Cutaneous melanoma associated retinopathy (MAR)

Abstract

In a number of paraneoplastic syndromes, patients develop autoantibodies to tumor cells that are also reactive with normal host tissues, including neurons of the central and peripheral nervous system.1 Two forms of paraneoplastic retinopathy are now recognized: cancer-associated retinopathy (CAR),2,3 and cutaneous malignant melanoma-associated retinopathy (MAR).4–7 CAR occurs in a small percentage of patients having small cell carcinoma of the lung and other cancers, and the patients are thought to develop autoantibodies against a tumor cell antigen that cross react with their retinal rods and cones. It was recently demonstrated that sera of some CAR patients contain antibodies that react with recoverin, a calcium-binding protein found in photoreceptors and some types of cone bipolar cells.8–10 These antibodies may cross the blood retinal barrier and interfere with normal photoreceptor function. In CAR, the patient’s visual symptoms may precede or occur at about the time of tumor identification; loss of vision typically occurs over weeks to months. There is clinical, electroretinographic (ERG) and histopathologic evidence of progressive dysfunction and death of rod and cone photoreceptors in this form of retinopathy.2,3