Trilateral retinoblastoma: is the location of the intracranial tumor important?

BACKGROUND: Trilateral retinoblastoma refers to bilateral retinoblastoma associated with an intracranial primitive neuroectodermal tumor in the pineal or suprasellar region. The purpose of this study was to review patient and tumor characteristics and treatment outcome in patients with trilateral retinoblastoma and to determine whether there is a difference in presentation or outcome according to the location of the intracranial tumor.

METHODS: A MEDLINE search of all English language articles pertaining to trilateral retinoblastoma published between 1977-1997 was performed. A total of 94 different cases were identified and analyzed.

RESULTS: The gender was male in 39 patients (41.5%), female in 50 patients (53.2%), and unknown in 5 patients (5.3%). Family history for retinoblastoma was positive in 44 patients (46.8%), negative in 39 patients (41.5%), and unknown in 11 patients (11.7%). The median age at the time of diagnosis of retinoblastoma was 6 months. The median time interval to the development of an intracranial tumor from the time of diagnosis of retinoblastoma was 21 months. In 78 patients (83.0%) the intracranial tumor was in the pineal region and in 16 patients (17.0%) it was in the suprasellar region. The median time interval from the time of diagnosis of retinoblastoma to the development of a pineal region tumor was 24 months whereas the median time interval for the development of a suprasellar region tumor was 1 month. At 6 months after the diagnosis of intraocular tumors, 6 of 61 children with pineal region tumors and 10 of 14 patients with suprasellar region tumors had developed intracranial disease (P = 0.005). Unilateral intraocular retinoblastoma associated with intracranial tumor was more likely to occur in patients with suprasellar region tumors than pineal region tumors (P < 0.015). The median survival after the diagnosis of an intracranial tumor was 6 months regardless of the location of the intracranial tumor. For patients who received no treatment for the intracranial tumor the median survival was 1 month whereas it was 8 months for those who received treatment. Children who were asymptomatic at the time of diagnosis of the intracranial tumor had a better overall survival than those who were symptomatic (P = 0.002).

CONCLUSIONS: The prognosis of children who develop trilateral retinoblastoma is dismal with current treatment strategies. Tumors of the suprasellar region present earlier than tumors of the pineal region after the diagnosis of intraocular tumors. Because patients who were asymptomatic at the time of diagnosis of intracranial disease had a better overall survival than those who were symptomatic, screening for intracranial tumors may be a valuable strategy in the management of patients with bilateral and/or hereditary retinoblastoma. [See editorial on pages 3-5, this issue.]