Tumours in the eye usually are secondary tumours caused by cancers that have spread from other parts of the body, especially the breast, lung, bowel or prostate. Two types of primary tumors arise within the eye itself and are known as retinoblastoma in children and melanoma in adults.
Retinoblastoma is a cancer of the retina, the eye's light-sensitive tissue. This most common childhood eye cancer usually strikes children under age five, affecting 500 to 600 in the United States each year. In nearly a third of the cases, retinoblastoma occurs in both eyes. While symptoms are not evident early in the disease, increasing pain and vision loss eventually signal the problem.