Prevalence of adrenal incidentaloma in a contemporary computerized tomography series

Abstract

Adrenal incidentalomas, defined as masses discovered incidentally during imaging investigation of non-adrenal disorders, have become a rather common finding in clinical practice. The prevalence is not well characterized and varies among studies. The aim of the present study was to perform a prospective evaluation of the prevalence of adrenal incidentalomas among subjects undergoing computerized tomography (CT) scan of the chest in a screening program of lung cancer (Tic TAC study) in Piedmont, a region of Northwestern Italy. This evaluation included 520 subjects (382 males and 138 females, aged between 55-82 yr), referred to our hospital from April to December 2001. Twenty-three patients with adrenal masses were identified: 21 adrenal adenomas, 1 myelolipoma, and 1 metastasis of lung cancer. Therefore, the overall prevalence of adrenal lesions was 4.4%, and that of benign adrenal masses was 4.2%. This prevalence is higher than those found in previous CT scan series reported in the literature, probably because of the use of high-resolution CT scanning technology. Another factor that influenced our results is that subject age is skewed towards the decades characterized by a greater occurrence of adrenal masses. The outcome of this study confirms that we are presently able to identify incidentally discovered adrenal masses more often than in early years and that the prevalence of adrenal incidentalomas on CT images is approaching that of autopsy series. The present study provides a reliable estimate of the prevalence of adrenal incidentaloma with currently used CT scanners. Notwithstanding that our subjects were at increased risk of lung cancer, the rate of adrenal metastases was low. We think that the present results can be generalized even if we may disclose the lack of histological diagnosis.

Pros and cons of dexamethasone suppression test for screening of subclinical Cushing’s syndrome in patients with adrenal incidentalomas

“…It is, therefore, hardly surprising that the criteria for qualifying subclinical Cushing's syndrome remain controversial (4,9,20). Various diagnostic algorithms (biochemical testing procedures) have been used (1-4, 9, 10, 19, 20, 21) but they are often too complex and expensive to be applied for the endocrine work up of frequent tumours like adrenal adenomas, which may be detected serendipitously in about 4% of the patients undergoing abdominal CT (8). The overnight DST is convenient and appropriate for screening but it is still debated which cut-points and dexamethasone doses are more sound (21).…”

“…This issue has relevant implications because clinically inapparent adrenal adenomas are increasingly recognized in the course of workup or treatment of conditions that are not related to adrenal diseases (4,8). The optimal diagnostic approach to a patient who has an adrenal adenoma of incidental discovery has not been established; however, screening for subclinical Cushing's syndrome is reasonable particularly if the patient is young and has diseases potentially associated with cortisol excess.…”

cAMP signaling in cortisol-producing adrenal adenoma

“…Therefore, in the last years, subclinical hypercortisolism has been used for patients who do not fulfill the criteria either for Cushing's syndrome or for non-secreting tumors. In the last decades, the study of subclinical hypercortisolism has gained more interest because of the increasing number of cases reported in a relevant fraction of patients with adrenal incidentalomas (up to 30%) (22), which are discovered in a relatively large number of subjects (up to 4% in radiological series) (23).…”

Surgical approach in adrenal incidentalomas: Report of thirteen cases and review of the literature

“…Although when evaluated retrospectively it has been determined that these patients had complaints due to the adrenal mass or hormonal activity, they were included in the incidentaloma group for being identified coincidentally (1,2). Most incidentaloma lesions are benign and do not require treatment (3).…”