Primary tumor extirpation in breast cancer patients who present with stage IV disease is associated with improved survival

Purpose: Previous evaluation of our institutional experience with stage IV breast cancer patients with an intact primary tumor (IPT) did not reveal an overall survival (OS) benefit for surgery at 32.1 months median follow-up. We assessed the impact of surgery after 74.2 months median follow-up, and the effect of systemic therapy and local radiotherapy (RT). Methods: We reviewed the records of all patients presenting from 1997 to 2002 with stage IV disease with an IPT. Cox proportional hazards modeling was used to assess differences in survival between treatment groups. Results: Seventy-four (35.6 %) of 208 patients underwent resection of the IPT. After adjustment for covariates, surgery was associated with improved OS (p = 0.04). Multivariable analysis revealed that estrogen receptor (ER) positivity (p = 0.002) and having only a single focus of metastatic disease (p = 0.05) were also associated with improved OS. Surgery was highly associated with receipt of RT (p = 0.0003). RT was significantly associated with improved survival (p = 0.015) in an exploratory analysis. Conclusions: Stage IV breast cancer patients with an IPT treated surgically had significantly improved OS. Radiation to the primary was also associated with improved survival, but this was evident only with adjustment for the effect of surgery. These findings may be limited by selection bias. Completion of ongoing prospective randomized trials is needed to conclusively determine whether stage IV patients with an IPT should be offered aggressive locoregional therapy.