Incidence of adrenal incidentaloma on CT scan is:

Adrenal lesions discovered during imaging performed for unrelated reasons are referred to as incidentalomas. This definition excludes tumors discovered on imaging studies performed for evaluating symptoms of hormone hypersecretion or staging patients with known cancer. The incidence of these lesions identified by CT scans ranges from 0.4 to 4.4%. Ref: Schwaz's principle of surgery 9th edition, chapter 38.