NORCCAP - a randomized study on colorectal cancer screening

NORCCAP (Norwegian Colorectal Cancer Prevention) is a randomized study on screening for colorectal cancer (CRC) and adenomatous polyps (potential precursor lesions for colorectal cancer).

 Last updated: 2019.01.23


The project arose from an initiative made by the Norwegian Gastrointestinal Cancer Group (NGICG) and the Norwegian Cancer Society with funding from the Norwegian Cancer Society and the Ministry of Health and Social Affairs. The screening examinations were performed in Oslo and Telemark in 1999-2001. The first interim results from follow-up were published in June 2009. 10-year follow-up results are expected in 2014.

21,000 women and men between the age of 50 and 64, living in Oslo and Telemark, were randomly drawn from the population registry and offered a screening examination by flexible sigmoidoscopy (flexible endoscope for examination of the distal 50-60 cm of the large intestine). The rest of the population in this age range (n=79,000) constituted the control group. Half of the invitees were asked to deliver a stool sample for supplementary screening for blood in the feces (FOB-testing with an immunochemical test – FlexSure OBT®) and for research purposes to develop new stool-based screening methods. Blood samples were also drawn with a view to investigate folate-related gene polymorphisms and the risk of CRC.

Research results

So far, 55 original articles and 12 Ph.D theses have been published. Much of the research done has been of great value also to routine clinical activity. The quality assurance program in NORCCAP-I has developed further into a separate programme - Gastronet – a network for quality development in gastrointestinal endoscopy in Norway. Gastronet has become one of the national quality assurance programs of the Norwegian Directorate of Health and the official quality assurance platform for the Norwegian Gastroenterology Society.

Selected publications:

Rounge TB, Meisal R, Nordby JI, Ambur OH, de Lange T, Hoff G (2018)
Evaluating gut microbiota profiles from archived fecal samples
BMC Gastroenterol, 18 (1), 171
DOI 10.1186/s12876-018-0896-6, PubMed 30409123

Holme ØSchoen RESenore CSegnan NHoff GLøberg MBretthauer MAdami HOKalager M (2017). Effectiveness of flexible sigmoidoscopy screening in men and women and different age groups: pooled analysis of randomised trials BMJ356i6673. PubMed 28087510

Holme ØLøberg MKalager MBretthauer M, Hernán MAAas EEide TJSkovlund ESchneede JTveit KMHoff G (2014). Effect of flexible sigmoidoscopy screening on colorectal cancer incidence and mortality: a randomized clinical trialJAMA312 (6)606-15. PubMed 25117129

Holme ØBretthauer MEide TJLøberg EMGrzyb KLøberg MKalager MAdami HOKjellevold ØHoff G (2014). Long-term risk of colorectal cancer in individuals with serrated polypsGut64 (6)929-36. PubMed 25399542

Berstad PLøberg MLarsen IKKalager MHolme ØBotteri EBretthauer MHoff G (2014). Long-term lifestyle changes after colorectal cancer screening: randomised controlled trialGut64 (8)1268-76. PubMed 25183203

Hoff GGrotmol TSkovlund EBretthauer MNorwegian Colorectal Cancer Prevention Study Group (2009). Risk of colorectal cancer seven years after flexible sigmoidoscopy screening: randomised controlled trialBMJ338b1846. PubMed 19483252

Gondal GGrotmol THofstad BBretthauer MEide TJHoff G (2003). Grading of distal colorectal adenomas as predictors for proximal colonic neoplasia and choice of endoscope in population screening: experience from the Norwegian Colorectal Cancer Prevention study (NORCCAP)Gut52 (3)398-403. PubMed 12584223


More NORCCAP publications (updated 2017.04.07)