Purpose: In a retrospective study the diagnostic accuracy of computed tomography for the differentiation of benign from malignant adrenal masses in patients with extra-adrenal malignancies was evaluated. For this differentiation a new score system was tested.
Patients and methods: Size, density, structure, and borders of adrenal masses in 60 patients with extra-adrenal tumours were analysed and scored. The single criteria and the total score values were correlated with the final diagnosis achieved either by histology or by follow-up CT examinations.
Results: Score values above 4 indicated always metastases and score values below 2 were benign lesions. An overlap occurred at score values between 2 and 3 resulting in an overall accuracy of 83.3%.
Conclusion: Single CT criteria are not reliable enough to differentiate benign from malignant adrenal lesions: better results are achieved by using our scoring system.