Primary Extranodal Diffuse Large B-Cell Lymphoma In The Rituximab Era: A Single Center, Retrospective Analysis

Background: A large proportion of diffuse large B-cell lymphoma originates from extranodal sites. The outcomes of Chinese patients with primary extranodal diffuse large B-cell lymphoma (PE-DLBCL) have been greatly improved. Methods: Clinical features and outcomes of 197 patients newly diagnosed with PE-DLBCL from January 2015 to December 2020 were analyzed retrospectively. Results: (1) Gastrointestinal tract (34%) involvement ranked first, followed by central nervous system (CNS) and intraocular (31.5%), nose/nasopharynx (7.1%), breast (5.1%), testis (3.6%) and others. (2) The 3-year overall survival (OS) rate for the entire group was 81%; The 3-year OS rate of PE-DLBCL with CNS and vitreoretinal involvement was 79%. (3) In univariate analysis of PE-DLBCL, Ann Arbor stage, evaluated LDH, IPI>2 and complete remission (CR) were significantly related to survival. The lack of CR was the only independent adverse prognostic factor in OS ( p = 0.000; HR = 4.659). (4) Lugano stage and treatment response were independent prognostic factors for primary gastrointestinal DLBCL. Conclusion: This is a single-center report of PE-DLBCL in China in the past 5 years with a fairly excellent outcome and a large scale. The treatment response of patients is significantly better than before, especially in patients with CNS and vitreoretinal involvement.