Retinoblastoma
Retinoblastoma is a cancer of the retina. It mostly occurs in younger children and accounts for about 3% of the cancers occurring in children younger than 15 years. The estimated annual incidence is approximately 4 per million children.
The tumor may be in one eye only or in both eyes. Retinoblastoma is usually confined to the eye and does not spread to nearby tissue or other parts of the body. The patient's choice of treatment depend on the extent of the disease within and beyond the eye.
Retinoblastoma may be hereditary (inherited) or nonhereditary. The hereditary form may be in one or both eyes, and generally affects younger children. Most retinoblastoma occurring in only one eye is not hereditary and is more often found in older children. When the disease occurs in both eyes, it is always hereditary. Because of the hereditary factor, patients and their brothers and sisters should have periodic examinations, including genetic counseling, to determine their risk for developing the disease.
A statistical study by Alfred E. Knudson, led to a hypothesis about why some retinablastomas are hereditary and others occur by chance. This hypothesis led to the first identification of a tumor suppressor gene. Knudson won the 1998 Albert Lasker Medical Research Award for this work.
