Application of Orelabrutinib With or Without CD20 Monoclonal Antibody in Previously Untreated Marginal Zone Lymphoma

This study focuses on treatment-naïve marginal zone lymphoma (MZL) patients and aims to investigate the efficacy and safety of orelabrutinib combined with or without CD20 monoclonal antibody. This is a single-arm study without a control group. All subjects will receive orelabrutinib treatment but will be stratified based on disease stage and clinical characteristics into the following two groups: 1. Stage I MZL Patient Group (Monotherapy Group) Treatment regimen: Orelabrutinib monotherapy. Dosage and administration: Orelabrutinib 150mg, once daily (qd), taken continuously for 21 days per treatment cycle (d1-d21), for a total of 6 cycles (C1-C6). Target population: Patients with Ann Arbor Stage I gastric MALT MZL, including H. pylori-negative patients or those with unsatisfactory response after anti-H. pylori therapy, as well as other Stage I MZL patients unsuitable for local radiotherapy. Sample size: 50 cases. 2. Stage II-IV MZL Patient Group (Combination Therapy Group) Treatment regimen: Orelabrutinib combined with a CD20 monoclonal antibody. Dosage and administration: Orelabrutinib 150mg, once daily (qd), taken continuously for 21 days per treatment cycle (d1-d21), for a total of 6 cycles (C1-C6). CD20 monoclonal antibody (either Rituximab 375mg/m², intravenous infusion, Day 1 of each cycle, C1-C6; or Obinutuzumab 1000mg, intravenous infusion, on Days 1, 8, and 15 of Cycle 1 \[C1\], and on Day 1 of Cycles 2-6 \[C2-C6\]). Target population: Patients with Ann Arbor Stage II-IV non-gastric MALT MZL, nodal MZL, splenic marginal zone lymphoma (SMZL), and other Stage II-IV MZL patients unsuitable for local radiotherapy. Sample size: 38 cases.