An inherited malignant tumor that originates in the nuclear layer of the retina. A predisposition to retinoblastoma has been associated with 13q14 cytogenetic abnormalities affecting the RB1 gene. Patients with the inherited form appear to be at increased risk for secondary non-ocular malignancies such as osteosarcoma, malignant fibrous histiocytoma, and fibrosarcoma. [from
NCI]