[Cancer of the breast at the time of diagnosis. A national CANAM study: analysis of 3007 cases].

: Between April 1988 and February 1990, 3,007 cases of female breast cancer were recorded among people insured by CANAM*; 118 cancers were bilateral from the start and 2,889 were unilateral. At the time of diagnosis the patients' age ranged from 24 to 101 years (median: 60 years), and 35.6 percent of the tumours were virtually subclinical. Lymph node involvement was clinically absent in 75 percent of the cases and histologically absent in 57 percent. In women under 50 the proportion of small TO-T1 tumours was greater than 40 percent, which pleaded for detection before the age of 50 years. Conversely, in economically weak populations and in women who were followed up for cancerous disease, breast cancer was diagnosed at a later stage. In older (retired) women (median age: 74), who accounted for 44 percent of the whole population, the proportion of advanced tumours was practically doubled (T4: 11 percent versus 6 percent), and the probability of metastases at the time of diagnosis had risen from 4.2 to 6.1 percent. In these patients, clinical examination once a year should contribute to an earlier diagnosis.