[A case of pheochromocytoma associated with neurofibromatosis type 1].

Pheochromocytoma occurs in 0.1 to 5.7% of patients with type 1 neurofibromatosis (NF1). Radiological findings of pheochromocytoma are often similar to those of neurofibroma; therefore, any pheochromocytoma should be excised in hypertensive patients with NF1. A 60-year-old male patient with NF1 was referred to this hospital for an incidentally discovered right adrenal mass, 7 x 6 mm in diameter. The patient had multiple benign tumors and suffered from hypertension for 4 years. Laboratory findings showed increased serum and urine catecholamine levels. Magnetic resonance imaging (MRI) revealed a high signal intensity on T2-weighted images, which was enhanced by gadolinium contrast. The mass was positive for 131 I-metaiodobenzylguanidine (MIBG) scintigraphy. A laparoscopic adrenalectomy was performed. A histopathological diagnosis of pheochromocytoma was made. The patient's post-operative course was uneventful, and blood pressure was normalized. Screening of the adrenal tumor is strongly recommended for NF1 patients with hypertension, since any unfavorable events due to catecholamine such as cardiomyopathy and fatal arrhythmia can be avoided by adequate surgical intervention.