Table 2.

Example of application of new criteria to screening for genetic susceptibility to colorectal cancer

Crossroads 99 criteria	Testing for susceptibility to colorectal cancer	Met by new criteria
Knowledge of population and disease
Burden of target disease should be important	Colorectal cancer is third commonest malignancy in United Kingdom, incidence is increasing	Yes
Ability to identify target population or population at risk	Amsterdam criteria are generally accepted; further research on accuracy of criteria is required; no large series of patients fulfilling Amsterdam criteria has mutation detection rate >70%	Partially
Considerable level of risk or latent or preclinical phase	Lifetime risk of colorectal cancer in those with two first degree relatives is 1 in 6; in those with autosomal dominant pedigree it is 1 in 2 (population risk is 1 in 50)	Yes
Natural course (from susceptibility to precursor, early disease, and advanced disease) should be adequately understood	Natural course from premalignant adenomatous polyps to malignant polyps is understood; whether progression is different in those with different mutations needs to be more clearly established	Partially
Feasibility of screening procedures
Suitable test or examination	Known mutations can be screened for, familial testing protocols are required; acceptability in population is being assessed	Partially
Entire screening procedure acceptable to population	Acceptability of familial assessment and mutation testing in general population is not yet established	No
Screening should be continuing process and encompass all elements of screening procedures	Complete range of services required for screening (education, counselling, support) not in place	No
Interventions and follow up
Interventions that have physical, psychological, and social net benefit available	Surveillance and treatment available but balance of physical, psychological, and social benefits not established; interventions such as chemoprevention are being evaluated	No
Facilities for adequate surveillance, prevention, treatment, education, counselling, and social support available	Level of services required and infrastructure not in place	No
Consensus on accepted management for those with positive test results	Emerging consensus on management of mutation carriers	Partially
System issues
Costs should be balanced in economic, psychological, social, and medical terms and with healthcare expenditure as whole	Cost effectiveness in economic, psychological, social, and medical terms not established	No
Appropriate screening services accessible to entire population without adverse consequences for non-participants	Familial assessment and testing available only in specialised centres	No
Appropriate confidentiality procedures and antidiscrimination provisions for participants and non-participants	Appropriate procedures and provisions not yet completely studied or established	No