Vitreoretinal lymphoma: the importance of cerebral spinal fluid evaluation at initial diagnosis.

Background/aims: To determine if patients with vitreoretinal lymphoma (VRL) and concomitant central nervous system lymphoma (CNSL) may present without brain MRI findings, but possess cerebrospinal fluid (CSF) suspicious for lymphoma.

Methods: This was a retrospective, single-centre, observational study evaluating patients with a diagnosis or suspicion of VRL seen at Memorial Sloan Kettering Cancer Center between 2006 and 2024. Patients were included if the final diagnosis was biopsy-proven CNSL and both MRI brain with and without contrast±CSF evaluation (obligatory for inclusion if MRI negative) were performed at the initial diagnostic workup. Patients were excluded if CNS disease treatment (brain, spine or CSF) preceded ocular disease. Patients with prior extra-CNS disease were included. Clinical records and radiographic imaging were retrospectively reviewed and relevant data were recorded for each patient. We evaluated the proportion of patients with MRI negative and CSF suspicious for lymphoma. Subgroup analysis included imaging features, pathology, treatment and disease course.

Results: We identified 65 patients. Of the 65 patients at the presentation of VRL, 30 had negative MRI brain and CSF, 16 had positive brain MRI and negative CSF and 8 had both positive MRI brain and CSF. 11 (16.9%) had CSF suspicious for lymphoma without positive findings on MRI of the brain. In this subgroup, the median age was 66 years (range 49-82) and 36% were female. 86% of these patients were asymptomatic neurologically. 73% underwent systemic treatment. At a mean 3 years follow-up, 91% of patients were living.

Conclusion: In patients with suspected VRL, it is possible to have CSF test positive for lymphoma in the context of negative brain MRI. This suggests, when evaluating VRL patients for concomitant CNS disease, CSF evaluation leads to earlier detection and systemic treatment, even when MRI brain findings are negative. In our cohort, an absence of CSF evaluation in the context of negative brain MRI could have missed 16.9% of patients with CNS lymphoma.