- Paraneoplastic retinopathy - causes
- Paraneoplastic retinopathy - symptoms
- Paraneoplastic retinopathy - diagnosis
- Paraneoplastic retinopathy - treatment
Paraneoplastic retinopathy is an eye disease that leads to progressive loss of vision that coexists with cancer, ie, it may occur in some patients with certain types of cancer. It is most often diagnosed in patients struggling with small cell lung cancer. What are the exact causes and symptoms of paraneoplastic retinopathy? What is the treatment?
Paraneoplastic retinopathy , or cancer-associated retinopathy (CAR), belongs to the group of neurological paraneoplastic syndromes - a group of neurological diseases that arise as a result of neoplasm, however, they are not caused by its local action (infiltration, pressure) or its metastases to the nervous system.The CARsyndrome is most often found in patients with small cell lung cancer. Other cancers that appear in people with paraneoplastic retinopathy include breast cancer, ovarian and uterine cancer, thymoma, gastric cancer, Hodgkin's lymphoma, liver cell cancer, and teratomas.
Paraneoplastic retinopathy - causes
A major role in the development of the disease is played by a cross-reaction between retinal antigens (mainly a protein called recoverin) and antibodies directed against them. Recoverin is a component of suppositories and rods - the parts of the eye that are responsible for proper vision. Rekowerin plays a key role in adaptation to light and dark.
Expression of recoverin by neoplastic tissues stimulates the production of onconeuronal - anti-recoverin antibodies (these are the most common anti-retinal antibodies in CAR syndrome, although many others are also present). These antibodies cross the blood-retinal barrier to reach the photosensitive cell layer, and then initiate the death of the retinal photoreceptor cells.
Paraneoplastic retinopathy - symptoms
Paraneoplastic retinopathy symptomsmay appear before cancer is detected, but CAR symptoms have also been reported as a consequence of the primary malignant process. Thesymptoms of paraneoplastic retinopathyinclude:
- photophobia (photosensitivity)
- flickering sensationlights
- ring-shaped scotomas in the field of view
- quick and painless reduction of visual acuity in both eyes
- feeling of seeing through the fog
- twilight blindness
- color vision disorder.
Paraneoplastic retinopathy - diagnosis
In the case of the above-mentioned ailments, basic ophthalmic examinations are performed, such as Goldman perimetry (visual field examination), fundus examination in a slit lamp and fluorescein angiography. With paraneoplastic retinopathy, narrowing of the fundus arteries and sometimes changes in the retinal pigment epithelium are observed. In addition, it is visible: paling of the optic nerve and a mild inflammatory reaction in the vitreous.
An electroretinogram (ERG) is also performed, which shows a progressive dysfunction of photoreceptor cells as manifested by a decrease in the responses of rods and cones. If CAR is suspected, blood tests are also required to assess the presence of anti-recoverin antibodies in the serum.
Paraneoplastic retinopathy - treatment
The therapy includes the treatment of the tumor, as well as the administration of steroids, plasmapheresis (a procedure of purifying the blood of undesirable elements - in this case, antibodies against recoverin) and intravenous infusions of immunoglobulins. However, the last three treatments show little effect. Research is underway on the effectiveness of calcium channel blockers and monoclonal antibodies.