The blocking experiments demonstrated that this tracer specifically targeted in NSG/293 T/hPD-1 (the tumour uptake of blocking group vs. non-blocking group: 5.5 ± 0.1%ID/g vs. 14.8 ± 1.2%ID/g (p = 0.005) at 48 h. The gene discussed is PDCD1; the disease is neoplasm.