First results from the National Bowel Cancer Screening Program in the United Kingdom found significantly more colorectal cancers in early, curable stages than in the years before the program began.
Nearly half of the cancers found during screening were stage I (Dukes A), while previously only 1 in 10 were diagnosed at that earliest stage.
However, in another analysis of the pilot NHS NBCSP efforts, a significant percentage of patients who had cancer found on screening, believed to be without symptoms of colon or rectal cancer, recognized and reported symptoms when asked before their follow-up colonoscopies.
As part of the national bowel cancer screening program that began in England in 2006, the Wolverhampton Bowel Cancer Screening Centre sent over 108,000 fecal occult blood test (FOBT) kits to everyone in their target area between ages 60 and 69. About half (51.6 percent) were returned .
As a result 1,039 colonoscopies were performed and 106 cancers discovered.
A research team compared the cancers found during screening to a control group of 256 colorectal cancers diagnosed without screening. They found:
- Stage 1 (Dukes A): 45.6 percent with screening, 10.1 percent in control group before screening
- Stage II (Dukes B): 29.7 percent with screening, 50 percent in controls
- Stage III (Dukes C): 29.2 percent with screening, 36.3 percent in controls
- Stage IV (Dukes D): 3.8 percent with screening, 3.5 percent in controls
P. Ellu and the team from the Wolverhampton screening program concluded,
The 2-year data from the first English centre to start bowel cancer screening demonstrates significant downstaging of cancer, consistent with both the random controlled trial and pilot data.
Although initial results of the National Health Service National Bowel Cancer Screening Programme showed success in finding cancer earlier, an analysis of the NHS NBSCP pilot projects found that as many as 8 in 10 patients diagnosed with colorectal cancer through the screening program were already experiencing symptoms.
The pilot screening found 200 cancers: 28.5% were stage I, 35% stage II, 36.5 stage III.
Given a questionnaire about potential symptoms of colorectal cancer before their colonoscopies, some 81.5% reported experiencing gastrointestinal problems including:
- rectal bleeding in 47.7 percent
- change in bowel habits in 24 percent
- a feeling of difficulty during bowel movements in 36.5 percent
- peri-anal discomfort in 15.5 percent
- urgency in 25 percent,
- abdominal pain in 20,5 percent
- upper GI symptoms in 29 percent
In discussing the results C. Harmston and the team wrote,
This data suggests a high prevalence of significant symptoms amongst patients with screening-detected CRC. It is possible that these patients would have presented via routine colorectal services if the awareness of symptoms of colorectal cancer were increased.