The role of 18F-FDG PET/CT in adrenocortical carcinoma: a systematic review

Adrenocortical carcinoma (ACC) is a rare and highly aggressive carcinoma with a poor prognosis. The aim of our study is to summarize existing evidence on the potential usefulness of fluorine-18-fluorodeoxyglucose positron/computed tomography (18F-FDG PET/CT) in the management of patients affected with ACC. The current systematic review was registered to the PROSPERO registry (ID1103377). A comprehensive search of the PubMed/MEDLINE, Embase, and Cochrane Library databases was conducted until July 2025. A total of 19 studies that evaluated the role of 18F-FDG PET/CT in ACC were included. One of the fields investigated was the ability of PET/CT to discriminate between adrenal masses, particularly in the differential diagnosis between benign and malignant lesions. 18F-FDG PET/CT demonstrated good sensitivity and specificity but was affected by different cutoff values of SUV and SUV ratio applied. In addition, in the staging/restaging, despite heterogeneity of data, diagnostic performances were good and higher than conventional imaging tools. Moreover, PET/CT modified patient management in 9-21% of cases. The prognostic role of 18F-FDG PET/CT remains controversial, with seven studies reporting heterogeneous findings and different endpoints investigated, primarily OS and PFS. Semiquantitative parameters such as SUVmax and SUV ratio were analyzed, but their prognostic impact was inconsistent. Despite several limitations affecting this analysis, especially related to the heterogeneity of the studies included, 18F-FDG PET/CT seems to be a useful tool for the evaluation of ACC, especially in the differential diagnosis of adrenal masses and in the staging/restaging. Instead, the prognostic impact of PET/CT and its features remains inconclusive.