May 23, 2018
Screening for colorectal cancer in people with a family history: benefit for under 55-year-olds is still unclear
Additional studies found in search update – but the results provided no answers to the study questions
Between the age of 50 and 54 years, all statutory health insurance fund members in Germany are entitled to immunological faecal occult blood testing and, in the case of a suspicious result, to a colonoscopy. From the age of 55 years onwards, members of the health insurance funds can choose between faecal occult blood testing every two years or two colonoscopies at least ten years apart.
The Federal Joint Committee (G-BA) is considering to abolish these fixed age limits for this screening. As a result, testing could be offered earlier or more often in groups of people at risk (risk-adapted screening).
Focus on people under 55 years of age with a family history of colorectal cancer
The G-BA therefore commissioned the German Institute for Quality and Efficiency in Health Care (IQWiG) to update a report from the year 2013 in an accelerated process known as “rapid report” on the following question: Can people under 55 years of age with a family history of colorectal cancer benefit from a screening test?
The IQWiG researchers identified two further studies that are principally relevant for the research question. These studies provided no answers to the research question of the rapid report, however: Due to a lack of new findings, benefit or harm of the screening for people under the age of 55 years with a family history remain unclear.
Family history of colorectal cancer increases risk
Based on the available studies, only the question regarding family risk could be sufficiently answered in IQWiG’s final report from 2013: Under 55-year-olds with at least one first-degree relative with colorectal cancer have a 1.7 to 4.1 times higher risk of also developing colorectal cancer than people of the same age without a family history of colorectal cancer.
Two new studies on the comparison of screening procedures
The current search found two studies investigating whether colorectal cancer and advanced adenoma are less common in people with a family history of colorectal cancer if certain screening procedures are used: The FACTS study investigated whether it makes a difference if colonoscopy is repeated after three years or only after six years (surveillance interval). The COLONFAM study compared colonoscopy with immunological faecal occult blood testing. Due to a lack of conclusive results, these studies could not answer the study questions.
Benefit of risk-adapted screening remains unclear
Like the 2013 final report, the current rapid report therefore concluded that the benefit of screening for under 55-year-olds with a family history of colorectal cancer is unclear. A potential harm from screening tests also remains unclear: For instance, harm can be caused by people being wrongly allocated to the risk group, causing unnecessary psychological stress.
In view of this data situation, it must be carefully considered whether and how a risk-adapted screening strategy should be introduced.