A randomised study of screening for colorectal cancer using faecal occult blood testing: results after 13 years and seven biennial screening rounds.

Area of Science:

• Oncology
• Preventive Medicine
• Gastroenterology

Background:

• Colorectal cancer (CRC) mortality can be reduced through repeated screening with faecal occult blood tests.
• This study presents findings from a long-term, ongoing randomized trial evaluating CRC screening.
• The Hemoccult-II test has been a focus in multiple trials demonstrating screening efficacy.

Purpose of the Study:

• To assess the reduction in colorectal cancer (CRC) mortality after seven rounds of biennial screening.
• To investigate the impact of screening compliance on CRC-specific mortality.
• To evaluate the long-term effectiveness of the Hemoccult-II screening program.

Main Methods:

• A randomized trial involving 30,967 participants screened biennially with Hemoccult-II and 30,966 controls, aged 45-75.
• Colonoscopy was offered for positive Hemoccult-II tests; participants completing the first round were invited for subsequent screenings.
• The primary endpoint was death from colorectal cancer, with 10-year results analyzed.

Main Results:

• CRC mortality was significantly lower in the screening group (relative risk [RR] 0.82), with a reduction to RR < 0.70 after seven rounds.
• Mortality reduction was most pronounced for cancers located above the sigmoid colon.
• Non-responders and those with inconsistent screening adherence showed an increased risk of CRC death.

Conclusions:

• Biennial screening with Hemoccult-II demonstrates sustained reduction in colorectal cancer (CRC) mortality.
• High adherence to the screening program is associated with a significantly lower CRC mortality risk (RR < 0.70).
• The findings support the expansion of population-based screening programs for CRC, with consideration for additional screening methods for distal colorectal cancers.