Twelve years of experience of breast cancer at the Institut Curie: improvement of survival and value of screening mammographics

The epidemiology of breast cancer in Western countries is changing mainly because the role of mammography in the diagnosis of breast cancer is now clearly established. We report the experience of the Institut Curie to demonstrate the evolution of screening strategies and their effects upon staging at the time of diagnosis. These results are necessary to evaluate long-term follow-up as well as to evolve future trials. All patients treated for breast cancer at the Institut Curie are systematically registered. The institut Curie constitutes a reference centre in the Paris urban community with the recruitment of 1 out of 12 of all breast cancers registered in France. From 1981 to 1993, 13 248 cancers were registered. During this period the number of cancers detected as T0–T1 increased from 22.9 to 53.1%, while the number of T2 decreased from 44 to 34%, and T3 cancers from 20.5% to 7.3%. The rate of detection by screening mammography, in the absence of any organised campaign, leading to referral to the Institut Curie, rose from 4% to 34% over the same 12-year period. During the same period conservation therapy as a first treatment increased from 20 to 63% of patients. The 5-year survival, regardless of stage, rose from 77% in 1981 to 85% in 1985 P < 0.0001. We can conclude there has been an improvement in the early detection rate over the last 10 years in parallel with an improvement in survival in our Institute. This improvement is probably related to information programmes directed towards doctors and to the general public. The increasing number of small tumours and especially in situ carcinomas, demonstrated by mammographic screening justifies the development of specific therapeutic trials of these lesions. Follow-up of such trials will need to be longer than that of trials conducted in invasive tumours, and this must be taken into account in the design of these trials