CTLA4 and head and neck squamous cell carcinoma: Importantly, as with EBRT, here we observe that this effect of TRT is correlated with increased response to immune checkpoint blockade resulting in improved survival with the combination of 90Y-NM600 and dual anti-CTLA-4 and anti-PD-L1 in the immunologically cold MOC2 syngeneic murine model of head and neck squamous cell carcinoma 32, 33.