Paraganglioma and Pheochromocytoma are catecholamine-producing tumors (predominantly norepinephrine, epinephrine, and dopamine alone or in combination) that can lead to life-threatening complications including myocardial infarction, heart failure, stroke, and death. Pheochromocytomas are tumors of the adrenal medulla, while paragangliomas originate from the chromaffin tissue in the extra-adrenal autonomic ganglia . The tumor is usually unilateral, and in some cases is associated to syndromes such as multiple-endocrine neoplasia II, neurofibromatosis, and Von Hippel-Lindau disease . Germline mutations of susceptibility genes associated with this disease have been recently discovered, particularly in the genes responsible for the succinate dehydrogenase complex, SDHB, SDHC, SDHD, SDHA and SDHAF2, as well as mutations in TMEM127, MAX, KIF1Bβ, EGLN1/PHD2, and HIF2A [1,2]. Less than 5% are malignant tumors, and surgical removal often offers a definite cure.
The perioperative morbidity and mortality of pheochromocytoma surgery has decreased dramatically to a rate of about 1% or less since 1960. Many factors including improvements in surgery, diagnostics, and the development of new anaesthetic techniques and perioperative monitoring capabilities have contributed to this positive development. Often this improvement has been attributed to the adoption of perioperative blockade of alpha-adrenergic receptors with long acting agents such as phenoxybenzamine. Scientific proof of this concept is not available.
For the past 20 years, the surgical approach chosen for adrenalectomy has been minimally invasive rather than open procedures. Surgical manipulations of the tumor can lead to an uncontrolled release of catecholamines with subsequent multi-system complications intraoperatively, especially cardiovascular. Hypertensive episodes, which can occur during surgery despite alpha-receptor blockade, are treated with short and fast acting agents such as sodium nitroprusside, clevidipine, nicardipine and esmolol to name a few. These agents may also be employed perioperatively as needed.
Because approximately 25-30% of these tumors are inherited, genetic testing and a follow-up for recurrent tumors as well as family screening are advisable. To avoid a bilateral adrenalectomy in case of bilateral disease or a recurrence on the contralateral side, partial resections of the adrenal gland are increasingly common when feasible.