Association Between Age at Diagnosis and Disease-Specific Mortality Among Postmenopausal Women With Hormone Receptor-Positive Breast Cancer

Context In addition to classic tumor-related prognostic factors, patient characteristics may be associated with breast cancer outcome. Objective To assess the association between age at diagnosis and breast cancer outcome in postmenopausal women with hormone receptor-positive breast cancer. Design, Setting, and Patients Study analysis of 9766 patients enrolled in the TEAM (Tamoxifen Exemestane Adjuvant Multinational) randomized clinical trial between January 2001 and January 2006. Age at diagnosis was categorized as younger than 65 years (n=5349), 65 to 74 years (n=3060), and 75 years or older (n=1357). Main Outcome Measures Primary end point was disease-specific mortality; secondary end points were other-cause mortality and breast cancer relapse. Results During median follow-up of approximately 5.1 years, there were a total of 1043 deaths. Disease-specific mortality, as a proportion of all-cause mortality, decreased with categorical age group (78% [= 75 years]; P