The Chemotherapy Program of the National Cancer Institute has among its major goals the development of new antineoplastic drugs. Its research program requires that all new drugs be clinically tested against a panel of six signal tumor types: adenocarcinoma of the breast, adenocarcinoma of the colon, bronchogenic carcinoma, acute lymphatic leukemia, acute myelocytic leukemia, and non-Hodgkin's poorly differentiated lymphoma. One of the difficulties in the clinical evaluation is the testing of new drugs against the uncommon or rare tumor types, such as functioning islet cell tumors of the pancreas. The history and development of streptozotocin outlines one approach to this