[Etiologies of 1 173 hospitalized cases with adrenal incidentaloma].

Objective: To summarize the characteristics of etiological distribution of adrenal incidentaloma during the past 20 years.
Methods: All the relevant data of adrenal incidentaloma patients admitted into Chinese PLA General Hospital between January 1993 and January 2013 were collected. Their gender ratio, visiting ages and final diagnoses were retrospectively analyzed.
Results: There were 1 173 patients were collected, of which, 629 (53.62%) males and 544 (46.38%) females with a mean age of (50.84 ± 12.13) years. There were 669 (57.03%) hypertensive cases and 622 cases undergone adrenalectomy. Routine medical checkup and abdominal discomfort led to the discovery of adrenal incidentalomas. As to the etiologies, there were non-functional tumors (n = 809, 68.97%), pheochromocytoma (n = 137, 11.68%), primary aldosteronism (n = 84, 7.16%) and adrenal Cushing syndrome (n = 65, 5.54%). The proportions of adrenal cortical carcinomas and metastases were 1.70% (n = 20) and 1.36% (n = 16) respectively. Compared with normotension group, the proportion of non-functional lesions in hypertension group was significant lower (73.81% vs 65.32%, P < 0.05) while the proportions of primary aldosteronism and adrenal Cushing syndrome were higher (11.96% vs 0.79%, 5.83% vs 5.18%, both P < 0.05).
Conclusion: Adrenal incidentaloma patients with concurrent hypertension is quite common. In respect of etiologies, non-functional tumor is the most common and followed by pheochromocytoma and primary aldosteronism Cushing syndrome.