Randomized Trial of Standard Adjuvant Chemotherapy Regimens Versus Capecitabine in Older Women With Early Breast Cancer: 10-Year Update of the CALGB 49907 Trial
- 10 September 2019
- journal article
- research article
- Published by American Society of Clinical Oncology (ASCO) in Journal of Clinical Oncology
- Vol. 37 (26), 2338-2348
- https://doi.org/10.1200/jco.19.00647
Abstract
Older women with breast cancer remain under-represented in clinical trials. The Cancer and Leukemia Group B 49907 trial focused on women age 65 years and older. We previously reported the primary analysis after a median follow-up of 2.4 years. Standard adjuvant chemotherapy showed significant improvements in recurrence-free survival (RFS) and overall survival compared with capecitabine. We now update results at a median follow-up of 11.4 years. Patients age 65 years or older with early breast cancer were randomly assigned to either standard adjuvant chemotherapy (physician’s choice of either cyclophosphamide, methotrexate, and fluorouracil or cyclophosphamide and doxorubicin) or capecitabine. An adaptive Bayesian design was used to determine sample size and test noninferiority of capecitabine. The primary end point was RFS. The design stopped accrual with 633 patients at its first sample size assessment. RFS remains significantly longer for patients treated with standard chemotherapy. At 10 years, in patients treated with standard chemotherapy versus capecitabine, the RFS rates were 56% and 50%, respectively (hazard ratio [HR], 0.80; P = .03); breast cancer–specific survival rates were 88% and 82%, respectively (HR, 0.62; P = .03); and overall survival rates were 62% and 56%, respectively (HR, 0.84; P = .16). With longer follow-up, standard chemotherapy remains superior to capecitabine among hormone receptor–negative patients (HR, 0.66; P = .02), but not among hormone receptor–positive patients (HR, 0.89; P = .43). Overall, 43.9% of patients have died (13.1% from breast cancer, 16.4% from causes other than breast cancer, and 14.1% from unknown causes). Second nonbreast cancers occurred in 14.1% of patients. With longer follow-up, RFS remains superior for standard adjuvant chemotherapy versus capecitabine, especially in patients with hormone receptor–negative disease. Competing risks in this older population dilute overall survival benefits.This publication has 44 references indexed in Scilit:
- Comprehensive geriatric assessment for older women with early breast cancer – a systematic review of literatureWorld Journal of Surgical Oncology, 2012
- Comparisons between different polychemotherapy regimens for early breast cancer: meta-analyses of long-term outcome among 100 000 women in 123 randomised trialsThe Lancet, 2012
- Quality of Life of Older Patients With Early-Stage Breast Cancer Receiving Adjuvant Chemotherapy: A Companion Study to Cancer and Leukemia Group B 49907Journal of Clinical Oncology, 2011
- Adherence and Persistence With Oral Adjuvant Chemotherapy in Older Women With Early-Stage Breast Cancer in CALGB 49907: Adherence Companion Study 60104Journal of Clinical Oncology, 2010
- Adjuvant Chemotherapy in Older Women with Early-Stage Breast CancerThe New England Journal of Medicine, 2009
- Docetaxel With Cyclophosphamide Is Associated With an Overall Survival Benefit Compared With Doxorubicin and Cyclophosphamide: 7-Year Follow-Up of US Oncology Research Trial 9735Journal of Clinical Oncology, 2009
- Proposal for Standardized Definitions for Efficacy End Points in Adjuvant Breast Cancer Trials: The STEEP SystemJournal of Clinical Oncology, 2007
- Differences in Management of Older Women Influence Breast Cancer Survival: Results from a Population-Based Database in SwedenPLoS Medicine, 2006
- Censoring distributions as a measure of follow‐up in survival analysisStatistics in Medicine, 1986
- Nonparametric Estimation from Incomplete ObservationsJournal of the American Statistical Association, 1958