CTLA4 and cancer: The data indicate that investigations of anti–programmed death 1 (PD1) plus anti–cytotoxic T-lymphocyte–associated protein 4 (CTLA-4) therapies in any nonmelanoma advanced cancer should be conducted along with anti-PD1 monotherapy to ensure that the net effect of the addition of anti-CTLA-4 to anti-PD1 can be clearly established for that cancer and setting and that unnecessary CTLA-4 inhibition with related toxic effects (both clinical and financial) can be avoided.