MedGen

The absence of staining for estrogen receptor, progesterone receptor, and hormone epidermal growth factor receptor 2 (HER2/neu). [from SNOMEDCT_US]

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]

Retinoblastoma is a malignant tumor of the developing retina that occurs in children, usually before age five years. Retinoblastoma develops from cells that have cancer-predisposing variants in both copies of RB1. Retinoblastoma may be unifocal or multifocal. About 60% of affected individuals have unilateral retinoblastoma with a mean age of diagnosis of 24 months; about 40% have bilateral retinoblastoma with a mean age of diagnosis of 15 months. Heritable retinoblastoma is an autosomal dominant susceptibility for retinoblastoma. Individuals with heritable retinoblastoma are also at increased risk of developing non-ocular tumors. [from GeneReviews]