Determinants for malignancy in surgically treated adrenal lesions

It is difficult to definitively rule out or establish malignancy pre-operatively in patients with adrenal lesions referred for adrenal surgery. The aim of this study was to identify risk factors for a malignant diagnosis in patients treated with adrenalectomy.

Consecutive adrenalectomies at the Department of Surgery, Lund University Hospital between 2000 and 2009 were identified. Pre-operative clinical, radiological and biochemical data, as well as details on the operation and histology, were retrieved from patients' medical records.

There were 175 adrenal operations in 172 patients (98 female and 77 male). There were 28 malignancies. Malignant tumours were larger than in benign cases (p = 0.003), had radiological signs of malignancy more often (p = 0.001) and the patients were more likely to have a history of malignancy (p = 0.001). There were no differences regarding age, gender, body mass index or mode of detection (incidental vs. clinical) between patients with benign and malignant diagnoses. A unilateral uptake on fluorine-18 deoxyglucose positron emission tomography was more frequent in malignant cases than in benign; however, this association did not reach statistical significance.

Size of adrenal lesion, suspicious radiological findings and history of malignancy were factors associated with malignancy.