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

16 Screening for Colorectal Cancer KCE reports vol.45
1 GENERAL INTRODUCTION TO CANCER
SCREENING
1.1 DEFINITION OF SCREENING
In medicine, screening is typically a strategy used to identify disease in a
primarily unsuspecting population. Unlike in curative medicine, in screening a
test or intervention is performed on individuals without any known clinical
indication of disease. The intention is to identify disease in an earlier stage, thus
enabling earlier intervention and management in the hope to reduce mortality
and suffering from disease.
However, there remains a certain overlap with pre-emptive searching for
disease in suspected population subgroups at more than average risk and
surveillance of those with confirmed disease or genetic predisposition, as we
will discuss further on.
1.2 PRINCIPLES OF SCREENING
The principles underlying an effective screening intervention were originally
developed by Wilson and Jungner in 1968 1, and these are summarized below:
1. The condition should be an important health problem for the
individual and community.
2. There should be an accepted treatment or useful intervention
for patients with the disease.
3. Facilities for diagnosis and treatment should be available.
4. There should be a recognizable latent or early symptomatic
stage.
5. There should be a suitable test or examination.
6. The test should be acceptable to the population.
7. The natural history of the condition, including development for
latent to declared disease, should be adequately understood.
8. There should be an agreed policy for referring for further
examination and whom to treat as patients.
9. The cost of case-finding (including diagnosis and treatment of
patients diagnosed) should be economically balanced in relation
to possible expenditure on medical care as a whole.
10. Case finding should be a continuing process and not a "once and
for all" project.
The essence of these principles is that the target disease process should be a
common problem that has a better outcome when treated at an early stage, and
that the test employed is acceptable and sufficiently sensitive, specific, and
inexpensive to be cost-effective.
Although these original principles remain largely valid, other considerations are
to be made. In its Report on the Dutch consensus development meeting for
implementation and further development of population screening for colorectal
cancer based on FOBT 2, the Dutch National Health Council 3 extended the