More recently, Quigley et al. (194) reported on preclinical PET imaging in low PD-L1-expressing MDA-MB-231 human breast carcinoma and H2009 human lung adenocarcinoma tumor xenograft murine models using WL-12 conjugated to another chelator – TRAP – and radiolabeled with gallium-68. This evidence concerns the gene CD274 and lung adenocarcinoma.