Comparison of Survival Outcomes between Early Breast Cancer Patients who Underwent Mastectomy and Patients Treated by Breast Conserving Therapy: A Meta Analysis

BACKGROUND: Early stage of breast cancer requires mastectomy or breast conserving therapy. However, there are disagreements regarding the outcome of these two types of therapies in term of overall survivals. OBJECTIVES: The first aim of this meta-analysis was to assess the overall survival between patients who underwent mastectomy and those treated by breast conserving therapy. The second was to evaluate the influence of the follow up period on overall survival between the patients who benefited mastectomy and those who under went breast conservative therapy. METHODS: We systematically searched on PubMed and Cochrane library all published randomized trials comparing mastectomy with breast conserving therapy and assessing overall survival. RESULTS: Using dichotomous data, there was not a significant difference between mastectomy and BCT (OR:0.99; 95% CI:0.93-1.06; P:0.86). This was the same in subgroup analysis based on period of follow up. Their ORs and CI were (OR:0.97; 95% CI:0.81-1.18; P:0.79), (OR:1.01; 95% CI:0.90-1.13; P:0.87) and (OR:1.04; 95% CI:0.93-1.16; P:0.46) respectively for up to 5 years or less, between 5 and 10 years and more than 10 years of follow up. Using generic inverse variance, there was no significant difference between mastectomy and BCT, (HR:1.01; 95% CI:0.98-1.04; P:0.71). In subgroup analysis based on period of follow up, there was no significant difference between mastectomy and BCT. Their HRs, CI and P-value were (HR:1.01; 95% CI:0.951-1.07; P:0.79), (HR:0.98; 95% CI:0.92-1.04; P:0.51) and (HR:1.02; 95% CI:0.97-1.07; P:0.40) respectively for up to 5 years or less, between 5 and 10 years and more than 10 years of follow up. CONCLUSION: This meta-analysis demonstrated that there was no significant difference between patients with early stage breast cancer when they are treated by mastectomy or breast consevative therapy in term of overall survival. Additionnally, the follow up period had no any influence on the both types of surgery in term of overall survival. Therefore, we suggest that breast conservative therapy or mastectomy should be discussed between the care team and the patient, taking into account the financial means available to the patient, especially in low-income countries, the benefits of the surgery and the patient's choices.