OBJECTIVE: This study aimed to comprehensively evaluate the performance of fluorine-18 fluorodeoxyglucose ( METHODS: Twenty-nine patients with FHRCC were prospectively enrolled from May 2020 to February 2023 for RESULTS: Primary/recurrent and metastatic lesions showed FDG avidity, without metabolic differences between them. In our analysis, SUVmax of whole body (WB-SUVmax), SUVpeak of whole body (WB-SUVpeak), MTV of whole body (WB-MTV), and TLG of whole body (WB-TLG) were associated with the expression of PD-L1. The optimal cut-off values of WB-SUVmax, WB-SUVpeak, WB-MTV, and WB-TLG for predicting positive PD-L1 expression were 9.86 (AUC 0.814), 6.92 (AUC 0.848), 19.61 cm