Endocrine Abstracts

Background: The clinical diagnosis of pheochromocytoma requires improved clinical reasoning due to the scarcity of symptoms and complementary tests that are not always confirmatory.

Clinical case: A 58-year-old female patient sought an endocrinology service at the University Hospital for investigation of Adrenal tumor on the right, measuring 3.8×4.5×3.8 cm, discovered during routine ultrasound. He reported vague symptoms of abdominal discomfort and had been using irregular metropolol for more than ten years, due to mild hypertension and rare palpitations. Serial laboratory studies were carried out for Adrenal Incidentaloma which showed a only slight increase in Urinary Normetanephrines (1.2 ULN). No other evidence of hormonal excess was detected. During the entire clinical investigation, with suspension of antihypertensive medication for hormonal evaluation, the patient remained asymptomatic. Clinically, there was no evidence of pheochromocytoma. He was followed up on an outpatient basis for two years with urine metanephrine levels and image monitoring. The case was discussed in a clinical session with a radiology service and the characteristics suggested as the most likely hypothesis Adrenal Hemangioma, the tumor was lobulated, defined limits, hypodense and with peripheral calcifications, with heterogeneous contrast enhancement initiated in the arterial phase, and with a tendency to homogenization in the portal and late phases. Absolute wash out 37 and relative wash out 33. After two years of follow-up, she presented paroxysmal atrial fibrillation, and amiodarone was started. Service without availability of plasma metanephrines. PET-CT-FDG was performed detecting an Adrenal nodular lesion on the right, measuring 4×3.9 cm, indicating neuroendocrine tumor and whole body scintigraphy with MIBG-SPECT CT with nodular uptake in the right adrenal. The patient underwent a right adrenalectomy after preparation with alpha adrenergic block. She underwent major bleeding in the liver bed and hypovolemic shock. After surgery, the patient remained hemodynamically stable. Immunohistochemistry study confirmed the diagnosis of pheochromocytoma.

Conclusion: The diagnosis of pheochromocytoma requires clinical skill and the use of several diagnostic resources that, combined, help to clarify the clinical situation.

Reference

Williat J, Chong S Ruma JA, Int J Endocrinol. 2015, Pheochromocytoma and Paraganglioma: An Endocrine Society Guideline, June, 2014.