Introduction A few adrenal masses may elude characterization on cross-sectional imaging and remain indeterminate. These include lipid-poor adenomas, adrenal metastases and carcinomas and phaeochromocytomas. It is important to distinguish between them, as phaeochromocytomas can be fatal if operated without preoperative blockade. Their clinical spectrum varies, from dramatic symptoms and signs including paroxysmal headache, flushing, diaphoresis, hypertension, tachycardia, to minimal or no symptoms whatsoever. Clinically and biochemically silent phaeochromocytoma is a rare entity.
Case port: We present here a 63 years old woman referred to our department with an incidentaloma of the right adrenal gland on an abdominal computed tomography scan performed because of chronic back and right subchondral pain. She reported mild, non paroxysmic hypertension well controlled with a combined angiotensin II receptor blocker/thiazide diuretic. She had a cholocystectomy and bilateral hip arthroplasty 5 and 2 years ago. Her physical examination was unremarkable.
The lesion was 4×4.6 cm in size with regular contour, an unenhanced CT attenuation score of 23 HU and delayed contrast medium washout. 1 mg overnight dexamethasone suppression test excluded autonomous cortisol secretion. Aldosterone/renin ratio was normal. Urinary fractioned metanephrines and normetanephrines were in the reference range.
Because of the indeterminate nature of the adrenal mass, she was referred for open adrenalectomy which finally was performed laparoscopically. Intraoperatively the patient developed acute hypertensive crisis successfully controlled with nitroprusside. Pathologic examination of the adrenal mass revealed a pheochromocytoma scored 6 according to the PASS scoring system.
Conclusion We present the case of a clinically and biochemically silent phaeochromocytoma which provoked an adrenergic spell during surgery. Malignant lesions and phaeochromocytomas may share common characteristics as intense enhancement and slower contrast washout. Suspicious radiologic findings should increase the medical alertness for the possibility of a catecholamine-secreting tumor. Minimal handling of the tumor and perioperative vigilance to combat potential hypertensive crisis are the cornerstones in managing such cases.