The Growth of Murine Lymphomatous Tumour-cells as Determined by Host Survival-time

Summary (1) A cell-dose-survival-time method of study has been developed for the LSA ascites lymphoma of C57Bl/Ka mice for the intraperitoneal and intravenous inoculation of tumour-cells. (2) A growth-model using survival-time as end-point has been experimentally studied. The generation time, as determined indirectly by survival-time, conforms with estimates of this parameter by direct means and suggests that murine lymphomatous tumour-cells grow exponentially during much of their growth in vivo under a given set of conditions. The mean rate of tumour-cell growth may differ according to site of growth. Death apparently occurs at a critical tumour-cell number in the range of inocula studied. (3) Methods are described for the handling of the experimental data, for the estimation of the generation time, for the threshold number of tumour-cells which, when present in the host, may result in its death. (4) Whole-body x-irradiation given after the inoculation of the tumour-cells will prolong the survival-time by predictable periods of time.