The DOM project for the early detection of breast cancer, Utrecht, The Netherlands

Abstract

This report describes the short-term results of a population-based screening programme--the DOM project--during the years 1975-1980. Screening was offered to all women in the city of Utrecht (The Netherlands) and 11 neighbouring areas who were born between 1911 and 1925. Further evaluation will be reported in future publications. The programme was organised by the Department of Epidemiology, Institute of Social Medicine (now renamed The Institute of Public Health and Epidemiology), University of Utrecht, which established a screening centre--The Preventicon--in a new commercial and shopping centre with good public transport facilities. The study population was between 50 and 65 years old at intake, a decision based on results obtained in the H.I.P. study in New York. Women resident in the city of Utrecht (n = 14,697 at intake) were screened four times, with intervals of 12, 18 and 24 months respectively between the first and fourth examinations. Women resident in the other areas (n = 8814) were screened twice with an interval of 18 months. Screening consisted of a clinical examination (inspection, palpation) and xero-mammography. An important role was played by paramedical personnel, who performed the examination and had a degree of responsibility in reading the mammograms. Initially the radiation dose per breast was about 1 rad, but from 1977 onwards this was reduced to 0.4 rad per exposure; for women living in Utrecht (4 screenings) the total dose was less than 5 rad over the 5-year period. Referral policy was based on a set of three types of "signal" to general practitioners (who coordinated specialist services): 1. Recommendation for biopsy; 2. Suggested repeat examination after 6 months; 3. Brief note on palpable abnormalities, considered likely to be benign. In Section II the response of the invited population is analysed. The response rate for the first screening was 72% in the city of Utrecht and 68% in the other areas. Variation in response rates can only be explained to a minor degree by measured demographic and sociological variables, age being the most important determinant. Women were asked to contribute D.fl. 12.50 (approx. US $5) per screening cycle to meet part of the expenses, the rest being paid by public health research funds. A total number of 61,649 examinations was performed in 23,511 women. In Section III the immediate results of screening are presented. An analysis is made of the cancer yield of the 3 signals mentioned above.(ABSTRACT TRUNCATED AT 400 WORDS)