De-novo metastatic breast cancers with or without primary tumor resection – A 10-year study

Abstract

Background : Treatment of de novo metastatic breast cancer is usually palliative with systemic treatment; surgical excision of the primary tumour is reserved in patients with significant symptoms from the primary tumour. Survival benefit of surgical removal of the primary tumour remains controversial. Methods : All patients treated with de novo metastatic breast cancer (MBC) between 2007 and 2016 were retrieved from a prospectively-maintained database. Demographic and tumour characteristics were compared. Overall survival (OS) was analysed using Kaplan-Meier Method and log rank tests. Multivariate analysis was performed to evaluate the prognosticators of OS in de novo MBC. Results : Median age of diagnosis was 53 years old (Range 24 - 91 years old). 91 patients received resection of the primary tumour, including 86 mastectomies and 5 breast conserving surgeries (surgical group). 81 patients were never treated surgically (non-surgical group). Baseline demographic data were comparable apart from being younger age in the surgical group. 5-year OS in surgical group was significantly better than non-surgical group (43.9% vs. 33.9%, p = 0.026). Multivariate analysis found that advanced age (Hazard ratio: 1.034, p = 0.005, 95% CI 1.010 – 1.058) and presence of visceral metastasis (Hazard ratio: 1.672, p = 0.038, 95% CI 1.028 – 2.719) were significant adverse prognosticators through multivariate analysis; while positive oestrogen receptor (ER) status was the only positive prognosticator in the analysis (Hazard ratio: 0.42, p = 0.001, 95% CI 0.256 – 0.688). Conclusion : Surgical excision of primary breast tumour may confer survival benefit in de novo MBC. Micro-abstract Surgical excision of primary tumor in the context of de novo metastatic breast cancer has been controversial. This is a 10-year retrospective analysis of a prospectively-maintained database on de novo metastatic breast cancer. Results of this study showed that while 5-year overall survival remains poor, surgical excision of primary breast tumor may result in a survival benefit in carefully selected patients.