Dataset Information

Performance of a quantitative fecal immunochemical test for detecting advanced colorectal neoplasia: a prospective cohort study.

ABSTRACT: The fecal immunochemical test (FIT) is easier to use and more sensitive than the guaiac fecal occult blood test, but it is unclear how to optimize FIT performance. We compared the sensitivity and specificity for detecting advanced colorectal neoplasia between single-sample (1-FIT) and two-sample (2-FIT) FIT protocols at a range of hemoglobin concentration cutoffs for a positive test.We recruited 2,761 average-risk men and women ages 49-75 referred for colonoscopy within a large nonprofit, group-model health maintenance organization (HMO), and asked them to complete two separate single-sample FITs. We generated receiver-operating characteristic (ROC) curves to compare sensitivity and specificity estimates for 1-FIT and 2-FIT protocols among those who completed both FIT kits and colonoscopy. We similarly compared sensitivity and specificity between hemoglobin concentration cutoffs for a single-sample FIT.Differences in sensitivity and specificity between the 1-FIT and 2-FIT protocols were not statistically significant at any of the pre-specified hemoglobin concentration cutoffs (10, 15, 20, 25, and 30 ?g/g). There was a significant difference in test performance of the one-sample FIT between 50 ng/ml (10 ?g/g) and each of the higher pre-specified cutoffs. Disease prevalence was low.A two-sample FIT is not superior to a one-sample FIT in detection of advanced adenomas; the one-sample FIT at a hemoglobin concentration cutoff of 50 ng/ml (10 ?g/g) is significantly more sensitive for advanced adenomas than at higher cutoffs. These findings apply to a population of younger, average-risk patients in a U.S. integrated care system with high rates of prior screening.

SUBMITTER: Liles EG

PROVIDER: S-EPMC5932873 | biostudies-other | 2018 May

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Performance of a quantitative fecal immunochemical test for detecting advanced colorectal neoplasia: a prospective cohort study.

Liles Elizabeth G EG Perrin Nancy N Rosales Ana G AG Smith David H DH Feldstein Adrianne C AC Mosen David M DM Levin Theodore R TR

BMC cancer 20180502 1

<h4>Background</h4>The fecal immunochemical test (FIT) is easier to use and more sensitive than the guaiac fecal occult blood test, but it is unclear how to optimize FIT performance. We compared the sensitivity and specificity for detecting advanced colorectal neoplasia between single-sample (1-FIT) and two-sample (2-FIT) FIT protocols at a range of hemoglobin concentration cutoffs for a positive test.<h4>Methods</h4>We recruited 2,761 average-risk men and women ages 49-75 referred for colonosco ...[more]

PMID: 29720130

Similar Datasets

Project description:BackgroundFecal immunochemical tests (FITs) are the most widely used non-invasive tests in colorectal cancer (CRC) screening. However, evidence about the direct comparison of the test performance of the self-administered qualitative a laboratory-based quantitative FITs in a CRC screening setting is sparse.MethodsBased on a CRC screening trial (TARGET-C), we included 3144 pre-colonoscopy fecal samples, including 24 CRCs, 230 advanced adenomas, 622 non-advanced adenomas, and 2268 participants without significant findings at colonoscopy. Three self-administered qualitative FITs (Pupu tube) with positivity thresholds of 8.0, 14.4, or 20.8 μg hemoglobin (Hb)/g preset by the manufacturer and one laboratory-based quantitative FIT (OC-Sensor) with a positivity threshold of 20 μg Hb/g recommended by the manufacturer were tested by trained staff in the central laboratory. The diagnostic performance of the FITs for detecting colorectal neoplasms was compared in the different scenarios using the preset and adjusted thresholds (for the quantitative FIT).ResultsAt the thresholds preset by the manufacturers, apart from the qualitative FIT-3, significantly higher sensitivities for detecting advanced adenoma were observed for the qualitative FIT-1 (33.9% [95% CI: 28.7-39.4%]) and qualitative FIT-2 (22.2% [95% CI: 17.7-27.2%]) compared to the quantitative FIT (11.7% [95% CI: 8.4-15.8%]), while at a cost of significantly lower specificities. However, such difference was not observed for detecting CRC. For scenarios of adjusting the positivity thresholds of the quantitative FIT to yield comparable specificity or comparable positivity rate to the three qualitative FITs accordingly, there were no significant differences in terms of sensitivity, specificity, positive/negative predictive values and positive/negative likelihood ratios for detecting CRC or advanced adenoma between the two types of FITs, which was further evidenced in ROC analysis.ConclusionsAlthough the self-administered qualitative and the laboratory-based quantitative FITs had varied test performance at the positivity thresholds preset by the manufacturer, such heterogeneity could be overcome by adjusting thresholds to yield comparable specificities or positivity rates. Future CRC screening programs should select appropriate types of FITs and define the thresholds based on the targeted specificities and manageable positivity rates.

Project description:To compare the performance of a new blood test for colorectal cancer (CRC) to an established fecal immunochemical test (FIT) in a study population with the full range of neoplastic and non-neoplastic pathologies encountered in the colon and rectum.Volunteers were asked to complete a FIT prior to colonoscopy. Blood was collected after bowel preparation but prior to colonoscopy, and plasma was assayed for the presence of methylated BCAT1 and IKZF1 DNA using a multiplex real-time PCR assay. Sensitivity and specificity estimates for the blood test were calculated from true- and false-positive rates for neoplasia and compared with FIT at a range of fecal hemoglobin (Hb) concentration positivity thresholds.In total, 1,381 volunteers (median age 64 years; 49% male) completed both tests prior to colonoscopy. Estimated sensitivity of the BCAT1/IKZF1 blood test for CRC was 62% (41/66; 95% confidence interval 49-74%) with a specificity of 92% (1207/1315; 90-93%). FIT returned the same specificity at a cutoff of 60??g Hb/g, at which its corresponding sensitivity for cancer was 64% (42/66; 51-75%). In the range of commonly used FIT cutoffs, respective cancer sensitivity and specificity estimates with FIT were: 59% (46-71%) and 93% (92-95%) at 80??g Hb/g, and 79% (67-88%) and 81% (78-83%) at 10??g Hb/g. Although estimated sensitivities were not significantly different between the two tests for any stage of cancer, FIT showed a significantly higher sensitivity for advanced adenoma at the lower cutoffs. Specificity of FIT, but not of the BCAT1/IKZF1 blood test, deteriorated substantially in people with overt blood in the feces. When combining FIT (cutoff 10??g Hb/g) with the BCAT1/IKZF1 blood test, sensitivity for cancer was 89% (79-96%) at 74% (72-77%) specificity.A test based on detection of methylated BCAT1/IKZF1 DNA in blood has comparable sensitivity but better specificity for CRC than FIT at the commonly used positivity threshold of 10??g Hb/g. Further evaluation of the new test relative to FIT in the population screening context is now required to fully understand the potential advantages and disadvantages of these biomarkers in screening.

Dataset Information

Performance of a quantitative fecal immunochemical test for detecting advanced colorectal neoplasia: a prospective cohort study.

Publications

Performance of a quantitative fecal immunochemical test for detecting advanced colorectal neoplasia: a prospective cohort study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets