Imaging of Adrenal Incidentalomas with PET Using 11C-Metomidate and 18F-FDG

Journal of Nuclear Medicine

Anne Roivainen¹  Pirjo Nuutila¹  Kjell Någren¹  Anna Salonen¹  Heikki Minn¹  Johan Friberg¹  Tapio Viljanen¹  Jaakko Långsjö¹  Matti Välimäki¹  Jorma Salmi¹ 

关键词: adrenal gland;    PET;    radionuclide imaging;    metomidate;    ¹⁸F-FDG;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

Our aim was to evaluate the use of PET with 11C-metomidate and 18F-FDG for the diagnosis of adrenal incidentalomas. Methods: Twenty-one patients underwent hormonal screening before dynamic imaging of the upper abdomen with 11C-metomidate, and for 19 of these 21 patients, static 18F-FDG imaging followed. Uptake of 11C-metomidate and 18F-FDG in incidentalomas was quantified and correlated with the hormonal work-up and the mass size on CT (median, 2.5 cm; range, 2–10 cm). Results: The final diagnoses were hormonally active adenoma (n = 7), nonsecretory adenoma (n = 5), adrenocortical carcinoma (n = 1), pheochromocytoma (n = 2), benign noncortical tumor (n = 2), normal adrenal (n = 1), and malignant noncortical tumor (n = 3). Diagnosis was established at surgery (n = 9), percutaneous biopsy (n = 4), or follow-up (n = 8). The highest uptake of 11C-metomidate, expressed as standardized uptake value (SUV), was found in adrenocortical carcinoma (SUV = 28.0), followed by active adenomas (median SUV = 12.7), nonsecretory adenomas (median SUV = 12.2), and noncortical tumors (median SUV = 5.7). Patients with adenomas had significantly higher tumor–to–normal-adrenal 11C-metomidate SUV ratios than did patients with noncortical tumors. 18F-FDG detected 2 of 3 noncortical malignancies but failed to detect adrenal metastases from renal cell carcinoma. All inactive and most active adenomas were difficult to detect with 18F-FDG against background activity, whereas both pheochromocytomas and adrenocortical carcinoma showed slightly increased uptake of 18F-FDG. There was no correlation between uptake of 11C-metomidate or 18F-FDG and mass size. Conclusion: 11C-Metomidate is a promising PET tracer to identify incidentalomas of adrenocortical origin. 18F-FDG should be reserved for patients with a moderate to high likelihood of neoplastic disease.

【 授权许可】

Unknown