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Radiology > GENITOURINARY
Adrenal Carcinoma
Article Last Updated: Mar 1, 2005
AUTHOR AND EDITOR INFORMATION
Section 1 of 12  
Author: Robert L Cirillo Jr, MD, MBA, Assistant Professor of Radiology, Florida State University College of Medicine; Medical Interventional Radiologist, Director/CEO, South Georgia Vascular Institute and South Georgia Laser Vein Center
Robert L Cirillo, Jr, is a member of the following medical societies: American College of Physician Executives, Cardiovascular and Interventional Radiological Society of Europe, Society for Vascular Technology, and Society of Interventional Radiology
Editors: Glenn Krinsky, MD, Chief of Abdominal Imaging Section, Associate Professor, Department of Radiology, New York University School of Medicine; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Arnold C Friedman, MD, FACR, Associate Chairman, Department of Radiology, University of Florida Health Science Center; Chief, Department of Radiology, Shands-Jacksonville Hospital; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center
Author and Editor Disclosure
Synonyms and related keywords:
adrenal cancer, adrenal gland carcinoma, adrenal gland cancer, cancer of the adrenal gland, carcinoma of the adrenal gland
Background
Adrenocortical carcinoma is a rare malignancy with a poor prognosis. The reported incidence of adrenal carcinoma is 2 cases per million persons. When identified, tumors frequently are large, measuring 4-10 cm in cross-sectional diameter. Adrenal carcinomas arise from the adrenal cortex and are bilateral in up to 10% of patients. Approximately 50-80% are functional tumors, with most causing Cushing syndrome.
Pathophysiology
The adrenal glands reside within the Gerota fascia. The cortex and medulla comprise the 2 functional components of the adrenal gland; anatomically, the gland is composed of a body and lateral and medial limbs.
Frequency
United States
Adrenal carcinoma has an incidence of 1 case in 1,700,000 adults. Adrenal carcinoma accounts for 0.002% of childhood malignancies.
Mortality/Morbidity
Adrenal carcinoma accounts for 0.02% of malignant tumors and 0.2% of cancer deaths.
Race
Adrenocortical carcinoma has no racial predilection.
Sex
Male-to-female ratio is approximately 1:1; however, functional tumors are slightly more common in women, while nonfunctional tumors are slightly more common in men. Male patients with adrenocortical carcinoma often tend to be older than female patients and often have a worse prognosis.
Age
Adrenocortical carcinoma has a bimodal occurrence, with the first peak in the first decade of life and the second peak in the fourth to fifth decades of life.
Although adrenocortical carcinoma is rare in adults, it is even more uncommon in children, comprising only 0.002% of childhood malignancies. In children, adrenal carcinoma is rare and is responsible for only 6% of adrenal tumors, although it is the most common adrenal cortical cancer. In children, 90% of adrenal masses are neuroblastomas (adrenal medulla). Adrenal carcinomas in children are associated with hemihypertrophy and Beckwith-Wiedemann syndrome.
Anatomy
The adrenal gland is composed of the main body, a lateral limb, and a medial limb and often has a characteristic inverted Y, V, or T shape. On CT, the limbs should demonstrate a thickness no greater than that of the adjacent diaphragmatic crus. The right adrenal gland lies anteromedial to the superior pole of the right kidney in a space bordered by the inferior vena cava, liver, and right crus of the diaphragm. The left adrenal gland lies more caudal than the right adrenal gland. It is located anteromedial to the superior pole of the left kidney in a space bordered by the left crus of the diaphragm and splenic vein and is posterior to the pancreas. The adrenal gland is made up of the cortex and the medulla, which are derived from the mesoderm and the neural crest, respectively. The adrenal cortex secrets cortisol, aldosterone, and androgens, while the adrenal medulla secretes epinephrine and norepinephrine.
Arterial supply of the adrenal gland arises from 3 main vessels. The superior adrenal artery originates in the inferior phrenic artery, the middle adrenal artery branches directly off the aorta, and the inferior adrenal artery is a branch of the renal artery.
Venous drainage is simpler, with the adrenal vein entering directly into the vena cava on the right. On the left, the adrenal vein enters into the inferior phrenic vein before exiting into the left renal vein.
Clinical Details
Patients usually present with a large palpable mass, abdominal pain, or Cushing syndrome. Primary adrenocortical carcinomas are large tumors usually measuring more than 5 cm at presentation. Because they are large, the organ of origin often is difficult to determine (Image 1). Cushing syndrome is the most common clinical presentation in adults with adrenal cortical carcinoma, although Cushing syndrome results from adrenal carcinoma in only 5-10% of patients. Conversely, Cushing syndrome in childhood usually is caused by adrenocortical carcinoma. Clinical presentation depends on whether the tumor is functional. In addition to Cushing syndrome, patients can present with virilization, feminization, precocious puberty, or Conn syndrome, although these manifestations are rare. In children, the most common clinical presentation is virilization, followed by Cushing syndrome. Functional tumors more often are detected in female patients than in male patients. They often are detected earlier than nonfunctional tumors because of the secretion of hormones. The following endocrine syndromes are associated with adrenocortical carcinoma:
- Cushing syndrome
- Virilization and precocious puberty
- Feminization
- Primary hyperaldosteronism
Preferred Examination
CT is the study of choice in the evaluation of an abdominal mass or, more precisely, to differentiate a benign adrenal mass from a malignant lesion.
Limitations of Techniques
Although CT is used most widely for evaluating abdominal masses, the origin of the mass often is difficult to discern. In addition, the presence or absence of invasion of adjacent structures is difficult to determine in some patients.
Pheochromocytoma
Other Problems to be Considered
Metastatic disease
Findings
Because adrenal carcinomas are often large at presentation, radiographs of the abdomen may demonstrate mass effect from the tumor. The calcifications observed in more than 30% of patients are often more difficult to detect with abdominal radiographs than with on CT scanning.
On excretory urography, adrenal carcinoma often causes mass effect on the ipsilateral superior pole of the kidney, usually displacing the upper pole of the kidney laterally and, when large enough, inferiorly.
With the advent of cross-sectional imaging, the evaluation, staging, and treatment of adrenocortical carcinoma has vastly improved. CT should be the first imaging of choice to define an adrenal mass such as adrenocortical carcinoma.
Findings
On CT, adrenocortical carcinoma appears as a large mass, often with central necrosis. Calcification is observed in as many as 30% of patients.
On unenhanced images, heterogeneity is often found with larger masses. On enhanced images, the tumor enhances heterogeneously, with the greatest enhancement often at the periphery and often irregular.
CT findings that increase the index of suspicion for adrenocortical carcinoma include the following:
- Large mass (>4 cm)
- Central necrosis or hemorrhage
- Heterogeneous enhancement
- Invasion into adjacent structures
- Venous extension into the renal vein or inferior vena cava
Degree of Confidence
Occasionally, differentiating an adrenal carcinoma from other pathology in the upper abdomen may be difficult because the mass is large and the fat planes are indistinct. In these patients, multiplanar MRI is the better imaging test. In particular, the imaging findings of large pheochromocytomas and metastasis may be identical. Therefore, it may be prudent to obtain spot vanillylmandelic acid (VMA) or metanephrines prior to resection to prevent a hyperintensive crisis as not all pheochromocytomas are clinically overt.
False Positives/Negatives
False-positive lesions could include exophytic renal masses and exophytic pancreatic tail masses.
Findings
MRI often demonstrates a large mass with lower signal intensity than the liver on T1-weighted images and higher signal intensity than the liver on T2-weighted images. Often, the tumor demonstrates heterogeneously hyperintensity on T1- and T2-weighted images, due to the central necrosis and hemorrhage. Because the mass usually does not contain any significant intracellular lipid, it will not lose signal on out-of-phase imaging.
Coronal and sagittal images may be helpful in determining adrenal origin of the mass, thus differentiating it from renal cell carcinoma or hepatocellular carcinoma, especially if CT is equivocal.
Degree of Confidence
MRI is advantageous for evaluating tumors, since its depiction of vascular invasion and extension into surrounding structures often is superior to that of CT. Additionally, the most cephalad extension of the tumor must be evaluated so that the surgeon can obtain vascular control of the tumor. This can be achieved with CT but often is easier with MRI.
False Positives/Negatives
Larger adrenal adenomas are radiologically similar to adrenal cortical carcinomas. The pathologic distinction between adrenal adenoma and adrenal carcinoma is largely based on size, with the cutoff in the range of 4-5 cm.
Findings
Adrenocortical carcinoma demonstrates a homogeneous echo texture when small, but the echo pattern becomes heterogeneous with cystic areas when the tumor grows as a result of hemorrhage and necrosis.
Degree of Confidence
Because different planes are obtainable on ultrasonography, it is helpful in some patients to determine the organ of origin of the mass.
Findings
Nuclear scintigraphy does not play much of a role in the evaluation of adrenal carcinoma, except to exclude other lesions such as pheochromocytomas or aldosteronomas. Iodine I 121 metaiodobenzylguanidine (MIBG) and indium In 111 octreotide can be used to visualize pheochromocytomas, while iodine I 131 6-beta-iodomethyl-19-norcholesterol (NP-59) can be used to detect aldosteronomas or other hyperfunctioning cortical tumors. Positron emission tomography imaging performed with fluorine-18 fluorodeoxyglucose (FDG) has shown some promise in differentiating benign adrenal lesions from malignant lesions.
Findings
Prior to cross-sectional imaging, arteriography was the preferred modality for evaluating abdominal masses. On angiograms, adrenal carcinomas are usually hypovascular masses, which helps distinguish them from hypernephromas. Little vascular shunting, puddling, or venous laking is found with adrenal carcinoma compared to renal cell carcinoma. Usually, faint tumor vascularity is seen on abdominal aortograms, and it is not until selective adrenal arteriography is performed that tumor vessels are identified. The predominant arterial supply to the adrenal gland and to adrenal carcinoma is the superior adrenal artery off the inferior phrenic artery.
Arterial embolization can be performed in adrenal carcinoma, usually as a presurgical procedure to decrease the vascularity or size of the tumor. Embolization can be performed with coils or Gelfoam. Sclerosing the feeding vessels with absolute alcohol is another option. Treatment of all 3 vessels (superior, middle, and inferior adrenal arteries) is necessary.
| Media file 1:
A 68-year-old woman with a large right upper quadrant primary adrenocortical carcinoma with curvilinear calcification. Low-attenuation regions anteriorly are consistent with necrosis. |
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Media type: CT
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| Media file 2:
A 67-year-old man with a heterogeneous mass superior to the right kidney |
 | View Full Size Image | |
Media type: CT
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| Media file 3:
CT demonstrates a large heterogeneous mass, with flocculent calcifications and central necrosis (same patient as Picture 2). |
 | View Full Size Image | |
Media type: CT
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| Media file 4:
T2-weighted MRI demonstrates a large right adrenocortical carcinoma with high signal intensity involving the right lateral aspect. |
 | View Full Size Image | |
Media type: MRI
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- Agrons GA, Lonergan GJ, Dickey GE, Perez-Monte JE. Adrenocortical neoplasms in children: radiologic-pathologic correlation. Radiographics. Jul-Aug 1999;19(4):989-1008. [Medline].
- Allolio B, Hahner S, Weismann D, Fassnacht M. Management of adrenocortical carcinoma. Clin Endocrinol (Oxf). Mar 2004;60(3):273-87. [Medline].
- Boushey RP, Dackiw AP. Adrenal cortical carcinoma. Curr Treat Options Oncol. Aug 2001;2(4):355-64. [Medline].
- Cirillo RL Jr, Bennett WF, Vitellas KM, et al. Pathology of the adrenal gland: imaging features. AJR Am J Roentgenol. Feb 1998;170(2):429-35. [Medline].
- Dackiw AP, Lee JE, Gagel RF, Evans DB. Adrenal cortical carcinoma. World J Surg. Jul 2001;25(7):914-26. [Medline].
- Dunnick NR. Adrenal carcinoma. Radiol Clin North Am. Jan 1994;32(1):99-108. [Medline].
- Dunnick NR. Hanson lecture. Adrenal imaging: current status. AJR Am J Roentgenol. May 1990;154(5):927-36. [Medline].
- Fishman EK, Deutch BM, Hartman DS, et al. Primary adrenocortical carcinoma: CT evaluation with clinical correlation. AJR Am J Roentgenol. Mar 1987;148(3):531-5. [Medline].
- Hutter AM Jr, Kayhoe DE. Adrenal cortical carcinoma. Clinical features of 138 patients. Am J Med. Oct 1966;41(4):572-80. [Medline].
- Kay R, Schumacher OP, Tank ES. Adrenocortical carcinoma in children. J Urol. Dec 1983;130(6):1130-2. [Medline].
- Lockhart ME, Smith JK, Kenney PJ. Imaging of adrenal masses. Eur J Radiol. Feb 2002;41(2):95-112. [Medline].
- Maurea S, Mainolfi C, Bazzicalupo L, et al. Imaging of adrenal tumors using FDG PET: comparison of benign and malignant lesions. AJR Am J Roentgenol. Jul 1999;173(1):25-9. [Medline].
- Mayo-Smith WW, Boland GW, Noto RB, Lee MJ. State-of-the-art adrenal imaging. Radiographics. Jul-Aug 2001;21(4):995-1012. [Medline].
- Ng L, Libertino JM. Adrenocortical carcinoma: diagnosis, evaluation and treatment. J Urol. Jan 2003;169(1):5-11. [Medline].
- Vierhapper H. Adrenocortical tumors: clinical symptoms and biochemical diagnosis. Eur J Radiol. Feb 2002;41(2):88-94. [Medline].
Adrenal Carcinoma excerpt Article Last Updated: Mar 1, 2005
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