Pheochromocytoma is an unusual tumor in the pediatric age group. Several aspects serve to differentiate children with pheochromocytoma from their adult counterparts. Children have fewer malignant tumors, more extraadrenal tumors, and greater bilaterality and multiplicity of tumor. Similarly, they have an increased incidence of multiple endocrine neoplasia (MEN) and familial disease. The records of 16 children (age 17 years and younger) with pheochromocytoma were evaluated. One newborn died at 36 hours of age, and a 3-year-old died four days after exploratory laparotomy. Of the 14 survivors (with an average follow-up of 8 years), three had manifestations of multiple endocrine neoplasia type 2 and two had familial pheochromocytoma only. One patient had malignant paragangliomas. Three patients had bilateral tumors; one of these had MEN. Four patients underwent operation before the use of alpha- and beta-adrenergic blockade was routine at our institution. An additional patient received blockade in preparation for the removal of the pheochromocytoma but was not prepared for preoperative angiography. Hypertensive complications were encountered in four of these five children; in one, this complication was fatal. There were no intraoperative complications in the 12 patients who had received appropriate blocking agents. Eleven of the 14 survivors are currently normotensive without the need for antihypertensive medication. Two patients have medically controlled hypertension, and one continues to have severe hypertension. An overview of this series underscores the characteristic features of pheochromocytoma in the pediatric age group. Angiography has been replaced by high-resolution computed tomography for localization.(ABSTRACT TRUNCATED AT 250 WORDS)