Dryja TP, et al. - Researchers investigated complement proteins in the retina of an eye affected by cancer-associated retinopathy (CAR), which represents a paraneoplastic syndrome typically related to autoantibodies against cancer antigens that cross-react with antigens in the retina. In these cases, antirecoverin has been identified as the most convincingly implicated retinal autoantibody. Likely, photoreceptor cells are destroyed by autoantibodies via the classical complement pathway. There is no published data reporting an assessment of the complement pathway in patients with CAR.