CTLA4 and lung cancer: Induction with radiation was done using a hypo-fractionated radiation regimen (a total dose of 24 Gy delivered by 8 Gy fractions) that was shown to induce systemic anti-tumor responses when combined with concomitant administration of anti-CTLA-4 or anti-PD-1 in pre-clinical models, and anti-CTLA-4 in lung cancer patients [6, 7].