From observational studies, it is know that the risk of developing colorectal cancer after polyp removal is lower if the patients adheres to surveillance recommendations. However, colonoscopy is burdensome for patients and colonoscopy availability is limited in many parts of the world. In addition, more than half of surveillance colonoscopies are without any findings. The trial investigates whether surveillance using fecal testing for blod is as good as colonoscopy after removal of colorectal polyps.

Colorectal cancer is the third most common cancer in the world and develops from benign colorectal polyps. Colonoscopy with polyp removal reduces colorectal cancer incidence and mortality. Patients who have had polyps removed are at increased risk for metachronous polyps and subsequent cancer and are referred to colonoscopic surveillance at regular intervals, the first one usually scheduled three years after polypectomy. Today, these comprise 15-25% of all colonoscopies, but in >85%, no high-risk pathology is found. Thus, post-polypectomy surveillance consumes major resources without benefit to the patients, and these resources are much needed for colonoscopies due to other indications in an aging population. Additionally, colonoscopy requires burdensome bowel-cleansing, discomfort during the examination, absenteeism from work and sometimes need for an escort. Severe complications like bleeding and perforation may occur. Overdiagnosis and overtreatment of benign lesions occur in a large proportion of examinations as most polyps will never develop into colorectal cancer, even if left untreated.

Sensitive fecal occult blood tests (FIT) have been developed that may detect colorectal cancer with the same sensitivity as colonoscopy. The test is cheap, is easily distributed by mail and may be performed at home. If the test detects blood, colonoscopy is indicated. FIT has been used in colorectal screening program for years, but has not yet been thoroughly investigated for post-polypectomy surveillance purposes.

The trial is a pragmatic non-inferiority randomized trial in which patients who are eligible for 3-year colonoscopic surveillance are offered either colonoscopy (standard care) or FIT followed by a colonoscopy in case of a positive test result (Figure 1). FIT may decrease colonoscopy surveillance demand by > 50%, which equals a cost saving of almost 30,000,000 Norwegian kroner annually. By proposing FIT for post-polypectomy surveillance, the trial introduce decentralized and personalized medical follow-up of these patients, and at the same time reduce work-absenteeism, patient discomfort, risk of complications and importantly: overdiagnosis and overtreatment of benign colorectal lesions.

Inclusion Criteria:

• High-quality baseline colonoscopy with adequat cleansing and cecal intubation
• Remocval of at least one advanced adenoma
• Clean colon (all polyps removed)
• Signed informed consent

Exclusion Criteria:

• Colorectal cancer
• History of surgical colon resection for any reason
• Genetic cancer syndrome (adenomatous or serrated polyposis syndrome; Lynch or Lynch-like syndrome)
• ≥ 10 adenomas at baseline colonoscopy (cumulative)
• History of advanced serrated lesion, defined as SSL≥ 10mm or with dysplasia
• Inflammatory bowel disease
• On-going palliative care for any reason