Background: Bilateral diffuse uveal melanocytic proliferation (BDUMP) is a paraneoplastic ocular syndrome occurring in patients with systemic, often occult but advanced carcinoma and is the hallmark of poor prognosis. Ocular signs precede manifestation of systemic carcinoma by 3-12 months, highlighting the need for appropriate index of suspicion and prompt evaluation. Treatment options for BDUMP are limited. Investigations are aimed at finding the occult primary malignancy, which can be challenging. Modalities for treatment of the ocular findings include corticosteroids, surgery, external beam radiotherapy, and treatment of the underlying malignant neoplasm. However, it is uncertain whether earlier intervention for the systemic malignancy will impact survival, as this paraneoplastic phenomenon is thought to occur in advanced malignancy.
Case presentation: We report a unique rare atypical case with BDUMP causing visual loss in a 62-year-old female as the presenting sign of central nervous system (CNS) B-cell lymphoma. Multiple grey or grey brown subretinal lesions with pigment clumps were present in both eyes on fundoscopy and multimodal imaging demonstrated multiple discrete lesions at the level of retinal pigment epithelium. Neuroimaging revealed presence of brainstem and cerebellopontine lesions suggestive of CNS lymphoma, which was further confirmed on biopsy.
Conclusion: In the current atypical case, prompt diagnosis and immediate referral was key, with detailed systemic evaluation by an internist and oncologist. The reported case is distinct for the reason that BDUMP occurred secondary to primary CNS lymphoma, a hitherto unreported association.