Surgery improves benefit of systemic therapy for late-stage breast cancer

Locoregional surgery followed by systemic therapy may be of greater benefit for patients with stage 4 breast cancer who are treatment-naive than systemic therapy alone, according to the results of a multicenter, phase 3 trial presented at the ASCO Annual Meeting.

“Generally, we use systemic therapy in patients diagnosed with stage 4 disease,” Atilla Soran, MD, MPH, professor of surgery at the University of Pittsburgh Medical Center, told HemOnc Today. “Prospective studies and meta-analyses show that surgery may prolong survival, but there have been no randomized studies evaluating this. We initiated a randomized study comparing surgery with systemic therapy.”

Atilla Soran

Soran and colleagues compared 3-year survival and locoregional progression in 274 patients. Patients were randomly assigned to locoregional surgery followed by systemic therapy (n = 138) or systemic therapy alone (n = 136). Characteristics such as age, BMI, HER-2 status, tumor type, size and histologic grade, and bone and visceral metastases were comparable between groups (P > .05 for all). Median follow-up was 40 months (range, 20-51 months).

At 36 months, survival was similar between patients in the locoregional surgery group and the systemic therapy group (60% vs. 51%, respectively). OS was higher in the locoregional surgery group than in the systemic therapy group (HR, 0.66; 95% CI, 0.49 to 0.88). OS was statistically higher in the locoregional surgery group in unplanned subgroup analyses: ER/PR positivity (HR, 0.64; 95% CI, 0.46 to 0.91), HER-2 negativity (HR, 0.64; 95% CI, 0.45 to 0.91), age under 55 years (HR, 0.57; 95% CI, 0.38 to 0.86) and bone-only metastasis (HR, 0.47; 95% CI, 0.23 to 0.98). Median survival was 14 months longer in the locoregional surgery group compared with the systemic therapy group among patients with bone-only metastases (56 months vs. 42 months; HR, 0.67; 95% CI, 0.43 to 1.07). Locoregional progression occurred in 1% of patients (n = 2) in the locoregional surgery group and in 11% (n = 15) of patients in the systemic therapy group (P = .001).

“Patients undergoing surgery who were ER– and PR–positive, HER-2–negative and aged 55 years and under, with bone-only metastases, lived longer,” Soran told HemOnc Today. “For patients in this subgroup, we believe that surgery has a benefit.” – by Julia Ernst, MS

Reference:

Soran A, et al. Abstract 1005. Presented at: ASCO Annual Meeting; June 3-7, 2016; Chicago.

Disclosure: Soran reports no relevant financial disclosures.