Globally, there are approximately 1.8 million newly diagnosed cases of colorectal cancer (CRC) and nearly 900,000 deaths each year.
population screening can effectively reduce mortality, the relative risk of CRC screening ranges from 0.67 to 0.88, depending on the form, frequency and sex of screening.
, however, most CRC patients who are generally screened also have symptoms.
in the UK, less than 10 per cent of CRCs are screened and the rest are determined only after symptoms appear.
In many countries, patients with symptoms are first treated in primary care (community care) services, where the likelihood of cancer is assessed primarily by a general practitioner (GP), while routine diagnostic examinations in secondary care are colonoscopy, with occasional CT imaging or capsule endoscopy.
Fecal immunochemical testing (FIT), a good option for CRC prevention, was introduced in primary care in the UK in 2017 as a way to misdiagnose low-risk patients with low-risk symptoms of potential colorectal cancer, but there is little evidence of basic care.
health care providers in the south-west of England (population 4 million) were involved in the study, using a histogram of quantitative test results for fecal immunochemical tests.
from 1 June 2018 to 31 December 2018, a total of 3,890 patients aged ≥50 had low-risk symptoms of colorectal cancer and received a FIT.
threshold for fecal diagnosis is 10 μgHb/g, defined as positive.
results showed that 618 (15.9%) patients tested positive and 458 (74.1%) patients were urgently referred to a specialist lower digestive tract (GI) service within three months.
43 of them were diagnosed with colorectal cancer within 12 months.
3272 patients tested negative for FIT-tested patients and a further 3272 patients in the diagnostic flowchart, and 324 (9.9%) patients had an emergency referral within three months.
eight people were diagnosed with colorectal cancer in 12 months.
results showed a positive prediction of 7.0% and a negative prediction of 99.8%.
sensitivity was 84.3 per cent and specificity was 85.0 per cent.
ALC area (area under the ROC curve) is 0.92.
threshold of 37 μgHb/g in feces can identify individual patients with a 3% risk of cancer.
, the results showed that FIT did well in classifying patients with low-risk symptoms of colorectal cancer in primary care.