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Vitreoretinal lymphoma: a 20-year review of incidence, clinical and cytologic features, treatment, and outcomes.

OBJECTIVES
To determine the incidence and clinical and cytologic diagnostic accuracy of vitreoretinal lymphoma (VRL) and to evaluate its clinical features, management, and outcomes in a cohort of patients who underwent diagnostic vitrectomy.


METHODS
Retrospective medical record review of 463 diagnostic vitrectomy specimens from 430 patients collected from October 1, 1990, through December 31, 2010, from Vancouver General Hospital and the British Columbia Cancer Agency.


RESULTS
A total of 22 patients were diagnosed as having VRL with a preoperative clinical diagnostic sensitivity of 77%, specificity of 73%, positive predictive value of 13%, and negative predictive value of 98%. The cytologic diagnostic sensitivity was 87% (27 of 31 specimens). The incidence of VRL in British Columbia doubled from 1990 to 2010, with a final incidence of 0.047 cases per 100 000 people per year. The mean age at diagnosis was 66 years. Seventeen patients (77%) were women. The initial diagnosis of lymphoma was VRL in 19 patients (86%), of whom 7 (37%) had concurrent central nervous system lymphoma. Recurrent disease was found in 11 patients. Large B-cell lymphoma was diagnosed in 20 patients (91%). The median progression-free survival was 11 months, and the median survival was 33 months from the initial diagnosis.


CONCLUSIONS
Vitreoretinal lymphoma remains a clinical diagnostic challenge. Early clinical suspicion with subsequent diagnostic vitrectomy for cytologic analysis and collaboration with the oncology department is critical to appropriate and prompt staging and treatment. More interdisciplinary studies are required to further characterize VRL and maximize the therapeutic options, thus improving the morbidity and mortality associated with the disease.