Cancer associated retinopathy

Cancer-associated retinopathy (CAR) is a rare paraneoplastic syndrome characterized by the progressive loss of vision due to cancer-induced immune response that mistakenly targets the retina. This condition is most commonly associated with small cell lung cancer, but it can also occur in patients with other types of cancer such as breast cancer, ovarian cancer, and endometrial cancer. The immune system, in an attempt to fight the cancer, produces antibodies that cross-react with retinal antigens, leading to retinal damage.

Symptoms

The symptoms of cancer-associated retinopathy can vary but typically include sudden and progressive vision loss, photopsia (flashing lights), night blindness, and loss of peripheral vision. These symptoms can precede the diagnosis of the underlying malignancy, making CAR a potential early marker for cancer.

Diagnosis

Diagnosis of CAR involves a comprehensive eye examination, including fundus photography, fluorescein angiography, and electroretinogram (ERG) tests that assess the functional ability of the retina. Blood tests are also conducted to identify anti-retinal antibodies. A thorough medical history and physical examination are necessary to search for the underlying cancer.

Treatment

Treatment of cancer-associated retinopathy focuses on addressing the underlying malignancy and managing the retinal symptoms. Immunotherapy, such as intravenous immunoglobulins, corticosteroids, and plasmapheresis, can be used to suppress the autoimmune response against the retina. Treating the cancer can also lead to stabilization or improvement of the retinal symptoms in some cases.

Prognosis

The prognosis for patients with cancer-associated retinopathy varies and depends on the type and stage of the underlying cancer, as well as the response to treatment. Early detection and treatment of both the retinopathy and the cancer are crucial for improving outcomes.