Massive Pheochromocytomatosis Treated With Cytoreductive Surgery

A 35-year-old woman presented in 2022 to the Carling Adrenal Center with recurrent palpitations, anxiety, and diaphoresis, 9 years after right laparoscopic adrenalectomy at a local hospital for pheochromocytoma, diagnosed during pregnancy with placental abruption. Biochemical evaluation revealed markedly elevated 24-hour urinary and plasma fractionated metanephrines. Imaging identified extensive intra-abdominal tumor implants and a solitary liver lesion, raising suspicion for pheochromocytomatosis vs metastatic disease. Genetic testing was negative for major known pathogenic variants. Cytoreductive surgery successfully resected more than 200 tumor deposits, including a 15.5 cm omental mass, without complications. Pathology confirmed pheochromocytomatosis, with the liver lesion identified as focal nodular hyperplasia. Postoperatively, symptoms resolved, biochemical markers significantly improved but remain at ∼2.5- to 3.8 times above normal range, indicating residual microscopic disease (40 months follow-up). This case highlights the feasibility of cytoreductive surgery for extensive pheochromocytomatosis and the challenging distinction between tumor seeding and metastatic pheochromocytoma, emphasizing the need for lifelong biochemical surveillance.