PREVALENCE OF ADRENAL CARCINOMA AMONG INCIDENTALLY DISCOVERED ADRENALMASSES - A RETROSPECTIVE STUDY FROM 1989 TO 1994

Background: The incidental discovery of an adrenal mass poses the prob lem of distinguishing between the frequent benign masses and the infre quent malignant ones that require surgery. Univocal guidelines to appr oach this problem are unavailable. Objective: To perform a survey of t he clinical management of incidentally discovered adrenal masses (ie, adrenal incidentalomas). Design: A multicentric retrospective analysis of hospital medical records of adrenal incidentalomas diagnosed durin g a 5-year period; the medical records were scrutinized for demographi c data and clinical details by means of a specifically tailored questi onnaire. Setting: The major surgical and medical centers of Piedmont, a northern Italian region with approximately 4 million inhabitants. Th e recruitment pattern of these centers was unselected. Patients: The d efinition of adrenal incidentaloma was limited to patients with a phys ical examination and a clinical history unindicative of adrenal diseas e. Exclusion criteria also included hypertension of suspected endocrin e origin and a history of neoplasms known to metastasize frequently in the adrenal glands. Two hundred twenty-four medical records were coll ected, and 210 were analyzed (14 excluded a posteriori). Results: Most patients were in their 50s and 60s, and women were predominantly affe cted. The frequency of adrenocortical cancer was 13% among patients op erated on. The tumor diameter was highly correlated with the risk of c ancer; a cutoff at 5 cm had a sensitivity of 93% with a specificity of 64% in discriminating between benign and malignant cortical lesions. Conclusions:: The occurrence of adrenocortical carcinoma among adrenal incidentalomas is not rare. The evaluation of the mass size is a simp le and effective method for selecting patients at risk for cancer. The indication for surgery of masses larger than 5 cm, or of masses of an y diameter that have suspicious imaging characteristics, limits unnece ssary operations and costs.