In our study group, nonfunctioning adenomas were the most frequent cause of AI (42%), followed by cortisol-secreting adenomas (15%), metastatic disease (10%), pheochromocytomas (8%), myelolipomas (6%), cysts (6%), carcinomas (4%), lymphomas (4%), tuberculosis (4%), and aldosteronoma (2%). Only 13 lesions (25%)
were functioning (8 cortisol-secreting adenomas, 4 pheochromocytomas, and 1 aldosteronoma). Carcinomas were the largest adrenal masses (mean diameter, 11.7
± 1.3 cm). With the exception of 1 pheochromocytoma, 1 cyst, and 1 myelolipoma, all AI larger than 6 cm were carcinomas. During follow-up of 21 patients with nonsurgically treated AI for 6 to 36 months (mean, 24.8 ± 8.9), no patient had tumor reduction or disappearance. After 12 months of follow-up, however, a 45-year-old woman had adrenal mass enlargement from 3.2 cm to 4.4 cm; the excised lesion proved to be an adenoma. Moreover, evidence of cortisol hypersecretion developed after 24 months of follow-up in a 30-year-old man with a 3.5-cm adenoma in the left adrenal gland.
Why is this important to hospitalists? Because hospitalized patients have a large number of CT scans for other reasons. Due to the severity and complexity of illness in hospitalized patients these incidentalomas may be more likely to be ignored than in the ambulatory setting. Those that are acknowledged may not be communicated to the PCP.