In this study, researchers from Japan evaluated colorectal cancer screening using fecal occult blood testing (FOBT) for the prevention of advanced cancers.
The research team conducted their case-control study in areas where an annual screening program has been offered to all inhabitants aged 40 years or over.
They included 357 consecutive patients clinically diagnosed with advanced colorectal cancer, or a tumor invading the muscularis propriae or deeper (T2-T4).
|Odds ratio of developing colorectal cancer for patients screened within 3 years of diagnosis was 0.54.|
|British Journal of Cancer|
The team matched the patients with controls who were selected for gender, age, residential area and exposure status to screening within 1 year before case diagnosis.
The researchers then calculated the odds ratios (ORs) of developing advanced cancer using conditional logistic regression analyses.
The team found that the OR for those screened within 3 years of diagnosis was 0.54, compared with patients who were not screened.
They also determined that the ORs were lower for rectum than for colon.
For those patients screened within the last 3 years, the OR of developing advanced cancer in the rectum was 0.32.
Dr Nakajima's team concluded, "A screening program with immunochemical FOBT can be effective for prevention of advanced colorectal cancer".
"Risk reduction appears to be larger for rectal than for colon cancer".