Epidemiology and survival outcomes of patients with primary intraocular lymphoma: a population-based analysis

BACKGROUND: Primary intraocular lymphoma (PIOL) is a rare malignancy with a poor prognosis, but its optimal therapy remains unclear. Herein, we aimed to analyze the epidemiology and survival outcomes of PIOL patients based on a population-based cancer registry in the United States. METHODS: Patients diagnosed with PIOL between 1992 and 2018 were identified from the Surveillance Epidemiology and End Results program. The patients were divided into two groups: those aged < 60 years and ≥ 60 years. We used the chi-squared test to analyze the differences between the two groups. Descriptive analyses were performed to analyze epidemiological characteristics and treatment. The likely prognostic factors were analyzed by Kaplan–Meier curves and Cox proportional hazards models. RESULTS: The overall incidence of PIOL was 0.23/1,000,000, which was steadily increasing from 1992 to 2018, with an annual percentage change of 2.35. In total, 326 patients (mean age, 66.1 years) with PIOL were included in this study, 72.1% were aged ≥ 60 years, 84.4% were White, and 60.4% were female. The most common pathological type was diffuse large B-cell lymphoma (DLBCL), but in patients aged < 60 years, extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue was the most common. The disease-specific survival rates were 74.2% and 61.5% 5 and 10 years after diagnosis, respectively. Survival analysis found that surgery, radiation, and chemotherapy did not lead to better prognosis. CONCLUSIONS: PIOL is a rare disease with poor prognosis, and its incidence has been increasing for nearly 30 years. It usually affects people aged ≥ 60 years, and DLBCL is the most common pathological type of PIOL. Patients aged < 60 years and with non-DLBCL type have improved survival. Survival of PIOL has improved in recent years.