EXPERIMENTAL TUMOR SYSTEMS - STANDARDIZATION OF ENDPOINTS

The experimental tumors that are available to research workers and the assay techniques used in measuring their response to therapy, are reviewed. The criteria necessary for choosing an appropriate model are discussed in terms of tumor origin, its transplantation history, the presence or absence of artefactual immunity and the site chosen for transplantation. It is recommended that more attention should be paid to the choice of a tumor before any series of experiments is begun. Many suitable rodent tumors are now available. The advantages and disadvantages of human tumors grown as xenografts are discussed. The techniques for measuring tumor response are divided into 2 groups: in situ assays which can also be applied to human tumors in the clinic, and clonogenic assays which involve tests of reproductive capacity of cells removed from the treated hosts. The merits of survival time, regrowth delay, local control and loss of an incorporated label are compared and contrasted with those of cell survival assays. © 1979.