Endocrine Abstracts

Objectives: Surgery of pheochromocytomas (PC) still carries a high risk of hemodynamic complications during the perioperative period. We aimed to evaluate the influence of their secretory phenotype and preoperative alpha-blocker treatment on surgical outcome.

Design: A retrospective monocentric study at a tertiary medical center.

Patients: 80 consecutive patients operated for an adrenal PC between 1988 and 2018.

Results: Initial diagnosis of PC was based on typical symptoms and signs in 72% of patients, genetic testing in 16% and work-up of an adrenal incidentaloma in 12%. A genetic predisposition was however found in 34% of index cases. Most patients (78/80) were cured by surgery but a relapse of the tumor was observed in 5 cases, after a median delay of more than 10 years, and malignant behavior was observed in 7 (9%). About 92% of the patients had a secreting PC; more than 2/3 had an adrenergic phenotype and less than 1/3 a noradrenergic phenotype. Biochemically silent PCs (n=6) were asymptomatic and of smaller size, while noradrenergic tumors were the largest ones but did not significantly differ in their clinical presentation compared with adrenergic PCs. Regarding outcome, the rate of peroperative hemodynamic complications was not influenced by the secretory phenotype, but persistent hypertension after surgery, recurrence and malignant behavior were all more frequently observed in patients with a noradrenergic tumor. Preoperative alpha-blocker treatment was given for 14 days or more in 29 patients (36%) and, although being more symptomatic at diagnosis, these patients had less often hemodynamic complications (10% vs. 24% in non-treated patients, P=0.05).

Conclusions: PCs are nowadays frequently diagnosed in asymptomatic patients, although most of these tumors still exhibit a secretory phenotype, which is adrenergic in 2/3 and noradrenergic in 1/3 of cases. The occurrence of hemodynamic complications during surgery is not significantly affected by this phenotype in our study, but noradrenergic tumors show a worst post-surgical outcome, with persistent hypertension and a higher rate of recurrence or malignant behavior. Our data also provide some support in favor of a prolonged (>14 days) alpha-adrenergic blocker preoperative preparation, at least in patients with a secretory PC.