Familial colloid cysts: not a chance occurrence.

Area of Science:

• Neuro-oncology
• Genetics
• Neurosurgery

Background:

• Colloid cysts are rare, benign tumors of the third ventricle, with a population prevalence of approximately 1 in 5800.
• Sudden death due to obstructive hydrocephalus is a known, albeit rare, presentation of colloid cysts.
• While often considered sporadic, emerging evidence suggests a potential inherited predisposition for colloid cyst development.

Purpose of the Study:

• To investigate the frequency and significance of familial colloid cyst (FCC) occurrence.
• To compare the rate of FCCs in a patient cohort with population prevalence and literature data.
• To explore the implications of FCC identification for early diagnosis and understanding genetic factors.

Main Methods:

• A prospective registry of colloid cyst patients was maintained from 1996 to 2021.
• Retrospective collection and validation of family history data for first-degree relatives.
• Calculation of familial co-occurrence rate and comparison with literature and population-based prevalence.

Main Results:

• Thirteen cases of colloid cysts with affected first-degree relatives were identified (3.4% of the cohort).
• In the cohort, 73% were symptomatic, 46.2% underwent resection, and 7.7% experienced sudden death.
• Mother-to-child transmission was the most common pattern observed (9/13 cases).

Conclusions:

• The observed familial co-occurrence rate suggests a greater-than-chance association, supporting an inherited component.
• Systematic screening for FCCs could enable earlier detection and treatment of asymptomatic or indolent cysts.
• Identifying transmission patterns may offer insights into the molecular and genetic basis of colloid cyst formation.