Values of growth fraction and cell loss factor of sixty-five tumours re-examined

It has been shown that the mathematical evaluation of data from many cell kinetic experiments, published up to 1977, was rather inaccurate. The discrepancies between published values of growth fraction (GF) and the cell loss factor phi, and the results of new calculations based on the same values of LI, Td, TC, TG1, TS and TG2, are sometimes surprising. Using a suitable approximation of ex-1, the known formulae for GF and phi are replaced by simpler ones of sufficient accuracy. This may help to avoid computational errors in future cell kinetic studies of tumours.