Cone Dysfunction as a Paraneoplastic Syndrome Associated with Retinal Antigens Approximating 40 kiloDalton

Reports on cancer-associated retinopathies (CAR) have increased in recent years as the autoimmune reactions responsible have become better understood. The 23-kDalton autoantigen 'recoverin' was the first retinal antigen implicated in CAR, but others have since been described. We report an additional case involving an autoantigen other than recoverin, with five-year follow-up of a 50-year-old woman suffering from the CAR syndrome, with ocular abnormalities restricted to cone dysfunction. The patient had a history of laryngeal carcinoma surgically removed 18 months prior to presenting to the ophthalmologist with photophobia and decreased vision in both eyes. The patient's abnormal retinal hypersensitivity included antibody activity with two retinal antigens approximating 40 kD, located within the outer segments of the photoreceptor layer. To our knowledge, this is the first description of a cancer-associated, cone-specific dystrophy involving an abnormal amount of immunologic activity with two retinal proteins approximating 40 kD, that may prove to be isoforms of the same antigen.