Clinical variations of trilateral retinoblastoma: a report of 13 cases.

Of 440 consecutive children with retinoblastoma whom we treated between April 1972 and April 1992, 13 (3%) developed a midline intracranial neoplasm. Four of these 13 patients had bilateral familial retinoblastoma, 7 had bilateral sporadic retinoblastoma, and 1 patient had unilateral familial retinoblastoma. The twin brother of the latter patient developed pinealoblastoma without retinoblastoma. In this series, the incidence of trilateral retinoblastoma was 8% of all bilateral familial retinoblastoma and 5% of all bilateral sporadic retinoblastoma. The retinoblastoma was diagnosed at a mean age of 4.5 months and the midline intracranial tumor was diagnosed at a mean age of 23 months. The mean time interval between the diagnosis of retinoblastoma and the intracranial tumor was 22 months (range, 0 to 48 months). Seven patients (55%) were asymptomatic and their intracranial neoplasm was found on routine brain-imaging studies. The primary intracranial neoplasm had a pineal location in 10 cases and parasellar location in three cases. Despite aggressive combined treatment, 12 patients (92%) have died at a mean interval of 11 months after the diagnosis of intracranial malignancy. The mean survival of patients with midline intracranial neoplasm who were asymptomatic was significantly longer than that of symptomatic patients (P = .05).(ABSTRACT TRUNCATED AT 250 WORDS)