An Unusual Cause of Adrenal Mass in Neurofibromatosis Type 1: Malignant Peripheral Nerve Sheath Tumor

A malignant peripheral nerve sheath tumor (MPNST) is an aggressive tumor that can arise from the malignant transformation of benign neurofibromas in patients with neurofibromatosis type 1 (NF1). MPNST occurs in 2% of patients with NF1, contributing to significant mortality in these patients. Here, we report the case of a 67-year-old female with a known history of neurofibromatosis type 1 who was referred to general surgery after the discovery of a large left-sided adrenal mass on CT imaging five months earlier. Lab workup revealed elevated urine catecholamines, concerning pheochromocytoma. As pheochromocytoma is also common in those with NF-1, appropriate medical management followed by surgical resection was performed. The final pathology report revealed an MPNST.