What It Is: Retinoblastoma is a rare, cancerous tumor that develops in the retina, the light-sensitive lining on the inside of your eye. A genetic mutation causes a build-up of cell tissue which can develop into the tumor. Retinoblastoma usually occurs in only one eye, but can occur in both. It can be treated in variety of different ways — including chemotherapy, radiation therapy or surgery — depending on the size and location of the tumor.
Signs & Symptoms: Retinoblastoma causes a visible whiteness in the pupil called "cat's eye reflex," or leukocoria. This unusual whiteness is particularly noticeable when bright light shines into the eye. Other signs include eye pain, redness or irritation, blindness or poor vision in the affected eye or crossed eyes.
Who’s at Risk: Retinoblastoma tends to run in the family: 40 percent of people with retinoblastoma inherited the condition, though doctors still aren’t sure what causes the genetic mutation. Retinoblastoma is most common in children, and is usually diagnosed by age 2.