Report in English with a Dutch summary (KCE reports 45A)

KCE reports vol.45 Screening for Colorectal Cancer: Appendices 151
years in individuals who have already been screened before, or in people
entering the screening program can be detected. Therefore, the number of
colonoscopies needed will be lower in the subsequent years.
For the group 50- to 74-year-olds, the total budget impact of a biennial CRC
screening program is 33,1 million per year for the GP system and 18,4 million
per year for the mailing system in the second screening round. Due to the
high fixed costs associated with the screening campaign, the difference in
expected total costs between the first and second screening round is not very
high. The number of colorectal cancers detected, however, is lower in the
second round (707 in the second round compared to 989 in the first round). As
a consequence, the average cost per colorectal cancer detected is much higher
in the second round than in the first round. The cost per colorectal cancer
detected is 50.271 in the GP system and 29.488 in the mailing system.
Restricting the screening program to people between 55 and 75 years of age
would lower the budget impact to 25,3 million per year in the GP system and
14,3 million per year in the mailing system, but slightly increase the cost per
colorectal cancer detected. This is due to the fact that the decrease in number
of CRC detected is relatively larger than the decrease in the budget impact. The
cost per CRC detected in this age group is 51.390 in the GP system and
30.606 in the mailing system. It should be understood, however, that in our
model we used similar positivity rates and detection rates of CRC and
adenomata for this older age group, while in real live, these rates are likely to
be higher in older age groups. As a consequence, the actual cost per CRC
detected in 55- to 74-year-olds might be lower and hence the difference
between the costs per CRC detected of the two strategies smaller.
8.2.1.3 Comparing screening strategies in different age groups
From a comparison between the target populations defined by age, we can
conclude that screening 55- to 74-year-olds is expected to be less expensive for
the government but also less effective in detecting colorectal cancers (table 34).
The expected incremental cost of screening 50- to 74-year-olds as compared to
55- to 74-year-olds in the GP system is 8,2 million per year in the first
screening round. This would lead to an additional 248 CRC detected. In the
mailing system, the expected incremental cost is 4,5 million per year for the
same additional number of CRC detected. The incremental cost, from a
governmental point of view, of detecting one additional colorectal cancer in the
first screening round would be 33.053 in the GP system and 18.157 in the
mailing system if age limits were extended from 55-75 to 50-75.
In subsequent screening rounds, the expected incremental cost of screening 50-
to 74-year-olds as compared to screening only 55- to 74-year-olds is 7,8 million
per year in the GP system and 4,1 million in the mailing system. This would
lead to an additional 177 CRCs detected in both systems. The incremental cost
per CRC detected of screening 50- to 74-year olds as compared to screening
55- to 74-year olds would be 44.136 in the GP system and 23.179 in the
mailing system. The incremental cost, effectiveness and cost-effectiveness
figures are presented in table 34.