OPTIMIZATION OF MAMMOGRAPHIC BREAST-CANCER SCREENING USING A COMPUTER-SIMULATION MODEL

To optimise breast cancer screening protocols, risk (induction of fata l tumors) versus benefit (reduction in the number of fatal tumors) ana lyses are performed for a simulated stable Swedish female population, using the Model for evaluation of Breast cancer Screening (MBS). The p resent study comprises, the influences of various screening parameters , i.e. ages at which screening is started and stopped, interval period between successive sessions, tumor detection limits for screening and average glandular dose per screening session. When the results of the present study are expressed in terms of numbers of fatal breast tumor s, it appears that starting and stopping ages for screening of 40 and 80 years, respectively, seem realistic. An increased screening frequen cy results in a larger reduction of breast cancer mortality. This redu ction is significant for ages between 40 and 51 years but only margina l for ages above 70 years. High resolution screening, i.e., the detect ion of tumors at smaller size, results in a larger benefit but does no t indicate a younger age for starting of screening. The average glandu lar dose per screening session does only influence the risks of screen ing. As separate risk and benefit results are presented, a change in a verage glandular dose on the total effect of screening can easily be c alculated. (C) 1997 Elsevier Science Ireland Ltd.