Four procedures in use: fecal occult blood test, sigmoidoscopy, colonoscopy and contrast barium enema.
For the general population age 50 years is the age recommended for screening to begin.
ACS now recommending screening begin at age 45 because colorectal cancer recently has been developing in younger aged patients.
Estimated that screening may reduce mortality from CRC by 40%.
By detecting Colorectal Cancer had a curable stage mortality can be reduced: patients with localized Colorectal Cancer have a 90% relative five-year survival, whereas rates for those with regional and distant disease is 71% and 14%, respectively demonstrating that earlier diagnosis can have a large impact on survival.
Prevention consists of periodic screening for pre-cancerous polyps with either a colonoscopy or a high sensitive stool-based test.
Sigmoidoscopy associated with reduced incidence and mortality from left-sided but not right sided cancers.
Colonoscopy is the predominant procedure for screening, its justification is still largely theoretical as yielding a greater detection of adenomatous polyps.
Colonoscopy is associated with a 40 to 69% decrease in the incidence of colorectal cancer and a 29 to 88% decrease in the risk of death from this cancer.
In a case controlled study from Canada colonoscopy was associated with a reduction in colorectal cancer mortality, but this reduction was limited to left-sided cancers with no reduction in right side cancers ( Baxter NN).
Observational studies indicated the association between colonoscopy and reduce colorectal cancer risk is limited to the distal colon: colonoscopy has therefore not yet been proven to be more effective than sigmoidoscopy (Brenner H, Singh H).
For high risk individuals age 40 is the age generally recommended for the starting age for screening.
Studies suggest African-Americans should begin screening at age 45 years.
Can decrease incidence of colorectal cancer and death owing to detection of precancerous lesions and malignancies at early stage.
Colonoscopy primary screening tool for colon cancer performed every 10 years beginning at age 50 years in average risk patients and at 40 years for populations at increased risk.
Current guidelines support lowering the age of screening in individuals with a family history of CRC to 10 years younger than the age of diagnosis of the family member or 40 years of age, whichever is lower.
Prevalence of advanced cancer detected during colonoscopic screening higher among men than women.
In a study of 50,148 the male sex was an independent predictor of advanced cancer (Regula).
Cost per year of a life saved about $50,000.
Screening for colorectal cancer (CRC) should begin at age 45 years instead of 50 years, as recommended in the current guideline, the US Preventive Services Task Force (USPSTF).
The recommendation is that all adults aged 45 to 75 years be screened for CRC.
U.S. Preventative Task Force (USPTF) recommended screening should stop at age 75 years.
Multitarget DNA testing in asymptomatic persons at average risk for colorectal cancer detects significantly more cancers than fecal immunochemical tests (FIT), but had more false positives (Imperiale TFAS et al).
DNA test includes molecular assays for KRAS mutations, aberrant ND RG4 and BMP3 methylation, and B-actin plus a hemoglobin immunoassay.
In the above study the sensitivity for detecting colorectal cancer was 92.3% with DNA TESTING VS 73.8% for FIT.
In the above study the sensitivity for detecting advanced precancerous lesions was 42.4% with DNA testing and 23.8% with FIT.
The rate of detection of polyps with high-grade dysplasia was 69.2% with DNA testing and 46.2% withFIT.
The number of persons who would be screened to detect one cancer was 154 with colonoscopy, 166 with DNA testing and 280 with FIT.