PROGNOSTIC FACTORS IN ELDERLY WOMEN WITH METASTATIC BREAST-CANCER TREATED WITH TAMOXIFEN - AN ANALYSIS OF PATIENTS ENTERED ON 4 PROSPECTIVECLINICAL-TRIALS

BACKGROUND. Information regarding prognostic factors and survival in e lderly women with metastatic breast cancer treated with tamoxifen is l imited. METHODS. The data from 4 prospective clinical trials were anal yzed, including information on 396 postmenopausal women with advanced breast cancer who received tamoxifen as initial therapy for metastatic disease. Emphasis was placed on 184 elderly patients (age greater tha n 65 years) to characterize the response to therapy, time to progressi on (TTP), overall survival (OS), prognostic factors, and treatment-rel ated toxicity. RESULTS. Among 363 patients with measurable or evaluabl e disease, the objective response rates were higher in the elderly pat ients (46% versus 33%, P = 0.06); but age did not achieve significance in a logistic regression analysis (P = 0.1). The median TTP (10.5 mon ths versus 6.2 months, log rank P = 0.002) and OS (35.7 months versus 28.8 months, log rank P = 0.02) were superior in the elderly cohort. I n multivariate analysis, age at diagnosis approached statistical signi ficance (P = 0.055) for TTP but was not significant for OS (P = 0.17). Among elderly patients, disease free interval (DFI) (greater than 5 y ears), dominant disease site (soft tissue), prior adjuvant chemotherap y, positive estrogen/progesterone receptor (ER/PgR) and performance st atus (PS) were independent prognostic factors. Hot flashes were common in both younger and older cohorts (25% versus 33%, P = 0.14), while a norexia (14% versus 22%, P = 0.04) and mood changes (2% versus 6%, P = 0.03) were more common in the elderly patients. CONCLUSIONS. There wa s no indication that elderly women with metastatic breast cancer treat ed with tamoxifen have a poorer outcome with regard to response rate,T TP or OS; in fact, they appeared to have a slightly better prognosis a lthough this was not significant after adjustment for other prognostic factors. In elderly patients, DFI, PS, positive ER or PGR, and domina nt disease site are independent prognostic factors. (C) 1996 American Cancer Society.