38 Adrenal Masses on Computed Tomography

CLINICAL IMAGAGINGAN ATLAS OF DIFFERENTIAL DAIGNOSIS

EISENBERG

DR. Muhammad Bin Zulfiqar PGR-FCPS III SIMS/SHL

• Fig GU 38-1 Cushing syndrome due to functioning cortical adenoma. A 4-cm mass in the left adrenal gland (arrows) is seen posterior to the tail of the pancreas and anterior to the kidney (K). The arrowhead points to the normal right adrenal gland.30

• Fig GU 38-2 Cushing syndrome due to adrenal hyperplasia. Although the adrenal glands are enlarged (arrows), their normal configuration is maintained. (K, kidneys.)30

• Fig GU 38-3 Cushing's syndrome due to adrenal hyperplasia. There is thickening of the limbs of the left adrenal gland but a normal right adrenal gland. The prominent intra-abndominal fat and hepatic steatosis are typical findings in this disease.41

• Fig GU 38-4 Aldosteronoma. There is a well-circumscribed left adrenal mass (arrow).41

• Fig GU 38-5 Adrenal carcinoma. Large soft-tissue tumor (T) invading the anteromedial aspect of the left kidney (K) and left crus of the diaphragm (arrow).42

• Fig GU 38-6 Adrenal carcinoma causing adrenogenital syndrome. Large mass in the left upper quadrant (arrows) displacing the spleen (S) anteriorly. Multiple round metastases are present in the liver.43

• Fig GU 38-7 Metastasis. Huge irregular low-attenuation mass representing an adrenal metastasis from oat cell carcinoma of the lung. The left adrenal gland (arrow) is normal.

• Fig GU 38-8 Metastases. Bilateral adrenal metastases (arrows) in a patient with colonic carcinoma. A large liver metastasis (arrowheads) is also present.30

• Fig GU 38-9 Metastasis. Typical attenuation and washout pattern of metastasis. (A) Unenhanced scan in a man with lung cancer shows an enlarged left adrenal gland (arrow) with irregular margins and attenuation of 40 HU. (B) On the dynamic enhanced phase image, there is only a minimal increase in attenuation to 53 HU. (C) On the 10-minute delayed image of the left adrenal gland (arrow), there is persistent enhancement (56 HU). The lack of significant washout is consistent with an adrenal metastasis.41

• Fig GU 38-10 Adenoma. Smooth, well-defined left adrenal mass (arrow) with typical low attenuation.41

• Fig GU 38-11 Adenoma. Typical attenuation and washout pattern of adenoma. (A) Unenhanced scan in a woman with a history of breast cancer shows a left adrenal mass (arrow) with an attenuation of 4 HU, consistent with an adenoma. (B) On the dynamic enhanced phase image, the adrenal gland (arrow) enhances vigorously to 54 HU. (C) On the 10-minute delayed image, the attenuation of the left adrenal gland (arrow) is 23 HU (lower than that of the normal right adrenal gland, kidneys, and liver). The greater than 50% washout is diagnostic of an adenoma and confirms the finding on the initial unenhanced scan.41

• Fig GU 38-12 Myelolipoma. Incidentally discovered right adrenal mass containing a small amount of fat (arrow). Note the calcification within the lesion.44

• Fig GU 38-13 Pheochromocytoma (spectrum of appearances). (A) Unenhanced scan shows a heterogeneously attenuating mass in the right adrenal gland (arrow). (B) Contrast scan shows a mass in the right adrenal gland (arrow) with peripheral enhancement and a central area of low attenuation due to necrosis. (C) Unenhanced scan shows a mass with cystic and solid components in the left adrenal gland. (D) Contrast scan shows a cystic adrenal lesion with a calcified rim (arrow).45

• Fig GU 38-14 Ectopic pheochromocytoma. (A) Soft-tissue mass (arrow) adjacent to the aorta and in front of the left renal vein. (B) Scan taken at a higher level demonstrates that both the right and the left adrenal glands are normal (arrows).46

Fig GU 38-15 Lymphoma. Bilateral adrenal masses (straight arrows). Note the destructive lymphomatous lesion involving the right rib (curved arrow).41

• Fig GU 38-16 Hemorrhage. Unenhanced scan obtained two days after motor vehicle accident shows an enlarged right adrenal mass (arrow) with an attenuation value of 53 HU. The mass was not present on CT scans acquired at admission (not shown).41

• Fig GU 38-17 Hydatid cyst. Large mass filled with daughter cysts that produce a honeycomb appearance.47

• Fig GU 38-18 Lymphangioma. Lobulated cystic mass with calcified septa.47

• Fig GU 38-19 Hemangioma. Scans (A) before and (B) after contrast injection show a well-circumscribed soft-tissue mass with punctate calcification (arrow in A) and peripheral nodular enhancement (arrow in B).47