CTLA4 and pneumonitis: Although in a large phase III trial, no benefit of blockade of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) after radiotherapy was observed in metastatic prostate cancer [33], clinical trials, such as NICOLAS (NCT02434081) and DETERRED (NCT02525757), investigating concurrent PD-(L)1-directed immunotherapy and chemoradiotherapy in patients with locally advanced lung cancer, have confirmed efficiency at modest toxicity rates, particularly with respect to pneumonitis, which is one of the most threatening complications in NSCLC patients [34–36].