the POMP regimen — and induced long-term remissions in children with acute lymphoblastic leukaemia (ALL). With incremental refinements of original regimens, using randomized clinical studies by St. Jude Children's Research Hospital, the Medical Research Council in the UK (UKALL protocols) and German Berlin-Frankfurt-Münster clinical trials group (ALL-BFM protocols), ALL in children has become a largely curable disease. This approach was extended to the lymphomas in 1963 by Vincent T. DeVita and George Canellos at the NCI, who ultimately proved in the late 1960s that nitrogen mustard, vincristine, procarbazine and prednisone — known as the MOPP regimen — could cure patients with Hodgkin's and non-Hodgkin's lymphoma. Currently, nearly all successful cancer chemotherapy regimens use this paradigm of multiple drugs given simultaneously, called combination chemotherapy or polychemotherapy. Adjuvant therapy As predicted by studies in animal models, drugs were most effective when used in patients with tumours of smaller volume. Another important strategy developed from this — if the tumour burden could be reduced first by surgery, then chemotherapy may be able to clear away any remaining malignant cells, even if it would not have been potent enough to destroy the tumor in its entirety. This approach was termed "adjuvant therapy". Emil Frei first demonstrated this effect — high doses of methotrexate prevented recurrence of osteosarcoma following surgical removal of the primary tumour. 5-fluorouracil, which inhibits thymidylate synthase, was later shown to improve survival when used as an adjuvant to surgery in treating patients with colon cancer. Similarly, the landmark trials of Bernard Fisher, chair of the National Surgical Adjuvant Breast and Bowel Project, and of Gianni Bonadonna, working in the Istituto Nazionale Tumori di Milano, Italy, proved that adjuvant chemotherapy after complete surgical resection of breast tumours significantly extended survival — particularly in more advanced cancer. Drug discovery at the NCI and elsewhere Zubrod's initiatives In 1956, C. Gordon Zubrod, who had formerly led the development of antimalarial agents for the United States Army, took over the Division of Cancer Treatment of the NCI and guided development of new drugs. In the two decades that followed the establishment of the NCCSC, a large network of cooperative clinical trial groups evolved under the auspices of the NCI to test anticancer agents. Zubrod had a particular interest in natural products, and established a broad programme for collecting and testing plant and marine sources, a controversial programme that led to the discovery of taxanes (in