Corneal Lymphoma in Humans: First Population-Based Evidence of Occurrence and Clinical Characteristics

Lymphomas involving ocular structures are well documented, particularly in the conjunctiva, vitreoretina, and choroid. In contrast, no primary lymphoma of the cornea has previously been reported in humans, whereas it has only been described in animals, essentially in rare, small series in horses. This study aimed to determine whether corneal lymphoma exists in humans and to describe its epidemiologic and clinical characteristics.

A retrospective, population-based analysis was conducted using the SEER 17 registries (November 2024 submission). All lymphoma cases coded as C69.1 (cornea) between 2000 and 2022 were included. Demographic, pathological, treatment, and survival data were extracted using SEER*Stat version 9.0.42.0. Incidence rates were age-adjusted to the 2000 U.S. standard population. Survival was calculated from diagnosis to death or last follow-up.

Five cases of corneal lymphoma were identified, all strictly localized to the cornea, corresponding to an incidence of 0.0028 cases per million persons per year. The mean age at diagnosis was 75 years, with a 4:1 male predominance. Histologic subtype was available in 3 cases, all of which were mucosa-associated lymphoid tissue (MALT) lymphomas. All patients underwent local surgical management, and radiotherapy was administered in unilateral cases. No systemic therapy was reported. Median follow-up was 99 months. Two deaths occurred (1 unrelated to lymphoma and 1 lymphoma-related) while 3 patients remained alive, including 2 long-term survivors with follow-up exceeding 14 years.

Corneal lymphoma does occur in humans, is exceptionally rare, and appears to share the favorable prognosis of other ocular MALT lymphomas. Radiotherapy may provide durable control in localized disease. These findings represent the first evidence of this entity and support heightened diagnostic awareness in ocular oncology.