Magnetic resonance characterization of pheochromocytomas in the abdomen and pelvis: imaging findings in 18 surgically proven cases.
OBJECTIVE
To study the magnetic resonance imaging characteristics of adrenal and extra-adrenal pheochromocytomas in the abdomen and pelvis.


METHODS
We retrospectively reviewed 18 cases of pathologically proven cases of pheochromocytomas in the abdomen and pelvis. These patients have undergone magnetic resonance imaging evaluation before surgery. The study population included 10 men and 7 women (age range, 19-68 years; mean, 38 years). A consensus review of the magnetic resonance images was performed by 2 blinded expert observers. A qualitative evaluation was completed, and the tumors were classified by anatomical location, shape, T2 signal, contrast enhancement, and signal dropout on chemical shift pulse sequences.


RESULTS
On T2-weighted images, most lesions demonstrated mild to moderate increased signal intensity (SI) (n = 12), 5 lesions demonstrated a markedly increased SI, and only 1 lesion demonstrated an isointense SI on T2-weighted images.Five lesions demonstrated marked postcontrast enhancement. Three lesions demonstrated moderate enhancement, and 5 lesions demonstrated mild postcontrast enhancement.The pattern of enhancement was variable: 4 salt and pepper, 4 homogeneous, 3 heterogeneous, and 2 target with central necrosis and hemorrhage. None of the lesions contained significant amount of intracellular lipid, as no lesions demonstrated greater than 16.5% signal dropout on out-of-phase compared with in-phase pulse sequences.
Elsayes
Khaled M
KM
Department of Radiology, University of Michigan Health System, Ann Arbor, MI 48109-0030, USA. kelsayes@med.umich.edu
Menias
Christine O
CO
Siegel
Cary L
CL
Narra
Vamsidhar R
VR
Kanaan
Yassine
Y
Hussain
Hero K
HK
D000008:Abdominal Neoplasms / Q000473:pathology*; D000328:Adult; D000368:Aged; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010386:Pelvic Neoplasms / Q000473:pathology*; D010673:Pheochromocytoma / Q000473:pathology*; D012189:Retrospective Studies; D055815:Young Adult
D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA