Pediatric colloid cysts: a multinational, multicenter study. An IFNE-ISPN-ESPN collaboration
Authors: Roth Jonathan , Perekopaiko Yurii , Kozyrev Danil A. , Constantini Shlomi , _ _ , _ _ , Myers Hannah E. , Chern Benjamin L. , Reisner Andrew , Mena-Bernal Jose Hinojosa , Bartoli Andrea , Paun Luca , Bakhshi Saqib Kamran , Shamim M Shahzad , Talamonti Giuseppe , Scott R. Michael , Shimony Nir , Damaty Ahmed El , Mierez Rodrigo , Silva José , Sánchez Gustavo , Rita Andrea Di , Genitori Lorenzo , Spacca Barbara , Felissi Yacine , Morsli Abdelhalim , Cardozo-Faust Giselle , Shukla Dhaval , Srinivas Dwarakanath , Sudevan Kevin Jude , Amarouche Meriem , Grotenhuis J. André , Boogaarts Hieronymus D. , Márquez-Rivas Javier , Rivero-Garvia Mónica , Vloo Philippe De , Van Calenbergh Frank , Schroeder Henry W. S. , Marx Sascha , Refaee Ehab El , Ozgural Onur , Bayatli Eyüp , Kahiloğulları Gökmen , Jayamohan Jayaratnam , Mangano Francesco T. , Skoch Jesse M. , Vadivelu Sudhakar , Stevenson Charles B. , Fonseca Ricardo Brandao , Faquini Igor , Alsuwaihel Mosaab , McNeely P. Daniel , Giannetti Alexandre Varella , Lorincz Katalin , Schuhmann Martin , de-Ribaupierre Sandrine , Gump William C. , Giordano Flavio , Jallo George I. , Goodden John , Sataite Ieva , Catapano Domenico , Thomale Ulrich-W. , Schulz Matthias , Massimi Luca , Tamburrini Gianpiero , Cinalli Giuseppe , Spennato Pietro , Jecko Vincent 
Published: February 2022

OBJECTIVE
Colloid cysts (CCs) are rare at all ages, and particularly among children. The current literature on pediatric CC is limited, and often included in mixed adult/pediatric series. The goal of this multinational, multicenter study was to combine forces among centers and investigate the clinical course of pediatric CCs.

METHODS
A multinational, multicenter retrospective study was performed to attain a large sample size, focusing on CC diagnosis in patients younger than 18 years of age. Collected data included clinical presentation, radiological characteristics, treatment, and outcome.

RESULTS
One hundred thirty-four children with CCs were included. Patient age at diagnosis ranged from 2.4 to 18 years (mean 12.8 ± 3.4 years, median 13.2 years, interquartile range 10.3–15.4 years; 22% were < 10 years of age). Twenty-two cases (16%) were diagnosed incidentally, including 48% of those younger than 10 years of age. Most of the other patients had symptoms related to increased intracranial pressure and hydrocephalus. The average follow-up duration for the entire group was 49.5 ± 45.8 months. Fifty-nine patients were initially followed, of whom 28 were eventually operated on at a mean of 19 ± 32 months later due to cyst growth, increasing hydrocephalus, and/or new symptoms. There was a clear correlation between larger cysts and symptomatology, acuteness of symptoms, hydrocephalus, and need for surgery. Older age was also associated with the need for surgery. One hundred three children (77%) underwent cyst resection, 60% using a purely endoscopic approach. There was 1 death related to acute hydrocephalus at presentation. Ten percent of operated patients had some form of complication, and 7.7% of operated cases required a shunt at some point during follow-up. Functional outcome was good; however, the need for immediate surgery was associated with educational limitations. Twenty operated cases (20%) experienced a recurrence of their CC at a mean of 38 ± 46 months after the primary surgery. The CC recurrence rate was 24% following endoscopic resection and 15% following open resections (p = 0.28).

CONCLUSIONS
CCs may present in all pediatric age groups, although most that are symptomatic present after the age of 10 years. Incidentally discovered cysts should be closely followed, as many may grow, leading to hydrocephalus and other new symptoms. Presentation of CC may be acute and may cause life-threatening conditions related to hydrocephalus, necessitating urgent treatment. The outcome of treated children with CCs is favorable.