A planned, prospective comparison of short-term quality of life outcomes among older patients with breast cancer treated with standard chemotherapy in a randomized clinical trial vs. an observational study: CALGB #49907 and #369901

ObjectivesPatients ≥ 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”).MethodsOlder 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.ResultsAnthracycline 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.ConclusionThere 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.