Congenital brain tumors have been reported infrequently and their management remains ill defined. An 11-year review (1977-1987) of all children with brain tumors with the onset of symptoms before 1 year of age was completed. Twenty-two children with the following histological diagnoses were treated: astrocytoma (7 patients), primitive neuroectodermal tumor (6 patients), papilloma or carcinoma of the choroid plexus (3 patients), malignant teratoma (2 patients), dermoid tumor (2 patients), embryonal rhabdomyosarcoma (1 patient), and chloroma (1 patient). Fifteen tumors were supratentorial in location, and 7 were infratentorial. Initial symptoms were hydrocephalus (32%), focal neurological deficit (23%), asymptomatic increase in head circumference (18%), failure to thrive (14%), and seizures (4.5%). The goal of treatment was a radical excision when possible, with primary chemotherapy in the last 6 years of the review period. Radiation therapy was the adjunct to surgery in the initial 5-year period. All patients with papillomas of the choroid plexus and dermoid lesions underwent a total resection with no recurrence. All 7 astrocytomas were supratentorial, with 6 occurring in the diencephalon. Five of the seven patients with astrocytomas survived more than 5 years. The 6 primitive neuroectodermal tumors were located equally between the supra- and infratentorial spaces. Four of the 6 infants with these tumors received chemotherapy (2 received chemotherapy alone; 2 received chemotherapy and radiation therapy) and are tumor free 2 to 9 years later. A fifth child received radiation therapy alone early in the series and survived only 4 months. The family of the other child refused adjunctive treatment.(ABSTRACT TRUNCATED AT 250 WORDS)