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Cell-Free DNA Extraction of Vitreous and Aqueous Humor Specimens for Diagnosis and Monitoring of Vitreoretinal Lymphoma
Published on: January 12, 2024
Intravitreal methotrexate resistance in a patient with primary intraocular lymphoma
H Nida Sen1, Chi-Chao Chan, Gordon Byrnes
1Laboratory of Immunology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA. nidasen@gwu.edu
Purpose:
To describe the clinical course of a patient with multiple recurrences of primary intraocular lymphoma (PIOL).
Design:
Interventional case report,
Methods:
Retrospective chart review.
Results:
A 57-year-old female treated with multiple intravitreal methotrexate injections became refractory to intravitreal methotrexate after a year. Lymphoma cells evaluated using immunocytochemistry and confocal microscopy showed aberrant multidrug resistance-related protein (MRP) and decreased reduced folate carrier (RFC) and folate binding protein (FBP) expression compared to PIOL cells from another patient clinically responsive to methotrexate.
Conclusions:
This case suggests that alterations in the transport of methotrexate across the cell membrane might contribute to resistance following repeated intravitreal injections.
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