Factors influencing treatment patterns of breast cancer patients age 75 and older

PURPOSES: To retrospectively determine the factors influencing treatment decisions in older breast cancer patients at a single center. EXPERIMENTAL DESIGN: 216 patients age > or = 75 seen in post-treatment follow-up between January, 1997 and June, 2000 were identified in the Memorial Sloan-Kettering breast cancer database. Eligible patients were > or = 75 years old at diagnosis, had a diagnosis of stage I, II, or III breast cancer, and received their follow-up care at Memorial Sloan Kettering Cancer Center. A retrospective chart review was performed. Patients were stratified by: (1) prognostic factors (age (75-79 or > or = 80), Charlson comorbidity score, tumor size, nodal status, stage, ER, PR, creatinine, albumin, hemoglobin, and liver function tests), (2) local treatment (lumpectomy, axillary lymph node dissection (AxLND), radiation (XRT), modified radical mastectomy (MRM)) and (3) systemic treatment (tamoxifen, chemotherapy). Combined local treatment was defined as (a) lumpectomy, AxLND, XRT or (b) MRM, AxLND, XRT (if tumor > or = 5 cm or > or = 4+ lymph nodes). RESULTS: 96 patients were eligible for this study: 46 patients (75-79 years); 50 patients (> or = 80 years). The majority of patients (74%) were treated with lumpectomy but those > or = 80 were less likely to receive XRT (94% age 75-80; 45% age >80; P<0.01). Patients > or = 80 were also less likely to receive AxLND (94% age 75-79; 62% age > or = 80; P<0.01). A logistic regression model identified two independent prognostic variables for not receiving combined local treatment: increased age (P<0.01) and increased comorbidity score (P=0.01). Increased age did not correlate with increased comorbidity (P=0.48). 5.2% of patients received adjuvant chemotherapy (all age <80). 83% of ER positive patients received tamoxifen (89% age 75-79; 79% age >80). CONCLUSION: We hypothesize that both comorbidity and age play a significant role in influencing treatment decisions in the older breast cancer patient but these two variables are not necessarily correlated. Prospective studies are needed to determine the relative impact of these variables.