Evaluation of the Multiplication Rate of Human Cancer through the Study of Growth Diagrams

Abstract

The determination of growth rates in human tumors is studied through growth diagrams obtained with radiographic or direct measurement (made several times) from the diameters of round neoplastic nodes. The mathematic development of two different growth models, one, more common, based on the dimensional increase of tumor dependent from the dual fission of all the neoplastic cells, the second based on the intervention of biological factors, which reduce, variously at different times, the quota of the cellular population active for reproduction, showed different «periods of reproduction». A third system to ascertain the « period of reproduction » of a neoplastic cells population, is based on the study of the diagrams concerned with the variation in time of the growth rate ∊: owing to the rhythm of the waves it is probable that these are dependent from the predominant phase of the cellular cycle at the time the cellular population is examined. It is suggested that it would be more realistic and closed to the biological reality to obtain the value on the « periods of reproduction » through the last two systems, the mathematic and graphic analyses of which are presented. These studies may give the basic biometrical values necessary for the planning of fractionation of irradiation therapy according to the neoplastic cellular cycle.