CTLA4 and hepatitis A virus infection: In this regard, as mentioned above, it is also important to highlight differences between immunotherapy as monotherapy (nivolumab) or in combination (ipilimumab plus nivolumab); increased hepatic toxicity has been described with this combination and possibly with anti-CTLA-4 antibodies, compared to anti-PD-1/PD-L1 antibodies.[15] In our cases, unexpected toxicities appeared after the combination treatment, while the hepatitis after nivolumab seems to be similar to the standard TKI hepatitis (Fig. 3; Table 1).