Consolidative Radiotherapy after Complete Remission following R-CHOP Immunochemotherapy in Stage III–IV Diffuse Large B-Cell Lymphoma Patients: A Systematic Review and Meta-Analysis

SIMPLE SUMMARY: The present systematic review and meta-analysis aimed to clarify the role of consolidative RT among patients with advanced-stage DLBCL who achieved complete remission after rituximab-based immunochemotherapy (R-CHOP). Six retrospective studies involving 319 individuals who underwent R-CHOP consolidative RT and 494 individuals who did not undergo consolidative RT were included. Consolidative RT was associated with superior overall survival (HR: 2.01; 95% CI: 1.30–3.12; p = 0.002) and disease-free survival (HR: 2.18; 95% CI: 1.47–3.24; p < 0.0001). These results showed that consolidative RT is superior to no RT in terms of both overall survival and disease-free survival for patients with advanced-stage DLBCL. Further investigation is warranted to determine the optimal radiation fields and the appropriate indications for consolidative RT in patients with advanced-stage DLBCL in the rituximab era. ABSTRACT: Patients with diffuse large B-cell lymphoma (DLBCL) are treated with rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). The role of consolidative radiation therapy (RT) remains unclear among patients with advanced DLBCL who achieved complete remission (CR) after R-CHOP immunochemotherapy. The current systematic review and meta-analysis aimed to clarify the role of consolidative RT among these patients. The MEDLINE, Embase, and Cochrane Library databases were searched for studies comparing RT to no RT following CR after R-CHOP immunochemotherapy in Ann Arbor stage III–IV DLBCL patients. Overall survival (OS) was the primary endpoint, and disease-free survival (DFS) was the secondary endpoint. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to assess the primary and secondary outcomes. Review Manager (version 5.4) was used to analyze the data. Six retrospective studies involving 813 patients who received R-CHOP ± consolidative RT were identified. OS was higher in the consolidative RT group, with an HR of 2.01 and a 95% CI of 1.30 to 3.12 (p = 0.002). DFS was also higher in the RT group, with an HR of 2.18 and a 95% CI of 1.47 to 3.24 (p < 0.0001). The results suggested that consolidative RT improved OS and DFS compared to no RT among advanced-stage DLBCL patients. Further research is needed to determine the optimal radiation fields and the appropriate indications for consolidative RT for advanced-stage DLBCL patients in the rituximab era.