Incidence of Pineal Gland Cyst and Pineoblastoma in Children With Retinoblastoma During the Chemoreduction Era.

PURPOSE: To report on the frequency of cysts and tumors of the pineal gland in patients with retinoblastoma. DESIGN: Observational retrospective case control study. METHODS: SETTING: Institutional. STUDY POPULATION: Four hundred eight patients treated for retinoblastoma from January 2000 to January 2012 at Wills Eye Institute, Philadelphia, Pennsylvania, USA. OBSERVATION PROCEDURE: Magnetic resonance imaging (MRI) features of the pineal gland were evaluated in all patients with retinoblastoma. Characteristics of patients with pineal cysts and pineoblastoma were reviewed. MAIN OUTCOME MEASURES: Comparison of frequency of pineal gland cyst and pineoblastoma in children managed with systemic chemoreduction vs other methods. RESULTS: Of 408 patients, treatment included systemic chemoreduction in 252 (62%) and nonchemoreduction methods in 156 (38%). Overall, 34 patients (8%) manifested pineal gland cyst and 4 (1%) showed pineoblastoma. Of all 408 patients, comparison (chemoreduction vs nonchemoreduction) revealed pineal cyst (20/252 vs 14/156, P = .7) and pineoblastoma (1/252 vs 3/156, P = .1). The pineal cyst (n = 34) (mean diameter 4 mm) was asymptomatic (n = 34), followed conservatively (n = 34), and with minimal enlargement (n = 2, 9%) but without progression to pineoblastoma. The cyst was found in 22 germline and 12 nongermline patients (P = .15). Among the 4 patients with pineoblastoma, all had germline mutation and 2 had family history of retinoblastoma. Among all patients with family history of retinoblastoma (n = 45), 2 (4%) developed pineoblastoma. The pineoblastoma was asymptomatic in 2 patients and symptomatic with vomiting and headache in 2 patients. The mean interval from date of retinoblastoma detection to pineal cyst was 2 months (median 2, range 0-8 months) and to pineoblastoma was 27 months (median 28, range 7-46 months). Management included aggressive chemotherapy and radiotherapy, with 2 survivors. [ABSTRACT FROM AUTHOR]