Single flexible sigmoidoscopy screening associated with reduced colorectal cancer


A single flexible sigmoidoscopy screening between the ages of 55-64 years is associated with a lower level of colorectal cancer (CRC) incidence and mortality, according to a study published in the Journal of the National Cancer Institute.
Multiple randomized controlled trials have shown that fecal occult blood testing (FOBT) in CRC screening can reduce the mortality rate of patients diagnosed with CRC.
Observational studies and a prior, randomized trial from the U.K., known as SCORE have shown a reduction in incidence and mortality for cancer in the rectum and sigmoid colon (distal CRC) among patients who had undergone endoscopy, suggesting that the removal of adenomas at screening can provide long-term protection against the development of distal CRC.
The researchers, coordinated by Nereo Segnan, M.D., of the Epidemiology Unit at S. Giovanni University Hospital in Turin, Italy, sent a questionnaire  to a random population sample of men and women between the ages of 55-64 years.
Eligible interested responders were randomly assigned to either the control group (N= 17148 – no further contact) or intervention group (N=17144 – invitation for flexible sigmoidoscopy)
Flexible sigmoidoscopy was performed on 9,911 subjects, and of those, 9,387 (94.71%) were discharged, 55 (0.55%) were referred for surgery, 395 for follow-up surveillance colonoscopy, and the remaining 74 patients did not comply with the recommended total colonoscopy assessment.
The median follow-up period was 10.5 years for CRC incidence and 11.4 years for all-cause and CRC-specific mortality. During this period 557 people (including those detected at initial screening) were diagnosed with a CRC and 148 died of the disease.
The researchers found that in the intent-to-treat analysis, CRC incidence and mortality were reduced by 18% and 22%, respectively. CRC incidence was reduced by 31% among those who were screened (per –protocol analysis), and by 46% for advanced CRC cases. Furthermore, CRC mortality was statistically significantly reduced by 38% in screened subjects compared to the control group.
The reported findings, support the hypothesis that “Flexible sigmoidoscopy screening offered just once represents a safe and effective method for CRC screening and ensures a long lasting reduction of CRC risk.” According to the researchers, “A longer follow-up is needed to fully assess the impact on mortality and to estimate the duration of the protective effect.”
Find out more about community flexible sigmoidoscopy provision