Retinoblastoma is an incredibly rare type of eye cancer that begins at the retina. The retina is the very back part of the eyeball and is responsible for communicating between the eyes and the brain.
Retinoblastoma most commonly affects children under 3, but rarely adults develop the cancer. In history, only 23 cases of retinoblastoma in adults have ever been recorded.
Retinoblastoma is referred to as hereditary but is actually caused by a gene mutation that occurs during gestation. The most common cause of retinoblastoma cancer is a mutation in the RB1 gene. This is a recessive gene, meaning it is unlikely to be caused by a parent being a carrier.
In many cases, retinoblastoma develops with the eye, which is why it mostly affects children. Hereditary retinoblastoma also usually appears in both eyes.
In other cases, the cells can randomly continue to replicate instead of regenerating at our usual pace. That is usually the cause of retinoblastoma in adults.
Symptoms that suggest you might have retinoblastoma include: lazy eye, vision problems, swollen or sore eye, redness in the eye, a milky white pupil in reaction to light.
An often unintentional method of detecting retinoblastoma is using flash photography. Where healthy eyes turn red under the light of a flash camera, an eye with retinoblastoma will appear milky white color. Doctor’s will shine a light in the eye to test for the cancer in the same way.
If, you notice any of the above symptoms, make an appointment with your doctor immediately. If they think you or your child might have retinoblastoma, they will send you for further testing.
To determine symptoms in very small children, your doctor might conduct electroretinography in place of a vision test. This measures activity in the brain without relying on feedback from the patient themselves.
A special eye exam called an ophthalmic examination is the first method of detecting retinoblastoma. It is done under general anesthetic and involves a doctor inspecting a live, blown-up image of the retina.
If an ophthalmic examination confirms the presence of retinoblastoma cancer, an MRI or ultrasound will be conducted to confirm it. These scans can also determine whether the cancer has spread to other areas of the eye or head.
Genetic testing can be done to determine the chance of passing on the RB1 gene or to detect retinoblastoma in babies shortly after birth.
The 5-year survival rate for children with retinoblastoma is 96%, which is very promising. As with any cancer, the chance of survival is highest if the cancer is caught early. This decreases with time, as the cancer has a chance to spread to other areas of the body, such as the brain.
Retinoblastoma prognosis in adults cannot be estimated because it is so rare. Studies vary in estimates of vision prognosis, but many have found that vision returns in over 50% of survivors.
Established treatments for retinoblastoma include cryotherapy, thermotherapy, chemotherapy, radiation therapy, stem cell rescue or surgery.
Cryo- and thermotherapy involve using extreme cold or heat to destroy problematic cells. This is done using probes or lasers.
Chemotherapy is the best-known cancer treatment and involves using drugs to kills cancer cells. Chemotherapy kills healthy cells as well as cancerous ones, so stem cells are sometimes introduced to replace the destroyed healthy cells.
Radiation therapy uses radiation (from x-rays) to kill cancer cells.
If there is no chance that vision will be saved, surgery to remove the eye will be conducted. This surgery will allow a pathologist to determine whether the cancer has spread or is likely to spread in the future.