Niemeijer et al. [91] published a study using radiolabeled anti-PD-1 monoclonal antibody 89Zr-nivolumab in patients with advanced NSCLC and showed a significant 89Zr-nivolumab tumour uptake, that was higher in patients with immunohistochemically proven PD-1 positive tumour-infiltrating immune cells as compared with PD-1 negative tumours. Here, PDCD1 is linked to neoplasm.