[Which adrenal incidentalomas are to be operated?]

The goal of this retrospective study was to recognize the incidence of adrenal tumors called incidentalomas, that are in fact symptomatic or hormone secreting tumors, to assess if the diagnostic criteria proposed in the literature are reliable for adrenal tumors found incidentally.

The records concerned 147 patients operated between April 1981 and December 2000 for an adrenal mass measuring 3 cm in diameter and larger on CT scan. Clinical and laboratory findings as well as hormone levels and imaging examinations (CT Scan, IRM, scintigraphy) were correlated with operative findings and results of histologic examinations. One hundred and three patients were operated by a traditional approach and forty four by videoendoscopic techniques.

In 41 patients (28%), the tumors had to be classified as false incidentalomas (group 1) postoperatively. In 106 patients (72%), the nature of tumor was non definite. In this group 2, there were ten malignant tumors, two pheochromocytomas and 94 benign lesions. Age of patient, size of tumor, increase in size over time and radiological appearance represent criteria that are not reliable to separate malignant from benign tumors.

Tumors of indeterminated and non specific nature only should be classified as incidentalomas. Imaging techniques as well as other criteria of malignancy cannot be relied upon to separate benign from malignant tumors. The risk even small of cancer or pheochromocytoma leads us to recommend excision of tumors > or = 3 cm in radiological diameter. The videoendoscopic approach is a good alternative to open operation in centers with this special expertise.