Purpose: A decision tree in diagnosis of incidentally detected adrenal masses (incidentaloma) was made on the basis of these results.
Methods: The clinical usefulness of adrenal scintigraphy with 131I-adosterol and ultrasonically guided tumor biopsy was investigated in 44 patients.
Results: Adrenal scintigraphy was performed in 32 patients, of whom 21 were found to have an increased uptake in the tumor, including 19 cases of cortical adenoma and 2 of hematoma. No abnormal uptake was found in the remaining 11 patients, including 2 of cortical adenoma, 1 of adrenocortical oncocytoma and 8 of non-cortical tumors. Adrenal scintigraphy was thus thought to be useful in the differentiation of cortical tumor from non-cortical tumor, showing the sensitivity of 86%, the specificity of 80% and the diagnostic accuracy of 84%. Cytological or histological study on specimens obtained by percutaneous adrenal tumor biopsy was performed in 19 patients, of whom 18 (95%) were correctly diagnosed in terms of the malignancy of incidentaloma.
Conclusions: Taken together, the differential diagnosis and the surgical indication of adrenal incidentaloma could be made successfully based on adrenal scintigraphy and tumor biopsy.