FDG-PET in adrenocortical carcinoma

Adrenal cortical carcinoma (ACC) is a rare malignant neoplasm with a poor p rognosis. Radical surgery of the primary tumor and of local as well as of d istant recurrence is the only effective treatment, and requires accurate an d early localization of recurrent tumors. In this regard, we prospectively scanned 10 patients with ACC, 8 during follow-up and 2 at primary work-up. In all patients PET scans from the fleck to the upper thighs were obtained 45 minutes after injection of 370 MBq [F-18]FDG. Reading was done visually, with the investigator blinded to the results of other diagnostic Modalitie s. All known sites of ACC lesions showed markedly increased FDG uptake. In 3 patients, previously unknown lesions were identified by PET in the lung ( One lesion), the abdomen (3 lesions), and the skeleton (multiple), respecti vely. One false positive liver focus was shown by PET aside from the true p ositive lung metastases in the same patient. The sensitivity/specificity of PET based oil different organs Was 100/97%, that based on the number of PE T-detected lesions (N = 23) was 100/95%. PET altered or influenced the tumo r stage in 3/10 patients, modifying the subsequent therapeutic management i n 2/10 patients. We conclude that FDG-PET is highly useful in ACC and shoul d be included in the work-up for initial staging as well as for follow-up.