Abstract
BACKGROUND: This study aimed to determine the national incidence, characterize clinical features, and evaluate the treatment outcomes of primary vitreoretinal lymphoma (PVRL) in Slovenia. METHODS: We conducted a population-based, retrospective case series of all patients diagnosed with PVRL at the Eye Hospital, University Medical Center Ljubljana, between January 2013 and May 2024. The diagnosis was histopathologically confirmed, and primary central nervous system involvement was excluded. Clinical presentation, diagnostic delay, treatment modality, and adverse events were analyzed. Progression-free survival (PFS), overall survival (OS), and lymphoma-specific survival (LSS) were calculated. RESULTS: Twelve patients were diagnosed with PVRL (four men, eight women; median age of 76 years). The average annual incidence was 0.52 cases per million. The median time from symptom onset to diagnosis was 238 days. The two most common symptoms were decreased visual acuity (75%) and floaters (58%). Vitreous cellular infiltration was the predominant clinical sign and was observed in 92% of patients. Five patients presented with unilateral disease, seven with bilateral disease, and three with unilateral disease that progressed to bilateral involvement. The median follow-up was 31.5 months. Eleven patients received one or more treatment modalities: intravitreal rituximab and/or methotrexate, local radiotherapy, and/or systemic chemotherapy. Local remission was achieved in all treated eyes. Two cases of granulomatous uveitis occurred during intravitreal rituximab therapy. The median PFS was 12 months; the two- and three-year PFS rates were 37.5% and 18.8%, respectively. The median OS was not reached; the two- and three-year OS rates were 70% and 56%, respectively. The LSS was 80% at two years and 64% at three years. CONCLUSIONS: This Slovenian population-based study provides real-world insights into PVRL management. In elderly and medically fragile patients, local treatment modalities provided effective ocular disease control with acceptable toxicity.