Trilateral retinoblastoma refers to the combination of retinoblastoma (usually bilateral) and pineoblastoma. This relationship highlights the close relationship between these highly aggressive small round blue cell tumours.
It affects only a minority of patients with retinoblastoma (1.5-5%) and is almost always seen in children with bilateral retinoblastoma; in this subset of patients, the rate may be as high as 25%.
The clinical presentation, pathology and radiographic appearances are those of retinoblastomas and pineoblastomas. The pineoblastoma is usually located in the pineal gland but can on occasion be seen in the suprasellar region.
Treatment and prognosis
Prognosis is guarded even with aggressive surgery, chemotherapy and radiotherapy. CSF seeding is common, with a dismal prognosis.