Prevalence of adrenal incidentaloma at computed tomography (chest and abdominal) in a general hospital in Brazil

Abstract

OBJECTIVE: To prospectively determine the prevalence of incidental adrenal lesions at computed tomography (CT) at an University Hospital in Brazil. PATIENTS AND METHOD: A cross-sectional prospective study was performed to evaluate 3,382 consecutive patients with no known adrenal disease or malignancies who underwent chest and abdominal CT scans over a ten-month period. The cases of adrenal incidentaloma were defined by the presence of any change in gland contour, size or density. Kappa values were calculated, evaluating the intra and inter-observer agreement. RESULTS: One hundred and one incidental adrenal masses were identified, corresponding to 83 cases and a prevalence of 2.5% (CI 95%: 1.0%-3.2%). Male patients presented a higher prevalence of incidentaloma than female (3.3% vs. 1.5%; p= 0.01). There was a significant association between older age and higher frequency of incidentaloma. Kappa of 0.76 and 0.83 (good and excellent agreement, respectively), were obtained in evaluating the intra and inter-observer agreements. CONCLUSIONS: The prevalence of adrenal incidentaloma detected by CT was similar to that of various published retrospective clinical series. The two factors that independently influenced the distribution of incidentalomas were older age and being male.