Endocrine Abstracts

Objective: To assess clinical features, diagnosis, treatment and outcome in patients with pheochromocytoma surgically treated in the past 3 decades in two tertiary referral hospitals.

Methods: A retrospective study on clinical and pathological characteristics, treatment, and outcome in patients with pheochromocytoma followed up in specialized neuroendocrinology units who underwent surgery in the period 1981–2016 was performed.

Results: 81 patients (45 women (56%); age 51±15 year (range, 13–76)) were studied. The tumor was sporadic in 68 patients (84%) and familial in 13 patients, more frequently in the context of a MEN type 2 (n=6).10% of the pheochromocytoma were bilateral. Most of the patients (66%) were symptomatic. The main complains were the classic triad (27%), and hypertensive crisis (27%). 40% of the pheochromocytoma were incidentally discovered on imaging investigations. 47% of patients were hypertense at diagnosis. 24-h urinary catecholamines excretion was determined in 80% of patients, being elevated in 75% of cases. Fractionated urinary metanephrines were only determined in 23% of patients, and were elevated in 84%. Abdominal CT was the most used imaging technique (87%, n=68), followed by ¹²³I-MIBG scintigraphy (54%, n=42) which detected 88% of those tumors (n=37). MRI was performed in 50% of the patients, 87% of those tumors were hyperintense in T2. 89% (n=65) patients had a preoperative alpha-adrenergic blockage. 17 patients (22%) had a complication during surgery, being hypertensive crisis the most common complication (12.5%, n=10). Median tumor diameter was 5.9±2.8 cm (range, 1.5–13). 15% of pheochromocytomas had vascular invasion, 15% had capsular invasion and 23% presented necrosis. Only 6% presented ganglionar or distant metastasis. 68 patients were followed in our two centers, 55 patients (81%) were cured, 4 of them (6%) had persistent disease and 9 (13%) had recurrence after surgery.

Conclusion: Pheochromocytoma in our series is generally a large, symptomatic and sporadic tumor. Incidentally discovered pheochromocytoma is common. Abdominal CT is the preferred imaging technique for localization. Surgical complications are common. Despite the high rate of vascular invasion in the histopathological study, ganglionar and distant metastasis are rare. The presence of cases with persistent and recurrent disease after surgery requires a long term follow-up. these tumors.