In 1987, an editorial in the Journal that accompanied a report of high-dose interleukin-2 (IL-2) therapy for cancer (1, 2) asked whether the field of immunotherapy was at “the beginning of the end” or “at the end of the beginning”. In retrospect, it was at the “beginning of the beginning”. Have we made progress since then? Finn, in her review of tumor immunology in this issue, answers emphatically in the affirmative, and the report by Hunder et al, also in this issue,(xxx) underscores the remarkable potential of the immune system to eradicate cancer, even when the disease is widespread.

It has long been known that graft-versus-tumor effects underlie the success of allogeneic bone marrow transplantation for hematological neoplasms and the efficacy of donor lymphocyte infusions in chronic myelogenous leukemia (3). These results show that the immune system can eradicate a cancer, just as it can reject an allogeneic organ unless the recipient receives potent immunosuppressive agents. However, since the immune system perceives most cancers as “self”, the allograft rejection mechanism is not often operative in cancer patients.