Stage IV breast cancer in the community hospital setting: Primary tumor extirpation effect on overall survival.
90 Background: Publications from academic centers and national cancer databases suggest a survival advantage for women who undergo primary tumor extirpation in the setting of known distant disease. We asked if similar findings exist in a community hospital setting. Methods: 15,887 patients entered in a longitudinally maintained breast cancer database (encompassing a system network of 13 community hospitals) during 1985-2009 were analyzed for those diagnosed with stage IV disease upon initial presentation. The cohort was divided into those who underwent primary tumor resection, and those who did not. The two subgroups were compared for patient demographics, tumor characteristics, sites of distant metastases, systemic treatment, and overall survival (OS). Results: 643 (4.05%) presented with an intact primary breast malignancy and synchronous distant metastasis. Median age at diagnosis: 66 years (range 22-96). Median OS: 15 months (range 0-249). 264 (41.1%) patients underwent primary tumor resection as part of first course treatment. On Kaplan-Meier univariate analysis, patients who underwent surgical extirpation of the primary tumor demonstrated improved median OS compared to those who did not (26 vs 10 months; p<0.0001, HR 0.52). Age at diagnosis <50 (p=0.0003, HR 0.65) and oligometastasis to bone (p=0.0002, HR 0.72) were statistically significant predictors of improved OS. Race, primary tumor size, and ER status alone did not influence OS. Those ER+ patients who underwent primary tumor excision in addition to chemotherapy and/or hormonal therapy fared significantly better than those treated with systemic therapy alone (32 vs 17 months; p<0.0001). Chemotherapy 16+ weeks prior to surgery improved OS compared to those who had surgery <16 weeks after starting chemotherapy. While there was no difference with regards to type of resection (partial vs simple vs modified radical mastectomy), clear margins were imperative to optimize OS. Conclusions: Patients with stage IV breast cancer treated at community hospitals also demonstrate improved OS after primary tumor extirpation, especially in the context of a multimodality approach combining chemotherapy and/or hormonal therapy preceding surgery.