Characteristic species dependent growth patterns of mammalian neoplasms

Evidence is presented, arising from an analysis of published data on tumour growth in three species of laboratory animals and in human multiple myeloma supporting a species specific relation between two supposedly independent parameters in the Gompertz equations frequently used to quantify tumour growth curves. This evidence supports the conjecture of Norton et al. (1976), based on their observations of the growth kinetics of a murine melanoma and a rat mammary carcinoma, that such a relation may be a general feature of tumour growth. Published data on the growth of xenografts of human colorectal tumours in immune-deprived mice suggests that the observed growth relation reflects the ability of a particular species to support a tumour of a certain maximum size. The existence of this relation greatly simplifies the task of predicting complete patterns of undisturbed neoplastic growth in these species.