RETINOBLASTOMA

A malignant eye tumor caused by the loss of a pair of tumor-suppressor genes. An inherited form of retinoblastoma (it typically appears at birth, leads to multiple tumors and affects both eyes) is due to a transmissible (germline) mutation followed by an acquired (somatic) mutation. The sporadic form of retinoblastoma (it has later onset and leads to a single tumor in one eye) is due to acquired (somatic) mutations of both tumor-suppressor genes. When the tumor is detected at an early stage, it can sometimes be treated locally, but it oftren unfortunately requires removal of the eye (enucleation).