First local results of the Finnish FIT-based colorectal cancer screening program - high yield, low complications

The aim of screening for colorectal cancer (CRC) is to find the cancer in its early stages, thereby improving the prognosis of cancer patients by preventing cancer-related deaths. In Finland, the national CRC screening program was initiated in 2022, with fecal immunochemical test (FIT) being the primary screening test. The FIT-threshold used was 25 µg hemoglobin/g feces. The aim of this retrospective study was to evaluate the results of the first screening round that was implemented by the wellbeing services county of Southwest Finland.

Participants were screened for CRC between March 1^st, 2022 and April 14^th, 2023. Participants aged 60-70 years had their health records scrutinized retrospectively.

Out of 36 397 FIT-invitees 23 388 (64%) returned a FIT-sample. 1407 (6%) subjects gave a FIT-positive stool sample of which 1118 (79%) attended the recommended screening colonoscopy. A total of 63 (6%) CRCs were found. 31 (49%) CRCs were classified as early stage I tumors, 12 (19%) of which were solely suitable for endoscopic treatment. Endoscopically removable adenomas were detected in 709 (63%) of the colonoscopies, which resulted in a recommendation of a 3-year follow-up colonoscopy for 427 (38%) cases. There were 3 (0.27%) acute polypectomy related complications and 5 (0.45%) late post-colonoscopy complications.

This is the first study to show the prevalence of CRC amongst participants of the newly implemented Finnish national CRC-screening program. Nearly half of the patients with CRC were diagnosed in the early stage. The adenoma detection rate was high.