PARANEOPLASTIC RETINOPATHY - A NOVEL AUTOANTIBODY REACTION ASSOCIATEDWITH SMALL-CELL LUNG-CARCINOMA

We present the case of a 74-year-old man with rapidly progressive bila teral visual loss, optic disc pallor, retinal arteriolar attenuation, and an abnormal electroretinogram with a 90% reduction in cone functio n and a 50% reduction in rod function. He was examined for a suspected cancer-associated retinopathy (CAR). Although he was found not to hav e expressed the previously reported 23-kd CAR antibody, high titers we re found of an antibody to a 60-kd retinal protein, which as yet remai ns unidentified. An initial clinical search for an underlying cancer w as unsuccessful, but 2 months later a mediastinal mass was found on ch est x-rays, and biopsy confirmed a diagnosis of small-cell lung carcin oma. Combined therapy with oral corticosteroids and plasmapheresis res ulted in a recovery of vision from counting fingers to 20/200 in the r ight eye and 20/40 to 20/25 in the left eye. Conventional chemotherape utic management of the small-cell lung carcinoma was instituted, and t he modest visual recovery was maintained. The visual improvement as we ll as lung tumor regression were accompanied by a decline in antibody titers from 1:2,000 pretreatment to 1:200 during the course of therapy . The absence of reactivity with the previously described 23-kd retina l antigen of the CAR syndrome does not exclude the diagnosis of parane oplastic retinopathy in patients fitting the clinical profile of this disease.