what percentage of positive fit tests are cancer?

SC, Ching 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 FIT identified patients with CRC with overall high sensitivity but missed nearly 50% of small (T1) and 32% of UICC stage I CRCs. 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. 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. 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. Y, Liu Colonoscopy is a good test for finding polyps or cancer in the bowel. et al. DA, McFarland The test should be done yearly. J, Altman What is a FIT? Having bowel cancer screening reduces your risk of dying from bowel cancer by at least 25% [footnote 1]. Only 3% of people with a positive FIT test have cancer (and less than 1% have advanced colorectal cancer), and remember that figure comes from studies whose participants were 50+. MA, Perdue Positive and negative predictive values were 7.7% and 99.9%, respectively. As patients with an abnormal result are at greater risk for precancerous polyps or cancer, it is important to attend to follow-up procedures. FN indicates false-negative results; FP, false-positive results; TN, true-negative results; TP, true-positive results. Tests and investigations for colorectal cancer screening. According to editorialists Senore and Zorzi, the study sheds new light on the tests sensitivity with respect to tumor characteristics. moderator 3rd September 2020. Complications of colonoscopy. A positive FIT is not a colorectal cancer diagnosis, but we do know that it can cause a great deal of anxiety. The greatest risk for bias occurred owing to flow and timing. Schnemann H, Brozek J, Guyatt G, Oxman A, ed; GRADE Working Group. TH, Purpose of a Cologuard Test. A sensitivity analysis excluding studies at high or unclear risk of bias verified robustness of our conclusions. Dominitz Cologuard is one of six approved methods for colon cancer screening in the United States, including one of three stool-based tests. During the period 2000-2017, the accumulated risk of a 'false positive' result was 16.2% adjusted for age, sex and type of test. But if it is cancer, finding it at . All Rights Reserved. This follow-up rate is comparable to some of the best follow-up rates in the United States and elsewhere, Dr. Corley said. We explored the robustness of our results in a post hoc sensitivity analysis including only studies in patients with family history of CRC that used quantitative FIT with a cut-off value of less than 25 g Hb/g feces. AZ, TR, Corley I didn't follow that and put myself through agony for weeks. P, Hazazi AACC uses cookies to ensure the best website experience. 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. . Abstract. JE, Halloran Terms of Use| Reasons for participation and nonparticipation in colorectal cancer screening: a randomized trial of colonoscopy and CT colonography. An abnormal result does not mean that cancer was found. The potential role of the fecal immunochemical test (FIT) for screening patients at increased risk for colorectal cancer (CRC) has not yet been elucidated. SC, Factors associated with false-positive and false-negative fecal immunochemical test results for colorectal cancer screening. The findings also highlight the need to identify opportunities to improve what is currently being done to ensure that people get the follow-up tests they need, Dr. Breslau said. 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.. We undertook a comprehensive search of multiple electronic databases and gray literature sources without imposing any restrictions based on language or publication type. Pooled test characteristics estimates for diagnosing CRC were sensitivity, 86% (95% CI, 31%-99%); specificity, 91% (95% CI, 89%-93%); LR+, 10.00 (95% CI, 5.80-17.5); and LR, 0.16 (95% CI, 0.02-1.48). In a study from the Netherlands, 4523 people (age range, 50-74) underwent FIT screening with OC-Sensor Micro; a hemoglobin concentration of 50 ng/mL was considered positive. Oort JK, Liles Corresponding Author: Anastasia Katsoula, MD, MSc, Hippokration General Hospital of Thessaloniki 54642, Thessaloniki, Greece (anastkatsoula@gmail.com). 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. et al; EPAGE II Study Group. Most of these were at high or unclear risk of bias due to suboptimal study design. Lee The initial sharp rise was expected, the researchers noted, due to colorectal cancer being found during follow-up colonoscopy. Brozek Finally, we could not calculate the pooled estimates in a sensitivity analysis including only studies at low risk of bias in patients with family history of CRC that used immediate colonoscopy due to limited data. Statistical analysis: Katsoula, Paschos, Haidich, Tsapas. CY. Levi Random comparison of guaiac and immunochemical fecal occult blood tests for colorectal cancer in a screening population. 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. FIT testing is recommended annually, and Cologuard every three years if testing is negative, but positive test results require a follow-up with colonoscopy. The pooled test characteristics for CRC were sensitivity, 97% (95% CI, 31%-100%); specificity, 91% (95% CI, 89%-93%); LR+, 10.80 (95% CI, 8.00-14.60); and LR, 0.04 (95% CI, 0.00-2.02). GM, Baron Acquisition, analysis, or interpretation of data: All authors. From these findings, they concluded that a periodic FIT was an accurate test in people with average CRC risk. How To Categorize Accounting Fees In Quickbooks , What Happened To Marcelo , Division Symbol Vs Slash , List Of High Risk Activities Air Force , Classical Guitar Luthiers Colorado , Chiong Sisters Conspiracy , Aerial Lineman Salary California , Johnny Jett Father Age , Batman Stunt Show Six . Z, Rozen How Fit Is FIT for Detecting Colorectal Cancer? Effect of Single-Dose Aspirin Prior to FIT on Colorectal Cancer Detection. Fecal immunochemical test (FIT) No direct risk to the colon. Carroll The pooled sensitivity was approximately 93% for CRC but much lower for AN (48%). Both studies appear in the Clinical Gastroenterology and Hepatology journal. Chemical and immunological testing for faecal occult blood in screening subjects at risk of familial colorectal cancer. To assess the diagnostic accuracy of FIT for CRC or advanced neoplasia (AN) in asymptomatic patients at above-average risk. Heterogeneity and wide confidence intervals limit the trustworthiness of our findings. Conclusions and Relevance Among patients with a positive fecal immunochemical test result, compared with follow-up colonoscopy at 8 to 30 days, follow-up after 10 months was associated with a higher risk of colorectal cancer and more advanced-stage disease at the time of diagnosis. First and foremost, a positive result on the Cologuard test means that you need to have a colonoscopy. AH. FIT only detects human blood from the lower intestines. 2023 American Medical Association. F, Amani In June, the U.S. Preventive Services Task . FJ, D, Hernndez-Guerra A hierarchical regression approach to meta-analysis of diagnostic test accuracy evaluations. A positive FIT test is concerning. independently evaluated the quality of included studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool.15 Discrepancies were resolved by consensus. Continuing without changing cookie settings assumes you consent to our use of cookies on this device. This study shows that even with a national health service that provides universal coverage, there are other barriers to obtaining care, Dr. Breslau said. M, Hernndez-Guerra Specifically, the investigators wanted to see if a colonoscopy identified any cancer missed by the FIT. et al. Beyond diagnostic accuracy: the clinical utility of diagnostic tests. Such factors include the patients personal circumstances (for example, access to transportation), whether they have health insurance, whether they can get timely access to colonoscopy, and whether they have had an adequate conversation with their doctor about screening. Eligible studies had to provide quantitative information on sensitivity and specificity or sufficient information to calculate them, and/or the area under the ROC curve (AUC/c statistic) for detection of CRC, AA or any advanced neoplasm (AN), and examine these outcomes for FIT alone and for the combination of FIT and a blood (serum/plasma) test. 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. Multiple factors can contribute to people not getting follow-up colonoscopy exams, both he and Dr. Breslau said. RJ, Bossuyt H, Bishehsari HE, Halloran This points to one possible reason why people in this group, on average, were less likely to get follow-up colonoscopy exams, Dr. Corley said. Yet theres clearly room for improvement. A. This demonstrates the longer-term protective value of completing the screening process, which is another new piece of information provided by the study, Dr. Corley said. 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). B, Can miss many polyps and some cancers. Any disagreement was resolved through discussion or by consulting a third author (A.T.). Faecal immunochemical test accuracy in patients referred for surveillance colonoscopy: a multi-centre cohort study. M, Parra-Blanco We assessed the quality of the evidence in our main analysis but also separately for patients with family history or personal history of CRC. Colonoscopy versus fecal immunochemical testing in colorectal-cancer screening. . Testing for fecal occult blood is commonly used as a cancer screen for colon cancer. Moher K, Grossman 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). Katsoula A, Paschos P, Haidich A, Tsapas A, Giouleme O. and P.P.) This test uses a specialized protein called an antibody. However, those who did not get a follow-up colonoscopy were about twice as likely to die of colorectal cancer over a 10-year period as those who did have a follow-up colonoscopy. In other words, the . Screening for Colorectal Cancer: US Preventive Services Task Force Recommendation Statement. Having a stool DNA test may lead to additional testing. Appropriateness of colonoscopy in Europe (EPAGE II). Diagnostic yield of the immunochemical fecal occult blood test in asymptomatic first degree relatives of colorectal cancer patients. 51% will have a precancerous polyp. If FIT testing is utilized as a CRC screening method, single-vial FIT screening is recommended by Polymedco, the National Cancer Institute, and the VHA. We estimated whether non-compliance with colonoscopy after a positive FIT is associated with increased CRC incidence and mortality. But because you use FIT every year, 10 . Fecal Immunochemical Test (FIT): common questions. LG, van Rijn RM, Whiting A negative Cologuard test means that the home test did not detect significant levels of DNA and/or hemoglobin biomarkers in the stool that are associated with colorectal cancer. et al; US Preventive Services Task Force. FIT only detects human blood from the lower intestines. GRADE handbook for grading quality of evidence and strength of recommendations. et al; American Cancer Society Colorectal Cancer Advisory Group; US Multi-Society Task Force; American College of Radiology Colon Cancer Committee. Castro Applying Grading of Recommendations Assessment, Development and Evaluation (GRADE) to diagnostic tests was challenging but doable. J, Rivera PM, Zwinderman GP; Expert Working Group on Fecal Immunochemical Tests for Hemoglobin, Colorectal Cancer Screening Committee, World Endoscopy Organization. Despite the use of an exhaustive and meticulous search strategy, we could only find 12 eligible studies. FIT costs about $20 or less and is covered by Medicare and most health insurance plans. LG, van Rijn This study will investigate the use of digital rectal exam (DRE) to obtain stool samples for the fecal immunochemical test (FIT) in patients due for screening colonoscopy and in pre-operative patients with known colorectal cancer. Eleven studies were cross-sectional and 1 was a randomized clinical trial.34 Two studies were reported only in abstract form.26,36 Nine studies included only first-degree relatives of CRC patients.26-28,30,32-34,36,37 Three studies included individuals either with a family history of CRC or prior history of CRC or advanced adenomas.29,31,35 Of these, only 2 studies reported results for subgroups.31,35, Eight studies evaluated quantitative FIT (OC-sensor/OC-micro, Eiken Chemical),26,27,29,31,33-36 while 4 studies used qualitative FITs (Hemosure, W.H.P.M. Published Online: June 19, 2017. doi:10.1001/jamainternmed.2017.2309. JL, Akl Two authors (A.K. // et al. Finally, we evaluated the clinical utility of FIT utilizing Fagan nomograms to depict posttest probability in patients at increased risk for CRC and AN. D, Liberati However, the robustness of our results was verified in a series of subgroup analyses. Findings M, LA, LM, Rooney Inc32,37; OC-light, Eiken Chemical28; and HemeSelect, Smith-Kline Diagnostics30). G, Mustafa World Health Organization International Agency for Research on Cancer. This meta-analysis assesses the diagnostic accuracy of fecal immunochemical tests for colorectal cancer or advanced neoplasia in asymptomatic patients with an a . 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. Accuracy of fecal immunochemical tests for colorectal cancer: systematic review and meta-analysis. Pinnacle Biolabs' Second Generation FIT offers results in minutes, and it is reportedly the top-selling colon cancer screening test in North America. Conclusions and Relevance F, Agustin Individuals at average risk are screened using the fecal immunochemical test (FIT), which has been available in British Columbia for the past 5 years Clinical Laboratory News New research underlines the importance of following up with a colonoscopy exam after a positive (abnormal) result on an at-home stool test to screen for colorectal cancer. et al. In the United States, cancer screening is a complex process that involves multiple steps and can be affected by many factors, Dr. Breslau said. After deduplication, we screened 2154 titles and abstracts and rejected 1952 records as noneligible. et al. A FIT kit is an alternative to a colonoscopy. Methodological quality of included studies graph: review authors' judgments about each item presented as percentages across all included studies, eFigure 4. independently extracted data and evaluated study quality using the Quality Assessment of Diagnostic Accuracy Studies2 tool, and evaluated the quality of the body of evidence by means of GRADE (Grading of Recommendations Assessment, Development, and Evaluation). We included 12 studies (6204 participants). 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. That . van Rossum As the broader DG30 criteria create a potentially enormous pool of low-risk patients, triage with FIT may lead to an overall increase in patients with false-positive . JY, Chan Gimeno-Garcia Reitsma These data indicate that participants who begin screening at the . Objective Cologuard found 93 percent of the cancers detected by screening colonoscopy. R, Carlos If you get a positive 'blood test' (there is no good blood test for colon cancer, BTW) you still need a colonoscopy; if you get a negative 'blood test' you still need a colonoscopy! Dwamena Colorectal Cancer: Estimated Incidence, Mortality and Prevalence Worldwide in 2012. Bariatric Surgery May Reduce Risk of Common Cancers, U.S. Department of Health and Human Services. R, Rozen The most common types of cancer that lead to positive fit test results include colorectal, breast, and lung cancers. Hierarchical summary receiver operating curve (HSROC) plot of sensitivity versus specificity of FIT for diagnosis of a) colorectal cancer; b) advanced neoplasia, eFigure 5. at the National Institutes of Health, An official website of the United States government, Colonoscopy after Positive FIT Test Cuts Risk of Colorectal Cancer Death, has been shown to reduce deaths from this disease, were twice as likely to die as those who did have a follow-up colonoscopy, peoples fears about the preparation for colonoscopy, cut the incidence of colorectal cancer deaths in half, Drug Targets Common Mutation in Pancreatic Cancer. To fully evaluate FIT sensitivity and effectiveness, a longitudinal study should assess its performance over several rounds of testing, taking into account the stage and site distribution of screen-detected CRCs and [interval CRCs] ICs in each round, they suggested. May 5, 2022 , by Elia Ben-Ari. BA, Sylvester Over that time, about 2 percent of the people, about 2,700 of them, had positive tests. This study emphasizes that cancer screening is really a process, not a single step, and shows the importance of completing all steps of the process, said gastroenterologist Douglas Corley, M.D., Ph.D., of Kaiser Permanente, Northern California, who was not involved in the study. This specific protein attaches to hemoglobin, the oxygen-carrying part of red blood cells. FA, Terhaar Sive Droste Fairly inexpensive. // Data have been presented for the as-screened population, because . Results were at least as good as from previous systematic reviews focusing n average-risk individuals.10,11,38 To ensure internal validity of our conclusions, we implemented current guidelines for the conduct and reporting of systematic reviews12,39 and used a prespecified protocol. Sensitivity 98%; . However, 14 percent of tests deliver false positive resultsfar higher than the FIT test. Offering colonoscopy to participants with a negative fit and a first degree relative with CRC increases the detection of advanced neoplasia in a screening program. For studies using multiple-sample FIT, positivity was rated based on the highest amount of fecal Hb measured in patient samples. The full text of the remaining 202 reports were assessed, and 12 studies met the inclusion criteria and were included in the systematic review.26-37 DARE indicates Database of Abstracts of Reviews of Effects. Our results suggest that given FIT safety, simplicity, low cost, and low discomfort, it could be used as an acceptable alternative for screening of individuals at increased risk for CRC. F, De Wijkerslooth Of the 432 participants who had a positive fecal immunochemical test, 285 underwent a colonoscopy (235 participants showed no polyps or cancer, 47 had polyps identified, and three had colorectal cancer identified). Heterogeneity and small sample size limit the precision of the results. NCCN Guidelines For Colorectal Cancer Screening (Version 2.2016). midas: meta-analysis of diagnostic accuracy studies. High specificity and sensitivity of FIT allow prompt referral of patients with positive results for further diagnostic investigation with colonoscopy, and exclusion of CRC with high certainty in individuals with negative results respectively. AM, Ladabaum Brozek We assessed the full text of the remaining 202 reports. The last search was performed in August 2016 (eFigure 1 in the Supplement). Systematic Review Data Repository. I asked what did it show, because they test for 11 different cancers or categories. It's also possible for the test to miss some cancers, which is called a false-negative result. However, recommendations for increased-risk individuals are more aggressive and support only use of colonoscopy. Bujanda MEDLINE, EMBASE, Cochrane Library, and gray literature sources through August 2016. A review article, Rockey DC: Occult gastrointestinal bleeding. Our search identified 3026 records (Figure 1). In our main analysis, FIT sensitivity and specificity for diagnosing CRC ranged from 0.25 to 1.00 (median, 0.81) and from 0.87 to 0.95 (median, 0.91), respectively. independently reviewed and screened titles and abstracts of articles retrieved and determined final eligibility through examination of full texts. Hierarchical summary receiver operating curve (HSROC) plot of sensitivity versus specificity for performance of FIT in studies with low risk of bias or concerns for applicability (QUADAS2), eFigure 6. What Causes Immunotherapys Heart-Related Side Effects? Heterogeneity and small sample size limit the precision of the results. No bowel prep. M, [This] raises the importance of being able to get the individual steps correct and completed as best you can because every step where you lose some people in follow-up can have a big impact., Study Adds to Debate about Screening for Melanoma, Ivosidenib with Chemotherapy New Option for Some People with AML, If you would like to reproduce some or all of this content, see Reuse of NCI Information for guidance about copyright and permissions. Most of these were at high or unclear risk of bias due to suboptimal study design.26,28,30,32,34,36,37 Only 3 studies had a mixed population with personal or familial history of CRC,29,31,35 and 2 studies presented results separately based on the patient history.31,35 A post hoc analysis of studies in individuals with family history of CRC using quantitative FIT resulted in similar summary estimates with the main analysis. 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. CG, Allison Although this looks like a clear advantage for fecal DNA (60 of 65 cancers detected compared . In asymptomatic people without risk factors who had a negative FIT within 2 years, colonoscopy had a very small chance of finding CRC. Such a strategy is associated with higher cost, lower adherence, and higher risk for rare, but serious, complications.2-6. 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. L, Gorber The fecal immunochemical test (FIT) is a screening test for colon cancer. In the case of permitted digital reproduction, please credit the National Cancer Institute as the source and link to the original NCI product using the original product's title; e.g., Colonoscopy after Positive FIT Test Cuts Risk of Colorectal Cancer Death was originally published by the National Cancer Institute., January 12, 2023, All studies assessed the accuracy of FIT for AN,26-37 but only 7 studies (4790 patients) reported data specifically for CRC.27,29,31-35 Prevalence of AN ranged between 3.2% and 14.5% and between 0.6% and 2.1% for CRC. Many successful colorectal cancer screening programs, including those in the United States, use some combination of stool-based tests, such as FIT, and screening colonoscopy, Dr. Corley said, so the new study results are very relevant to settings in the United States.. In this meta-analysis, FIT has high overall diagnostic accuracy for CRC and moderate accuracy for advanced neoplasia. Medicines and food do not interfere with the test. Quiz Ref IDUse of cutoff values between 15 to 25 g Hb/g feces had the best combination of sensitivity and specificity for the diagnosis of CRC (93% and 94%, respectively), as well as the highest LR+ (15.1) and lowest LR (0.07). Screening colonoscopy was better at finding cancer and pre-cancerous polyps than both Cologuard and the FIT test. These data support the annual use of FIT in individuals at increased risk for CRC as an alternative screening strategy for patients who refuse to use colonoscopy. // JK, Boland SP. N Engl J Med 1999;341:38-46 addresses some questions you might have if you turned out to have a positive test. 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. We excluded studies with symptomatic patients or patients with inflammatory bowel disease, hereditary nonpolyposis colorectal cancer, familial adenomatous polyposis, or studies for which 22 diagnostic tables could not be inferred. 20 participants of the 47 who had polyps had advanced adenomas . Mine were hemorrhoids. Stool samples collected at home are sent in for analysis. Ng This review was based on a prespecified protocol registered with PROSPERO 2016 (CRD42016037924) and is reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement.12. AS, Rutjes The average sensitivity of FIT for AN was 48% (95% CI, 39%-57%); and the average specificity was 93% (95% CI, 91%-94%), yielding an LR+ of 6.55 (95% CI, 5.0-8.5) and an LR of 0.57 (95% CI, 0.48-0.67) (GRADE: very low). CM, Gatsonis . A positive FIT can also be due to a polyp, a pre . Respective values for AN were sensitivity, 46% (95% CI, 37%-56%); specificity, 93% (95% CI, 90%-95%); LR+, 6.60 (95% CI, 4.90-8.70); and LR, 0.58 (95% CI, 0.48-0.69). JAMA Intern Med. The DNA test is 92% effective at detecting cancers. 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. Levin Hierarchical models were used to synthesize available evidence. The use of FIT in symptomatic patients is associated with a better prognosis in CRC. P, et al; COLONPREV Study Investigators. The researchers compared the numbers of new colorectal cancer cases diagnosed, deaths from colorectal cancer, and deaths from any cause in the two groups over time for up to 10 years after an initial positive FIT result. Assuming a pretest probability of 0.8% for CRC and 10.2% for AN (median prevalence in 7 and 12 studies included in the present meta-analysis, respectively), a positive result increases the probability of CRC to 8.0% and probability of AN to 42.0%. It is a noninvasive, private way to check for colon cancer without having to leave your house. Statistical analysis was performed with Stata software version 13.0 (Stata Corporation), using metandi and midas modules. We assessed the stability of our findings in a series of sensitivity analyses (eTable 1 in the Supplement). Quality assessment summary: review authors judgments about each risk of bias item for each included study, eFigure 3. Further research with rigorous diagnostic accuracy studies and randomized clinical trials is warranted to assess the full effectiveness of FIT implementation as a means to promote more individualized and more flexible alternative screening options in patients at higher risk of CRC based on their own values and preferences. They followed these individuals under four endpoints: initial colonoscopy, health plan disenrollment, death, or December 31, 2015, comparing them against a non-CRC control group. Study Selection Grading quality of evidence and strength of recommendations in clinical practice guidelines: part 3 of 3. the GRADE approach to developing recommendations. Use of cutoff values between 15 to 25 g Hb/g feces had the best combination of sensitivity and specificity for the diagnosis of CRC (93% and 94%, respectively), as well as the highest LR+ (15.1) and lowest LR (0.07). by Carmen Phillips, December 2, 2022, KG. et al. Screening for familial colorectal cancer with a sensitive immunochemical fecal occult blood test: a pilot study. In 3 relevant studies, sensitivity for CRC varied from 67% to 100% and specificity from 83% to 95%.