[Residual tumor mass and other kinetic parameters of clinical relevance in cancer of the breast].

Based on data about illness-free survival obtained studying a group of 192 patients affected by breast cancer, we have made some calculations about tumoral growth kinetics, using the theoretical presumptions of the exponential model. Tumoral recurrence in the different stages (S-I = 35%, S-II = 38%, S-III = 53% y S-IV = 72%) were valued. Also the theoretical mean time of tumoral relapse was determined for each clinical stage of the illness (S-I = 4.6 years, S-II = 2.6 years, S-III = 1.9 years and S-IV = 1.2 years). Knowledge of these relapse time values makes it finally possible to value the residual tumoral mass after treating the primary in each clinical stage under study (S-I = 1.2 X 10(6) cells, S-II = 8.1 X 10(7) cells, S-III = 3.6 X 10(8) cells and E-IV = 1.6 X 10(9) cells). Comparison of the theoretical data obtained with the corresponding clinical data (real appearance time of relapses, percentage of patients of each Stage that have metastasis, etc.) shows that the formulations and theoretical concepts used, describe, with a certain degree of preciseness, the ordinary clinical observations phenomena that characterize the evolutive course of the breast carcinoma.