Non-invasive evaluation of the incidentally detected indeterminate adrenal mass.
ABSTRACT Clinically silent adrenal masses are discovered incidentally during diagnostic testing or treatment for clinical conditions that are not related to suspicion of adrenal disease; thus, they are commonly referred to as 'incidentalomas'. The widespread use of high-resolution anatomic imaging techniques such as computed tomography (CT) and magnetic resonance (MR) imaging has led to the increased detection of these masses. In many patients without a known extra-adrenal primary malignancy--and even in patients with a primary neoplasm--most adrenal masses ultimately prove to be benign. However, it remains important that these adrenal masses are accurately characterized to exclude the treatable causes of adrenal disease, and also to accurately stage the oncology patient. The purpose of this chapter is to describe the findings and recent advances in non-invasive imaging methods that are now available for the accurate characterization of incidentally detected adrenal masses (i.e. the differentiation of benign from malignant masses). The imaging techniques and the algorithms that are used in our institution for the evaluation of incidentally detected adrenal mass will be described.
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ABSTRACT: To determine the efficacy of various magnetic resonance (MR) imaging sequences for the differentiation of adrenal masses. Fifty-three adrenal masses in 46 patients (adenomas, metastases, myelolipomas, hemorrhages, and pheochromocytomas) were evaluated by means of T1-, T2-, and T2*-weighted sequences, calculated T2 values, chemical shift imaging techniques, and dynamic contrast material-enhanced imaging. The Student t test and receiver operating characteristic analysis were used to evaluate the differences in the groups of masses. Analysis of the chemical shift-induced signal intensity of the adrenal masses and the T2*-weighted sequence enabled differentiation of adenomas, metastases, and pheochromocytomas. Adenomas and pheochromocytomas were also differentiated by means of a heavily T2-weighted sequence. Signal intensity values for all masses overlapped. Although a chemical shift imaging technique and a T2*-weighted sequence helped correctly differentiate among the groups of adrenal masses, the degree of overlap suggests that it is still difficult to evaluate disease in individual patients.Radiology 08/1994; 192(1):41-6. · 6.34 Impact Factor
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ABSTRACT: Our aim was to evaluate adrenal adenomas in patients who underwent both unenhanced CT and chemical shift MRI to determine if adenomas can be characterized with MRI when the findings of CT are indeterminate. Between January 1999 and June 2003, 40 patients (42 adrenal masses) underwent unenhanced CT and chemical shift MRI and were retrospectively analyzed. Hounsfield units, adrenal-to-spleen chemical shift ratio, and signal-intensity index were obtained for each adrenal mass. Qualitative analysis for loss of signal in each adrenal mass on the opposed-phase images was also performed by two reviewers and compared with the quantitative analyses. A lipid-rich adenoma was diagnosed if the mass measured equal to or less than 10 H, had an adrenal-to-spleen chemical shift ratio of less than 0.71, and had a signal-intensity index of greater than 16.5% or if the mass fulfilled two of the preceding criteria and had follow-up imaging without change. The sensitivities and specificities for diagnosing a lipid-rich adenoma using the qualitative, adrenal-to-spleen chemical shift ratio, signal-intensity index, and unenhanced CT attenuation analyses were 92% (33/36) and 17% (1/6), 100% (36/36) and 100% (6/6), 100% (36/36) and 67% (4/6), and 78% (28/36) and 83% (5/6), respectively. Twenty-eight (67%) lipid-rich adenomas measured equal to or less than 10 H, had an adrenal-to-spleen chemical shift ratio of less than 0.71, and had a signal-intensity index of greater than 16.5%. Eight masses (19%) measured greater than 10 H but had an adrenal-to-spleen chemical shift ratio of less than 0.71 and a signal-intensity index greater than 16.5% and were unchanged at follow-up. Eight (62%) of 13 adrenal adenomas measuring greater than 10 H on unenhanced CT were definitively characterized with chemical shift MRI.American Journal of Roentgenology 08/2004; 183(1):215-9. · 2.90 Impact Factor
Article: Adrenocortical cytopathology.[show abstract] [hide abstract]
ABSTRACT: Cytopathologic smears and/or imprints of human adrenal cortex (9 cases) and its disorders were examined, including adrenocortical nodule (3 cases), adrenocortical adenoma (23 cases), carcinoma (8 cases), and renal cell carcinoma (6 cases). Immunocytochemistry directed against 3 beta-hydroxysteroid dehydrogenase and adrenal-4-binding protein (Ad4BP), a transcription factor in steroidogenesis, was also performed. There were no cytologic differences between normal adrenal and adrenocortical nodules. Large nuclei with prominent nucleoli were observed predominantly in adrenocortical neoplasms. Cellular atypia or pleomorphism and the degree of cohesiveness were unreliable criteria in differentiating between adrenocortical adenoma and carcinoma. Mitosis and necrotic materials were observed only in adrenocortical carcinoma. These cytologic findings were considered contributory, but not diagnostic when evaluating adrenocortical disorders because of marked intra-tumoral heterogeneity. There were no reliable cytologic criteria in differentiating adrenocortical and renal cell carcinoma. Immunocytochemistry of 3 beta-hydroxysteroid dehydrogenase and especially Ad4BP was demonstrated to aid greatly in the differential diagnosis between these carcinomas by identifying adrenocortical parenchymal cells.American Journal of Clinical Pathology 09/1995; 104(2):161-6. · 2.88 Impact Factor