Clinical outcomes of intravitreal methotrexate injection protocol with a reduced initial frequency for intraocular lymphoma.

Background/purpose: To investigate the clinical characteristics of intraocular lymphoma and to evaluate two protocols of intravitreal methotrexate injection.

Methods: A retrospective chart review was conducted of newly-diagnosed intraocular lymphoma patients between January 2013 and January 2018 at National Taiwan University Hospital. Patients were divided into two groups. In Group A, intravitreal methotrexate was administered weekly for the initial 8 weeks, every 2 weeks for the following 12 weeks, and then monthly for 7 months. In Group B, intravitreal methotrexate was administered twice a week for the initial 2 weeks, weekly for the subsequent 2 weeks, once every 2 weeks for the next 1 month, and monthly for the last 10 months.

Results: A total of 12 patients were analyzed in the study; seven of these patients were allocated to Group A. Differences in the overall survival and progression-free survival between the two groups did not yield statistical significance. The median visual acuity was improved from LogMAR 0.46 to LogMAR 0.30 with borderline significance in Group A (p = 0.053). Two of seven patients in Group A and five of five patients in Group B developed punctate keratitis during intravitreal methotrexate injection treatment.

Conclusion: Intravitreal methotrexate is an effective and repeatable treatment for intraocular lymphoma. A new protocol with reduced frequency of intravitreal injections as shown in this study could potentially produce similar results without a worse prognosis, along with a decrease in the incidence of keratitis.