Cancer-associated retinopathy - A review article with some clinical examples

Cancer-associated retinopathy (CAR) is a rare paraneoplastic syndrome. In t his survey we report about two further patients with CAR, who were referred to the University Eye Hospital of Tuebingen within a few months. The most common primary tumor associated with CAR is small cell carcinoma of the lun g. Case reports about rhabdomyosarcoma, carcinoma of the endometrium, prost ate and mamma were also described. The exact pathogenesis of CAR is still u nknown. Specific autoantibodies were found against the photoreceptor protei n recoverin (23-kd retinal CAR antigen). However, this reaction is not pres ent in all patients, and probably other antigens are also involved. Most of the patients experience symptoms of CAR before the primary tumor is detect ed. Besides glare sensitivity and flashing lights, a rapidly progressive, o ften asymmetric visual loss may occur. Although paracentral and midperipher al scotomas can be found frequently, visual field defects are often quite h eterogeneous. Typically, the responses in the electroretinogram (ERG) are m arkedly reduced, but normal ERGs were also described. The fundus picture in CAR shows sheathing of the retinal vessels, narrowing of the arterioles an d crumbing of the retinal pigment epithelium. The prognosis is poor. Freque ntly there is progression to bilateral loss of vision within a few months. Treatment of the primary tumor does not seem to alter the ocular prognosis. Systemic corticosteroids may be helpful in some patients. Nevertheless, no proven therapeutic regimen is currently available.