Quality of Life After Locoregional Treatment in Women with De Novo Metastatic Breast Cancer: A Systematic Review and Meta-Analysis

Introduction: Primary site locoregional treatment (LRT) of metastatic breast cancer has been performed and evaluated with the aim to improve survival, prevent complications, and alleviate local symptoms. As some studies fail to show a survival benefit, the quality of life is important to consider when deciding on LRT. The aim of this study was to evaluate and quantify the impact of LRT on the quality of life of patients with de novo metastatic breast cancer (dnMBC) through a systematic review of the literature and a meta-analysis. Methods: Multiple databases were searched on May 2024 with the following keywords: (i) dnMBC; (ii) LRT, including surgery +/- radiotherapy; and (iii) QOL. Results: Six studies were included in the qualitative synthesis and four in meta-analysis (481 women, n = 251 in the LRT and n = 230 in the control groups). There was a significant QOL decrease in the LRT group at 18 months (standardized mean difference [SMD] = -0.63; 95% confidence interval [CI] -0.98--0.26; p < 0.001, low heterogeneity I2 = 33%) and after 30 months (SMD -0.82; 95%CI -1.58--0.06; p = 0.034, high heterogeneity I2 = 93%), while no statistically significant difference was observed at short term (6 months, p = 0.333). Conclusions: This study shows that there is lacking evidence regarding the QOL benefits after LRT in this population, and even a numerical deterioration in global QOL several months after the treatment. Future and ongoing research may provide additional insights into this question on dnMBC and specifics subgroups.