Bilateral adrenocortical adenomas causing Cushing's syndrome. Report of two cases with enzyme histochemical and ultrastructural studies and a review of the literature.

Patient 1 (a 50-year-old woman) with bilateral adrenocortical adenomas causing Cushing's syndrome underwent right-sided adrenalectomy. After an interval of 4 years 5 months, she underwent left-sided tumorectomy. Patient 2 (a 46-year-old woman) underwent bilateral tumorectomy after a frozen-section diagnosis. Each adrenal contained a single macronodule that consisted of compact cells, clear cells, and oxyphilic cells, which had characteristic enzyme histochemical and ultrastructural features. In addition, the adrenals had a so-called pigmented nodule and extracapsular small focus of compact and clear cell proliferation in case 2. The nonnodular part of the cortex was atrophic in both cases. Fourteen patients (mean +/- SD age, 42.5 +/- 5.55 years) with bilateral adrenocortical adenomas associated with Cushing's syndrome have been described in the literature. Thirteen (93%) of the patients were female. Three patients had unilateral or bilateral multiple adenomas. While the earlier described patients underwent bilateral total adrenalectomy, those in recent reports had part of the adrenal resected unilaterally or bilaterally (ie, tumorectomy). The above features are useful in differentiating bilateral adrenocortical adenoma from other types of bilateral adrenocortical lesions.