Postmastectomy Radiotherapy In Breast Cancerpatients With T1‐2and One To Three Positive Lymph Nodes: A Meta‐analysis

Introduction: This analysis intends to collect all the relevantclinical studies that used evidence-based medicine methods, and reviewthe research data, for a comprehensive evaluation of postmastectomyradiotherapy (PMRT) for influencing the prognosis of T1-2N1breast cancerpatients.Method: A systematic search was performed in MEDLINE (OVID), PubMed,Embase, CBM, CNKI, VIP, and Wan Fang databases of studies published fromJanuary1995to August2013to evaluate the comparison of clinical outcomeof breast cancer patients with T1-2N1with or without postmastectomyradiotherapy. Inclusion criteria required a PMRT group compared with ano PMRT group. Meta-regression (random effects logistic modeling) wasused to obtain summary estimates of sensitivity and specificity.Result: Twelve studies with locoregional recurrence-free survival(LRFS) data were included, with evaluation of4，747T1-2N1patients. Therewere significant differences between the no-PMRT and PMRT groups in5-yearLRFS with a Relative Risk (RR) of0.947(95%CI0.927to0.968， p<0.001)and in10-year LRFS with a RR of0.897(95%CI0.851to0.946， p<0.001).Eight studies were available with disease-free survival (DFS) data andnine studies were available with overall survival (OS) data. There wasa5-year DFS with a RR of0.917(95%CI0.874to0.963, p<0.001) and the10-year DFS with a RR of0.859(95%CI0.780to0.947, p=0.002). Ten studieswere available with OS data, and the5-year OS with a RR of0.942(95%CI0.911to0.975, p=0.001) and the10-year OS with a RR of0.927(95%CI0.868to0.990, p=0.024).Conclusion: For T1-T2breast cancer patients with one to threepositive lymph nodes, PMRT should be considered.