Surgical Treatment of Malignant Pheochromocytoma and Paraganglioma: Retrospective Case Series.

INTRODUCTION: Pheochromocytoma and paraganglioma (PPGL) are rare neoplasms; about 10% are malignant. Literature regarding possible benefit from resection is extremely limited.

METHODS: A 20 year review of all patients undergoing surgery for malignant PPGL at the Mayo Clinic Rochester Campus between 1994 and June 2014 was performed.

RESULTS: We identified 34 patients undergoing surgery for malignant PPGL. Median follow up was 6 and 5 years survival was 90% (median 11 years). Complete resection (R0) was achieved in 14 patients (41%). Median disease-free survival was 4.6 years for patients with R0 resection (up to 12 years). Only eight patients (23%) were disease-free on last follow up. Elevated preoperative fractionated metanephrines or catecholamines were documented in 23 patients (68%); these normalized in 13 of 23 patients (56%) postoperatively-with symptom relief in 15 of 18 preoperatively symptomatic patients (79%). Among 23 patients with hormone-producing tumors, significant reduction in number of antihypertensive medications was also noted postoperatively; 11 patients have remained off all antihypertensives, 6 required 1 medication, 1 required 2, while 5 required full blockade with phenoxybenzamine and a beta-adrenergic blocker.

CONCLUSION: Surgery plays a significant role in the management of selected malignant PPGL. Resection can be effective in normalizing or significantly reducing levels of catecholamines and metanephrines, and can improve hormone-related symptoms and hypertension. Surgical resection, either complete or incomplete, is associated with durable survival despite a high rate of tumor recurrence.