(European Society for Medical Oncology) Immunotherapy has been a major breakthrough in oncology — but little is known about its safety for HIV-positive cancer patients. A study to be presented at the ESMO 2018 Congress in Munich has now provided data to suggest that treatment with PD-1/PD-L-1 immune checkpoint inhibitors, which target the very system affected by the HIV virus, is feasible in this patient population for whom cancer is currently one of the principal cause of mortality.