A meta-analysis by Wang et al. [44] showed an overall incidence of all-grade colitis of 13.6% in patients treated with a combination therapy of ipilimumab/nivolumab, of 9.1% in patients receiving ipilimumab and of 1.3% with anti-PD-1/PD-L1 monotherapy. The gene discussed is PDCD1; the disease is colitis.