The Treatment of Ocular Adnexal Extranodal Marginal Zone B-cell Lymphoma by Orelabrutinib and Radiotherapy

Extranodal marginal zone B-cell lymphoma (EMZL) is the most common lymphoma of the ocular adnexa (OA), accounting for approximately 60%. As a special part of the body, there is no consensus on the optimal treatment strategy for OA-EMZL. Studies have shown that patients who wait for postoperative observation have a 5-year PFS of approximately 80% and a 10-year PFS of 63%. Therefore, radiotherapy remains an important treatment for stage I/II OA-EMZL patients, but the dosage of radiotherapy remains controversial. In 2014, Hoskin PJ et al. found that the complete response rate and effective rate of patients in the standard 24Gy radiation dose group were 71% and 91%, while those in the 4Gy radiation dose group were 55% and 87%, respectively. Meanwhile, the PFS of patients with 4Gy radiation dose was lower than that of the group with 24Gy radiation dose, but there was no significant difference in OS between the two groups. However, in a study conducted by Chelius M et al. in 2021, they found that the incidence of both early and late toxic effects was significantly higher in the\>4Gy radiation dose group than in the\<4Gy radiation dose group. These toxic effects inevitably affect the quality of life of patients. Therefore, investigators plan to adopt a combination of ultra-low dose radiotherapy and drug therapy, which not only reduces the side effects of radiotherapy, but also improves the complete response rate of treatment and reduces disease progression or recurrence. However, studies have shown that radiotherapy combined with rituximab cannot improve the disease-specific survival rate of OA-EMZL. Therefore, BTK inhibitors (BTKi), as a novel targeted drug for the treatment of EMZL, have been used to treat relapsed and refractory EZML by interfering with BCR signals. Based on the above research, investigators plan to explore the efficacy of combination therapy with Orelabrutinib and ultra-low dose radiotherapy (4Gy) in the treatment of stage I/II OA-EMZL.