TRADE-OFFS BETWEEN SURVIVAL AND BREAST PRESERVATION FOR 3 INITIAL TREATMENTS OF DUCTAL CARCINOMA-IN-SITU OF THE BREAST

Purpose: To assess the trade-offs between survival and breast preserva tion of currently accepted approaches for ductal carcinoma-in-situ (DC IS) of the breast. Patients cmd Methods: Decision analysis was perform ed using the Markov model of hypothetical cohorts of 55-year-old white women with nonpalpable mammographic abnormalities found to be DCIS. S trategies were breast-conserving surgery (BCS), BCS with 50-Gy radiati on (RT) or initial mastectomy. Recurrence rates were derived from the published literature. Main outcomes were overall, breast cancer-free, and event-free survival plus years of both breasts preserved. Results: Using the conditions defined in this model, the actuarial survival ra tes at 10 and 20 years were 98.7% and 74.1% for the initial mastectomy strategy, 91.0% and 72.1% for BCS plus RT, and 89.6% and 68.2% for BC S alone. At 20 years, the initial mastectomy strategy also had a great er breast cancer-free survival rate of 74.5%, compared with 63.3% for BCS plus RT, or 46.8% for BCS alone, However, BCS alone had the highes t survival rate with both breasts preserved (64.2%) compared with BCS plus RT (56.0%) or initial mastectomy (0%). Of the breast-conserving s trategies at 20 years, the breast event-free survival rate (no invasiv e cancer or DCIS) was greater for BCS plus RT (47.2%) compared with BC S alone (28.4%), Using just survival as the primary end point, mastect omy is the optimal strategy by a small margin. However, if quality-adj usted survival is at issue, mastectomy is the choice only if the yearl y reduction in quality of life due to mastectomy is less than 1%. Conc lusion: BCS with or without radiation compared with mastectomy as init ial management of DCIS of the breast trades a slight decrease in survi val rates for the value of breast preservation, This model should aid clinicians in matching treatments to their patients' preferences.