Purpose:
Primary vitreoretinal lymphoma (PVRL) is a non-Hodgkin B-cell lymphoma with a median survival of less than 5 years, due to frequent involvement of the central nervous system (CNS). Rituximab is a monoclonal antibody targeted against CD20, which is found on the B cell surface in over 90% of PVRL cases. Following up on a pilot study (2011 ARVO Abstract 1623), we sought to describe the effectiveness and safety of intravitreal rituximab in treating a large group of patients with PVRL.
Methods:
Cases were identified by web-based survey of the American Uveitis Society. Clinical data were collected using a standardized questionnaire, including demographics, method of diagnosis and clinical characteristics, local and CNS-directed treatments, therapeutic response, morbidity and mortality.
Results:
48 eyes of 33 patients (M:F = 1: 1.2, mean age = 61 years, range = 32 - 86 years; 91% Caucasian) qualified. Initial site was CNS in 42% and eye in 58% of patients. In all cases, intravitreal rituximab dose was 1 mg/0.1 mL, but dosing intervals varied widely and up to 2-monthly. Eyes received an average of 4.9 injections (range = 1 - 17 injections) over a mean time period of 4.1 months (range = 0 - 18 months). Some eyes were also treated with intravitreal methotrexate (65%), systemic chemotherapy (60%), whole brain irradiation (6%), and ocular irradiation (2%); 7 eyes received no treatment other than intravitreal rituximab. Remission was complete in 60% and partial in 19% of injected eyes. Of 29 eyes that experienced full remission, 35% were treated with local chemotherapy alone (i.e., intravitreal rituximab ± methotrexate). Nine eyes achieved partial remission, and 44% of these were treated with local chemotherapy alone. Among the eyes that showed full remission, 81% maintained remission, whereas 19% relapsed after a mean of 12.3 months. Visual acuity was > 20/50 in 46% and ≤ 20/200 in 26% of eyes at presentation, and > 20/50 in 59% and ≤ 20/200 in 22% of eyes following treatment. Adverse events documented during treatment in 20% of eyes included keratopathy, granulomatous anterior uveitis, cataract, maculopathy and retinal detachment. However, of the 10 eyes with reported complications, 7 were not attributed to rituximab, and the remaining 3 were possibly related to the medication and/or injection procedure. Over the course of follow-up (mean = 12.8 months, range = 0.5 - 36 months), CNS involvement was reported in 73% of patients. Of the 33 patients, 25 are living and 8 are deceased.
Conclusions:
In patients with PVRL, intravitreal rituximab is a promising treatment option that appears to be well-tolerated. A multi-center randomized controlled clinical trial would be an appropriate next step to thoroughly evaluate the role for this therapy.