The good, the bad, and the ugly: uncommon CT appearancesof pheochromocytoma
Renu Berry· Kiran Busireddy · Linda C. Chu · Pamela T. Johnson · Elliot K. Fishman
Abdominal Radiology (2022) 47:1406–1413

90% are sporadic and 10% are part of syndromes

• von Hippel-Lindau syndrome (10-26%)
• MEN Type II (50%)
• Neurofibromatosis Type 1 (1%)
• Pheochromocytoma-Paraganglioma Syndromes Associated with SDHB and SDHD Mutation

“In a 7-year period at a single institution, 40 patients, 70% of new cases of surgically proven pheochromocytoma, were initially detected by serendipity.”
Serendipity in the diagnosis of pheochromocytoma.
Oshmyansky AR et al
J Comput Assist Tomogr. 2013 Sep-Oct;37(5):820-3

“ Pheochromocytomas are often considered the great mimicker of other adrenal tumors. Because of their varied clinical, imaging, and pathologic appearances, accurate diagnosis can be challenging.”
Pheochromocytoma: The Range of Appearances on Ultrasound, CT, MRI, and Functional Imaging
Leung K et al.
AJR 2013; 200:370-378

“Pheochromocytoma is a rare neuroendocrine tumor arising in the adrenal medulla, which accounts for elevated blood pressure in a small minority of adults with hypertension and is benign in 90% of cases. Nonetheless, identification is important because uncontrolled catecholamine secretion increases the risk of serious cardiovascular complications. Approximately 11–21% of patients are asymptomatic, while others may present with symptoms mistaken for underlying cardiovascular conditions (e.g., palpitations) .” 
The good, the bad, and the ugly: uncommon CT appearances of pheochromocytoma 
Renu Berry · Kiran Busireddy · Linda C. Chu · Pamela T. Johnson· Elliot K. Fishman
Abdom Radiol (NY). 2022 Apr;47(4):1406-1413.

”The classic pheochromocytoma is a round or oval, hypervascular, heterogeneously enhancing mass. The early intense enhancement is reportedly due to its capillary-rich framework. Vascular pheochromocytomas can exceed washout thresholds on adrenal protocol CT and be mistaken for a lipid-poor adenoma. Accordingly, adrenal protocol CT washout is not reliable for distinguishing these two pathologies. If the venous enhancement level exceeds 130 HU, the lesion is more likely a pheochromocytoma. If the adrenal mass is detected incidentally on arterial phase CT, arterial phase attenuation of 110 HU or higher is not typical of adenoma but is characteristic of pheochromocytoma. Arterial phase enhancement of > 110 HU was 58% sensitive and 100% specific for pheochromocytomas in one study.”
The good, the bad, and the ugly: uncommon CT appearances of pheochromocytoma 
Renu Berry · Kiran Busireddy · Linda C. Chu · Pamela T. Johnson· Elliot K. Fishman
Abdom Radiol (NY). 2022 Apr;47(4):1406-1413.

”Pheochromocytomas have the highest heritability among all endocrine tumors, with nearly 35–40% being hereditary in origin. The occurrence of bilateral pheochromocytomas is 10% in sporadic cases, 50–80% in multiple endocrine neoplasia type II (MEN2), and 40–80% in Von Hippel–Lindau (VHL). In patients with bilateral pheochromocytoma, a syndromic cause should be considered, most common being MEN2A or MEN2B, neurofibromatosis type 1 (NF-1), and hereditary pheochromocytoma paraganglioma (HPP) syndrome.”
The good, the bad, and the ugly: uncommon CT appearances of pheochromocytoma
Renu Berry · Kiran Busireddy · Linda C. Chu · Pamela T. Johnson· Elliot K. Fishman
Abdom Radiol (NY). 2022 Apr;47(4):1406-1413.