Cancer and human immunodeficiency virus (HIV) are both scary things to have in your body, but a new treatment is successfully using the latter against the former. Recent news reports, among others in the New York Times, talked about this new cure for leukemia by using HIV. This mini-review puts this news in perspective and provides a broader view as there appear to be several areas where clinical research on HIV and leukemia seem to connect. The topics covered range from antiviral gene therapy approaches using HIV-based lentiviral vectors to the risk of leukemia induction by these integrating vectors, and from an anti-leukemia transplantation strategy that turned out to provide a functional cure for HIV, to novel vaccination approaches.