Primary Vitreoretinal Lymphoma Masquerading as Refractory Uveitis—Just Go with the Flow

Primary vitreoretinal lymphoma (PVRL) is a rare and often misdiagnosed malignant neoplasm that can mimic uveitis, leading to diagnostic challenges. In this case, a 59-year-old man initially presented with symptoms suggestive of intermediate uveitis, which responded to steroid treatment but relapsed upon discontinuation. A vitrectomy and flow cytometry confirmed the diagnosis of B-cell lymphoma. The patient underwent systemic chemotherapy, resulting in remission with no evidence of disease after 24 months. Early and accurate diagnosis is crucial to prevent CNS progression, which is a major cause of mortality. Flow cytometry is highlighted as a valuable diagnostic tool, and systemic chemotherapy is recommended for optimal outcomes.