APOMAB-immunoPET imaging analysis demonstrated that mice receiving a combination of chemotherapy and anti-PD-1 therapy showed significantly higher tumour uptake of 89Zr-APOMAB compared to chemotherapy alone, with highest tumour uptake observed on day 10 (33.1 ± 6.4%ID/g combination vs 23.6 ± 3.3%ID/g chemotherapy alone; p = 0.0005) (Fig. 4E). This evidence concerns the gene PDCD1 and neoplasm.