Fig. 1

Different uptake of ¹⁸F-FDG on PET according to the expression level of PD-L1 within tumor cells. a 80-years old male with poorly differentiated adenocarcinoma (p-T2bN0M0); PET showed increased accumulation of ¹⁸F-FDG (white arrow) with SUV_max of 10.2 in the primary site corresponding to CT (white arrowhead). Immunohistochamical finding of this resected primary lesion exhibited high expression of PD-L1 with more than 50%. b 63-years old male with squamous cell carcinoma (p-T1bN0M0); moderate uptake of ¹⁸F-FDG (white arrow) with SUV_max of 5.6 was observed in the primary site corresponding to CT (white arrowhead). Moderate expression of PD-L1 with 1–49% was assessed in this resected primary site by immunohistochemistry. c 68-years female with well differentiated adenocarcinoma (p-T1bN0M0); PET revealed weak accumulation of ¹⁸F-FDG (white arrow) with SUV_max of 2.4 in the primary site corresponding to CT (white arrowhead). Immunohistochamical finding of this resected primary lesion displayed no expression of PD-L1 with less than 1%