As tests evolve and costs of cancer care rise: reappraising stool-based screening for colorectal neoplasia. Screening for colorectal cancer: updated evidence report and systematic review for the US Preventive Services Task Force. Our search identified 3026 records (Figure 1). Understanding why some people are willing to be screened but do not follow up can lead to improvements in the effectiveness of the screening process.. Effectiveness: According to the USPSTF report, when the patient has colon cancer, the test is likely to indicate its presence 62% to 79% of the time. DG; PRISMA Group. Traces of blood in your poo can be caused by other medical conditions and doesn't necessarily mean you have cancer. It may not seem like 7 years is a huge difference, but the colorectal cancer prevalence from the under 45 age bracket is much lower than 50+. The greatest concern regarding applicability was due to the FIT and the reference standard used. The rate of early-stage disease was also higher in this group (51.3%) than in the group 2 (45.5%). But because you use FIT every year, 10 . Experts generally recommend that people repeat this test every 1 to 2 years. Study selection methods. MEDLINE, EMBASE, Cochrane Library, and gray literature sources through August 2016. So it tends to be more accurate and have fewer false positive results than other tests. The type of FIT used and cutoff threshold were the most important contributors to the heterogeneity of results. Subgroup analyses indicated that FIT cutoff values between 15- and 25-g/g feces provided the best combination of sensitivity and specificity for the diagnosis of CRC (93% and 94%, respectively). Respective values for AN varied from 37% to 56% for sensitivity and 92 to 98% for specificity. Cloud VA Health Care System would be predicted to reduce the reflex to colonoscopy, based only on . Conclusions and Relevance The study points to the importance of more closely monitoring people who do not follow recommendations after a positive FIT result, said Erica Breslau, Ph.D., M.P.H., of NCIs Healthcare Delivery Research Program, who also was not involved in the study. Schnemann H, Brozek J, Guyatt G, Oxman A, ed; GRADE Working Group. // US Department of Health & Human Services Agency for Healthcare Research and Quality. JS, Van Der Hulst Finally, 3 studies were prone to differential verification bias as they invited participants with negative FIT results to undergo a delayed colonoscopy as the reference standard.26,34,37 Most analyses had high heterogeneity and wide confidence intervals of pooled estimates, hence raising concerns about the reliability of our findings. The positive test result Bayesian multiplier (here, 6.8) raised our estimate of the probability of colon cancer from 0.7% to 5%, supporting getting the colonoscopy, which turned out to be negative (no cancer detected). Z, Birkenfeld M, Twelve studies met the inclusion criteria and were included in the systematic review.26-37, The main characteristics of included studies are displayed in Table 1. D, Liberati They said, it just states either negative or positive for cancer. Heterogeneity and small sample sizes undermine the quality and validity of these findings. Quiz Ref IDColorectal cancer (CRC) is the third most common type of cancer in men and the second most common in women worldwide.1 Early detection of CRC through widely applied screening programs has proven to be effective in reduction of cancer-related mortality. Two authors (A.K. Cologuard found 93 percent of the cancers detected by screening colonoscopy. AH. Can miss many polyps and some cancers. We included studies that reported the diagnostic accuracy of FIT for CRC or advanced neoplasia (CRC, or adenomas 10 mm or with 25% villous component and/or high-grade dysplasia) in asymptomatic adults with family history of CRC or personal history of CRC or advanced adenomas and used colonoscopy or follow-up as the reference standard. In a pragmatic trial34 assessing the effectiveness of a diagnostic strategy using annual FIT for 3 years for detection of AN vs colonoscopy in asymptomatic patients with a family history of CRC, annual FIT was as good as colonoscopy for AN; however, it missed almost 40% of advanced adenomas. Fecal immunochemical test (FIT). Dr. Zorzis team found that people in the no-colonoscopy group were at higher risk of dying from all causes, not just from colorectal cancer. Moher PS, Bostock A prospective, controlled, feasibility study. Amersi O, De Chiara We explored robustness of our findings by means of a series of prespecified sensitivity analyses, excluding studies at high or unclear risk of bias, studies recruiting patients with prior history of CRC or advanced adenomas (potential for spectrum bias),25 or studies that used delayed colonoscopy in patients with FIT-negative results as reference standard (potential for differential reference bias). M, Hernndez-Guerra et al. The program offers free FIT testing once every 2 years to people 5069 years old. We estimated whether non-compliance with colonoscopy after a positive FIT is associated with increased CRC incidence and mortality. the bowel cancer screening test detects most (up to 85%) but not all bowel cancers; This is why it's important to do the screening test every 2 years between 50 and 74. Cost. Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. Both studies focused on a single screening episode analysis, which cannot account for the potential contribution of repeated FIT applications to overall screening effectiveness, they added. Bowel cancer (colorectal cancer, CRC) is the second most common cause of cancer death in the UK, accounting for 10% of all cancer deaths in 2017. Given the safety, simplicity, low cost, and minimal discomfort of FIT, it is a viable alternative screening strategy for patients at increased risk for CRC. CA. About 60% of the time, they'll find nothing; about 35%, a polyp; about 4%, a very early cancer; about 1% a less early cancer. et al. The positive result could be caused by a stomach ulcer, hemorrhoids, other inflammation. Are fit tests accurate? M, Ko Studies have shown that this type of test detects cancer with 92 percent accuracy. This test uses antibodies that specifically react with a blood protein in the stool. However, 14 percent of tests deliver false positive resultsfar higher than the FIT test. FIT LR+ is more than 10 and LR is less than 0.1, hence having a significant effect on pretest probabilities and providing strong evidence for the presence or absence of CRC, respectively.47 In a population with a prevalence of CRC equal to 0.8%, a negative result decreases the posttest probability to less than 0.1%, whereas a positive result increases the posttest probability to 8.0%, which crosses a conventional threshold of risk to perform colonoscopy. It's also possible for the test to miss some cancers, which is called a false-negative result. FIT works in a similar way to the current test by detecting hidden traces of blood in poo that could indicate bowel cancer or pre-cancerous growths known as polyps. S, ed. People in this group were more likely to have their cancer detected only after symptoms appeared, when the cancer was more advanced. L, U.S. 2022 American Association for Clinical Chemistry. P, Hazazi It is also important to establish optimal thresholds, test cutoff values, and number and frequency of FIT samples.10 Our results also should prompt randomized trials to assess the implementation of FIT either alone or in combination with other screening procedures into screening strategies for increased-risk individuals. et al. In this meta-analysis, FIT has high overall diagnostic accuracy for CRC and moderate accuracy for advanced neoplasia. A FIT kit is an alternative to a colonoscopy. Dominitz Washington, DC 20001 The primary outcome was the diagnostic performance of FIT for detecting CRC or AN. Inc32,37; OC-light, Eiken Chemical28; and HemeSelect, Smith-Kline Diagnostics30). The first stool tests developed were based on the finding of occult, or hidden, blood. EG, Bent FIT testing is recommended annually, and Cologuard every three years if testing is negative, but positive test results require a follow-up with colonoscopy. Oort JL, Akl Medicines and foods do not interfere with the test. Surveillance after polypectomy and after resection of colorectal cancer. Further research is needed to assess whether this relationship . FIT has high overall diagnostic accuracy for CRC in increased-risk individuals. FIT has now supplanted gFOBT in the pathway for symptomatic patients. However, in 3 studies, the time interval between FIT and colonoscopy depended on the FIT result, such that colonoscopy was delayed more so in those with a negative FIT.26,34,37. M, Parra-Blanco DA. et al. For the study, Manuel Zorzi, M.D., M.Sc., of the Veneto Tumour Registry in Padua, Italy, and his colleagues, examined the medical records of participants in a regional colorectal screening program who took a FIT test between January 1, 2004, and September 30, 2017. From these findings, they concluded that a periodic FIT was an accurate test in people with average CRC risk. Finally, we graded the quality of the body of evidence using appropriate methodology (GRADE). et al. FIT detects 74% of colon cancers and 24% of large colorectal polyps. Heterogeneity and wide confidence intervals limit the trustworthiness of our findings. FIT (Fecal Immunochemical Test) is a stool test used to look for possible signs of colorectal cancer. There are two types of stool tests for colon cancer. In recent years fecal immunochemical tests (FITs) have been offered as a primary screening test for colorectal cancer (CRC) in a growing number of countries. by Elia Ben-Ari, December 22, 2022, Over that time, about 2 percent of the people, about 2,700 of them, had positive tests. They used Union for International Cancer Control (UICC) stage and T stage (infiltration) to measure sensitivity. JPT, Green Can have false-positive test results. independently evaluated the quality of included studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool.15 Discrepancies were resolved by consensus. P. metandi: meta-analysis of diagnostic accuracy using hierarchical logistic regression. No pre-test diet or medication changes needed. Free phone consultations with a registered nurse is available for people who test positive for a medical condition using one of LetsGetChecked tests. To assess the diagnostic accuracy of FIT for CRC or advanced neoplasia (AN) in asymptomatic patients at above-average risk. DG. Acquisition, analysis, or interpretation of data: All authors. The ongoing NCI-funded PROSPR program aims to better understand how to improve the cancer screening process and reduce disparities in colorectal and other cancer screening in community health care settings in the United States. FIT only detects human blood from the lower intestines. Repeat use of FIT and higher compliance to screening schedules48 could potentially counterbalance the superior accuracy of colonoscopy in the diagnosis of AN. EA, Alonso-Coello For studies using multiple-sample FIT, positivity was rated based on the highest amount of fecal Hb measured in patient samples. NC. Not a virtual colonoscopy, or another stool test, or another scan of some sortyou need a real optical colonoscopy. eFigure 2. LM, Rooney LA, Pooled estimates of sensitivity and specificity for CRC were 93% (95% CI, 53%-99%) and 91% (95% CI, 89%-92%), yielding a positive likelihood ratio (LR+) of 10.30 (95% CI, 7.7-13.9) and a negative likelihood ratio (LR) of 0.08 (95% CI, 0.01-0.75). The Bayesian estimate from the positive test result is almost seven times the assumed 0.7% prevalence. Carroll In the study, Imperiale and his colleagues determined that when the FIT was set to be more sensitive, the test caught 95 percent of cancers, but resulted in 10 percent false positives. It has recently been suggested that fecal immunochemical testing (FIT) could be used for population-based screening owing to its high accuracy and adherence.7-9 Previous systematic reviews and meta-analyses have assessed the performance of FIT in average-risk populations.10,11 However, the potential role of FIT for screening of individuals at increased risk for CRC has not yet been fully elucidated. The DNA test is 92% effective at detecting cancers. It tests for hidden blood in the stool, which can be an early sign of cancer. Y, Liu Serum sCD26 for colorectal cancer screening in family-risk individuals: comparison with faecal immunochemical test. FIT is currently FDA-approved for spontaneous stool and DRE, however, samples are not commonly obtained by DRE. Another study examined the merits of colonoscopy in patients with negative FIT tests in a large program that conducted annual screening. I didn't follow that and put myself through agony for weeks. We synthesized data regardless of the FIT cutoff used. Some people may have had other illnesses that precluded them from having a colonoscopy or made them feel that they were more likely to die from causes other than colorectal cancer, he explained. For example, peoples fears about the preparation for colonoscopy continue to be a major barrier. B, Castro Grading quality of evidence and strength of recommendations in clinical practice guidelines: part 2 of 3. the GRADE approach to grading quality of evidence about diagnostic tests and strategies. Random comparison of guaiac and immunochemical fecal occult blood tests for colorectal cancer in a screening population. . A positive FIT test is concerning. The pooled sensitivity and specificity for AN were 48% (95% CI, 39%-57%) and 93% (95% CI, 91%-94%), yielding an LR+ of 6.5 (95% CI, 5.0-8.5) and an LR of 0.57 (95% CI, 0.48-0.67). The low incidence of colorectal cancer after that was likely due to the early detection of cancers and the removal of precancerous lesions during colonoscopy, Dr. Breslau explained. Although this looks like a clear advantage for fecal DNA (60 of 65 cancers detected compared . A hierarchical regression approach to meta-analysis of diagnostic test accuracy evaluations. These data indicate that participants who begin screening at the . Stool samples collected at home are sent in for analysis. The latest US Preventive Services Task Force recommendations for colorectal screening support that the best screening test is the one that gets done, and that the ultimate goal of screening strategies is maximization of screening uptake to reduce CRC mortality.45, Although our results verify the diagnostic accuracy of FIT for CRC in individuals at increased risk, this body of evidence is limited by a relatively small sample size. Diagnostic studies evaluating the accuracy of FIT for CRC or AN in patients with a personal or familial history of CRC using colonoscopy as the reference standard. E, Nicols-Prez However, FIT positivity rates and positive predictive value (PPV) can vary substantially, with false-positive (FP) results adding to colonoscopy burden without improving cancer detection. Colonoscopy-controlled intra-individual comparisons to screen relevant neoplasia: faecal immunochemical test vs. guaiac-based faecal occult blood test. Terms of Use| Positive and negative predictive values were 43.8% and 94.0%, respectively. TR, and P.P.) 1 Between 2015 and 2017, there were around 16,300 CRC deaths in the UK every year, equivalent to 45 deaths every day. FIT is the dominant screening test for colorectal cancer in most economically advanced countries, and the results support the accuracy of widespread periodic FIT screening, they added. I, Cubiella Question Colonoscopy will be needed if abnormal. Vleugels Purpose of a Cologuard Test. JJ, Altman Reasons for participation and nonparticipation in colorectal cancer screening: a randomized trial of colonoscopy and CT colonography. People with a positive FIT test result are advised to have a colonoscopy to investigate the cause of the bleeding because a FIT test alone cannot diagnose cancer. The area under the ROC (AUC) for diagnosis of CRC and AN was 0.93 (95% CI, 0.90-0.95) and 0.86 (95% CI, 0.83-0.89), respectively (eFigure 4 in the Supplement). Whiting H, The Cologuard test has a 13% false-positive rate, which means 1 in 10 positive tests will incorrectly identify cancer or polyps. Such a strategy is associated with higher cost, lower adherence, and higher risk for rare, but serious, complications.2-6. The study included 111,423 people who had a positive FIT test, of whom 88,013 people had a follow-up colonoscopy as part of the program (colonoscopy group) and 23,410 did not (no-colonoscopy group). Respective values for AN were sensitivity, 47% (95% CI, 37%-58%); specificity, 93% (95% CI, 91%-95%); LR+, 6.90 (95% CI, 4.90-9.70); and LR, 0.56 (95% CI, 0.46-0.69). RM, Whiting Nevertheless, all included studies evaluated 1-time application of the test, and results could not be transferred to repeat screening programs. Subgroup analyses indicated that FIT cutoff values between 15- and 25-g/g feces provided the best combination of sensitivity and specificity for the diagnosis of CRC (93% and 94%, respectively). Cologuard is one of six approved methods for colon cancer screening in the United States, including one of three stool-based tests.
