Familial colloid cyst of the third ventricle: case report and review of associated conditions.

The cases of a father and his son who were diagnosed with pathologically confirmed colloid cysts of the third ventricle are presented. The familial occurrence of this tumor is rare and suggests that genetic factors may play a role in its formation. Consistent with the concept that the cyst originates as a developmental abnormality, it is associated with a variety of congenital defects. The conditions that are associated with these tumors are discussed.