De novo metastatic breast cancer (dnMBC) represents 6–10% of breast cancer. Due to its incurability, dnMBC is generally treated with systemic therapies to achieve disease control and reduce tumor-related symptoms. The need for radical loco-regional treatment and its consequent benefit in this setting remains still controversial. Meta-analysis of retrospective studies and prospective randomized studies did not report a clear survival benefit. The aim of this study was to analyze the impact of surgery to primary tumor (PT) in patients (pts) presenting with dnMBC.
Between Feb 2006-Oct 2015 we performed a retrospective chart review to 129 consecutive pts who attended our hospital with dnMBC. Descriptive, Kaplan-Meier and Cox regression analyses were carried out using SPSS version 23.0.
A total of 129 pts. were analyzed. Median age was 68 years (range: 20-95), 59 pts (46%) had single organ metastasis, and their distribution according to the predominant site of disease was: skin/soft tissue 42 pts (33%), bone 87 pts (67%) and visceral 85 pts (66%). Surgery (S) of the PT was done in 32 pts (25%), 24 was radical procedures, 8 palliative and besides, 27 pts underwent axillary dissection. Initial S treatment was the choice for 29 pts. In the S group single organ disease was present in 66% vs 39% non-S group. Metastatic sites were: 50% vs 71% visceral, 44% vs 21% with bone metastasis in the S vs non-S group respectively. With a median follow-up of 2 years (SD 2.20), the 5-yr overall survival (OS) was 11.64% in the entire de novo MBC population, with a median OS of 36 m in the S-group vs 21 m. in the non-S-group (HR 1.46 p = 0.081). Subgroup analyses did not show a benefit of PT surgery in OS regardless of the number of metastasis and site of disease, and BC subtypes. The multi-adjusted HR for surgery was 0.14 (p = 0.188). The multivariate Cox regression analysis model included the site of disease (p = 0.971), the histopathologic grade (p = 0.876) and the hormone receptor status (p = 0.003).
In our series, surgical treatment of the primary tumor in patients with de novo metastatic breast cancer did not show a benefit in overall survival. Results of ongoing randomized trials are needed.
Clinical trial identification
Legal entity responsible for the study
Medical Oncology Service, Basurto University Hospital.
Has not received any funding.
All authors have declared no conflicts of interest.