A prospective analysis of surgery and survival in stage IV breast cancer (TBCRC 013).

1006Background: TBCRC 013 is a multicenter prospective registry study evaluating the role of surgery for the primary tumor in de novo Stage IV disease. Methods: From 7/09-4/12, 127 pts from 14 sites were enrolled in 2 cohorts (A: Stage IV with intact primary (n = 112); B: metastases within 3 mos of primary surgery (n = 15)). All patients received 1st-line systemic therapy per treating physician. In Cohort A, patients classified as responders to 1st-line therapy (partial, complete, or stable distant disease) were referred to discuss elective surgery. Patient and tumor characteristics, response to systemic therapy and surgery of the primary tumor were correlated with 3yr overall survival (OS) using log rank, Kaplan Meier and Cox regression. Results: Among 112 pts in Cohort A, median pt age was 51yrs (21-77), median primary tumor size 3.2cm (0.8-15cm), median follow-up 54 mos (range 34-78). Subtypes were ER+HER2-, 71 (63%); ER+HER2+, 24 (21%); ER-HER2+, 9 (8%); ER-HER2-, 8 (7%). 3yr OS was 70% (95%CI, 63-79)...