Complement Proteins in the Retina in Cancer-Associated Retinopathy

Abstract

Cancer-associated retinopathy (CAR) is a paraneoplastic syndrome typically associated with autoantibodies against cancer antigens that cross-react with antigens in the retina. 1 Of the retinal autoantibodies in patients with CAR, antirecoverin is the most convincingly implicated. 2,3 The autoantibodies possibly destroy photoreceptor cells through the classical complement pathway. However, to our knowledge, an evaluation of the complement pathway in patients with CAR has not been published to date. We searched for complement proteins in the retina of an affected eye.

Ocular Paraneoplastic Syndromes

“…This results in symptoms of cone dysfunction, namely, photosensitivity as well as photopsias (type of visual hallucinations seen as light flashes), prolonged glare, decreased best-corrected visual acuity (BCVA), color discrimination or disturbed color vision, and central scotomas. Rod dysfunction may include night blindness, prolonged adaptation to darkness, and peripheral or ring scotomas [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ].…”

“…Possibly, survival of RPE cells during classical complement pathway activation is due to expression of inhibitory proteins on their surface. Clearly, further research is needed [ 10 ].…”