European guidelines on colorectal cancer screening and diagnosis

Should a letter including the self-sampling stool-based test vs. a letter alone (with instructions on how to obtain the kit) be used for inviting asymptomatic adults to an organised, population-based, colorectal cancer screening programme?

The WG judged that the balance between desirable and undesirable effects probably favours using a letter including the self-sampling FIT kit, that there is probably no important uncertainty or variability in how much people value the main outcomes, and that the intervention is probably cost-effective and acceptable.

The evidence shows that with a letter including the self-sampling FIT kit, there might be an increase in participation, which would translate into a small reduction in colorectal cancer mortality (21 deaths fewer per 100,000 people screened) and incidence (65 cases fewer per 100,000 people screened). The overall certainty in the evidence is low because of the inconsistency in results, which leads to some uncertainty about the magnitude of the effect. This inconsistency arises partly from differences in how studies compared access methods to the FIT kit and from focusing primarily on responders. The Working Group also considered that using a letter including the self-sampling FIT kit will probably increase equity and is probably feasible to implement.

This recommendation is conditional, as its applicability depends on the specific context and setting in which it is implemented. The intervention is aimed at increasing the accessibility by mailing the FIT kit directly, thereby reducing the logistical barriers associated with picking up the kit. However, its effectiveness is conditional on the existing system for obtaining the kit. The importance of reducing logistical barriers is context-dependent; as such barriers may vary in significance depending on the local circumstances. Programmes can implement this intervention in different ways, and the need to address logistical barriers should be assessed locally, considering organisational factors and the relevance of these barriers in the given context.

The ECICC Working Group agreed on this recommendation by consensus. 

The WG made the following considerations regarding vulnerable populations:

• There might be challenges in delivering the kit to certain minority groups;
• Mailing the kit reduces the opportunity to provide information via direct contact to people with socioeconomic disadvantages;
• Mailing the kit reduces the logistical burden to perform the exam for individuals with mobility impairments or other disabilities that make it difficult to collect the kit in person.

The WG noted that implementing this intervention would be more appropriate in those countries with a well organised screening programme already in place, with an up-to-date database (e.g. ability to exclude the people not eligible for the screening round as having undergone colonoscopy or FIT).

To identify the eligible population to invite see the recommendations made by the ECICC WG on screening ages and frequencies, in the context of an organised, population-based screening programme.

The intervention should be monitored at country level.

The impact of mailing the kit on inequalities (geographical, gender, age and other demographic characteristics of the population) can be monitored during the implementation.

• Impact on uptake across different socioeconomic groups;
• Budget impact assessments.