[Chronology of breast cancer using Gompertz' growth model].

The chronology of carcinoma of the breast based upon the size of the primary tumour and of its metastatic nodes in a simple exponential growth model leads to anomalies. The Gompertz model may be substituted for it in order to date the primary tumour and its metastases at the price of a hypothesis: the asymptotic size of the carcinoma. Its value has little influence on the initial doubling times chosen as a new time unit. 337 radical mastectomy specimens out of 500 examined fulfilled the necessary conditions for a precise quantitative study. If the age of the lesion expressed by taking the initial doubling time as a time unit is called K, the mean age of the primary carcinoma at the time of the first metastasis (FM) is K = 35. Its size is 15 mm3 and its diameter 3 mm. 90% of lymph node metastases occurred at K = 43 (size of primary carcinoma 125 mm3; diameter 6 mm). These results are in agreement with others obtained on theoretical or experimental bases. They tend to show that the earliest diagnosis, taking technical possibilities into account, cannot be early enough to precede lymphatic spread.