emotional function than those treated off-trial, controlling for baseline; they also had greater reductions in therapy side effects and fatigue at 24 months than women off-trial, controlling for covariates.
Conclusion: There may be different QoL trajectories for older women undergoing breast cancer chemotherapy on- vs. off-trial. If confirmed, the results suggest that the extra monitoring and communication within an RCT could provide the infrastructure for interventions to address symptoms and improve QoL for the growing older cancer population.
Keywords: Breast cancer; Chemotherapy; Observational studies; Older patients; Quality of life; Randomized clinical trials.
Copyright © 2013 Elsevier Inc. All rights reserved.