Evaluation of Relapse Rate and Survival Outcome of Patients with Diffuse Large B Cell Lymphoma after Consolidative Irradiation: Retrospective Study

Background: Non-Hodgkin lymphomas are the most common lymphoid neoplasms of the lymphoid system in adults, accounting for anywhere from 4% to 10% of all malignancies worldwide. Diffuse large B-cell lymphoma (DLBCL) is the most dominant histological subtype. Objective: This study aimed to assess the relapse rate and secondary endpoint, which was the survival outcome of DLBCL following consolidative irradiation. Methods: This retrospective descriptive phase II study included 105 patients with DLBCL and received consolidation radiotherapy (RT) at Clinical Oncology Department, Tanta University Hospitals. The patients underwent chemotherapy and RT. The response was evaluated through computed tomography (CT)-scan or positron emission tomography/CT scan and bone marrow in those with involved bone marrow. Results: The three-year overall survival (OS) was higher in patients with good performance status (ECOG0-1) compared to those with poor performance status (97% vs. 81% respectively). The difference was statistically significant (p = 0.015). The three-year OS was higher in patients without relapse compared to those with relapse (97% vs. 70% respectively). The difference was statistically significant (p = 0.000). The three-year OS was higher in patients with CR after consolidative RT compared to those with SD after consolidative RT (98% vs. 52% respectively). The difference was statistically significant (p = 0.000). Conclusions: Consolidative RT remains a valuable component in the management of DLBCL, particularly for patients with bulky disease and adverse prognostic factors. Its selective use alongside immunochemotherapy may contribute to improved disease control and support individualized treatment strategies.