Preoperative 18F‐FDG Uptake is Strongly Correlated with Malignancy, Weiss Score, and Molecular Markers of Aggressiveness in Adrenal Cortical Tumors

BACKGROUND: Adrenal incidentaloma are frequent in the general population. It can be difficult to diagnose adrenocortical carcinomas among them, even with the progress of imaging techniques. We studied the results of PET-FDG in the diagnosis of such tumours. METHODS: We studied patients referred to the Department of Endocrine Surgery at La Timone Hospital, Marseilles, France, between June 2006 and October 2010 for adrenal tumours. All patients underwent a complete work-up (biological tests and imagery), completed with PET-FDG. We compared the results of PET-FDG and molecular analysis with Weiss score and clinical follow-up. We calculated correlations with the Pearson test. RESULTS: A total of 51 patients were studied. We found that PET-FDG had a sensitivity of 95% and specificity of 97% for the diagnosis of adrenocortical carcinoma. The correlation between PET-FDG and Weiss score was 77% (P ≤ 0.0001). Molecular analyses were correlated as well with Weiss score and malignancy (P < 0.05). CONCLUSIONS: The nature of atypical adrenal masses can be difficult to define during preoperative investigations. For undetermined tumours smaller than 6 cm, characterization with PET-FDG can be one more diagnostic argument pointing to malignancy. It could potentially change the therapeutic strategy and surgical management. In our experience, molecular analyses are available after surgery and have less impact on the therapeutic strategy than PET-FDG. Preoperative PET-FDG can be an asset in the management of adrenal incidentaloma and adrenocortical carcinoma.