Trilateral Retinoblastoma

**Semantic type:** Neoplastic Process

**Definition:** Trilateral retinoblastoma refers to bilateral (or less often unilateral) retinoblastoma associated with an intracranial primitive neuroectodermal tumor in the pineal or suprasellar region. This syndrome is often associated with a increased familial incidence of retinoblastoma. (From Cancer 86(1): 135-141, 1999).