Plasma Septin9 versus fecal immunochemical testing for colorectal cancer screening: a prospective multicenter study.

BACKGROUND: Screening improves outcomes related to colorectal cancer (CRC); however, suboptimal participation for available screening tests limits the full benefits of screening. Non-invasive screening using a blood based assay may potentially help reach the unscreened population. OBJECTIVE: To compare the performance of a new Septin9 DNA methylation based blood test with a fecal immunochemical test (FIT) for CRC screening. DESIGN: In this trial, fecal and blood samples were obtained from enrolled patients. To compare test sensitivity for CRC, patients with screening identified colorectal cancer (n = 102) were enrolled and provided samples prior to surgery. To compare test specificity patients were enrolled prospectively (n = 199) and provided samples prior to bowel preparation for screening colonoscopy. MEASUREMENTS: Plasma and fecal samples were analyzed using the Epi proColon and OC Fit-Check tests respectively. RESULTS: For all samples, sensitivity for CRC detection was 73.3% (95% CI 63.9-80.9%) and 68.0% (95% CI 58.2-76.5%) for Septin9 and FIT, respectively. Specificity of the Epi proColon test was 81.5% (95% CI 75.5-86.3%) compared with 97.4% (95% CI 94.1-98.9%) for FIT. For paired samples, the sensitivity of the Epi proColon test (72.2% -95% CI 62.5-80.1%) was shown to be statistically non-inferior to FIT (68.0%-95% CI 58.2-76.5%). When test results for Epi proColon and FIT were combined, CRC detection was 88.7% at a specificity of 78.8%. CONCLUSIONS: At a sensitivity of 72%, the Epi proColon test is non- inferior to FIT for CRC detection, although at a lower specificity. With negative predictive values of 99.8%, both methods are identical in confirming the absence of CRC. TRIAL REGISTRATION: ClinicalTrials.gov NCT01580540.

Validation of a real-time PCR-based qualitative assay for the detection of methylated SEPT9 DNA in human plasma.

BACKGROUND: Epi proColon® is a new blood-based colorectal cancer (CRC) screening test designed to determine the methylation status of a promoter region of the SEPT9 (septin 9) gene in cell-free DNA isolated from plasma. We describe the analytical and clinical performance of the test. METHODS: Analytical performance at 4 testing laboratories included determination of limit of detection, precision, and reproducibility of the SEPT9 test. Clinical performance was evaluated in a prospective study by use of samples (n = 1544) from subjects enrolled in the PRESEPT clinical trial. Results were analyzed by comparison with colonoscopy, the reference standard. RESULTS: The limit of detection for methylated SEPT9 DNA was 7.8 pg/mL (95% CI 6-11 pg/mL) corresponding to <2 genome copies of methylated SEPT9 per milliliter of plasma. In the prospective clinical trial, sensitivity for all stages of CRC was 68% (95% CI 53%-80%) and for stage I-III CRC, 64% (48%-77%). Adjusted specificity, on the basis of negative colonoscopy findings, was 80.0% (78%-82%). SIGNIFICANCE: The Epi proColon test is a simple, real-time PCR-based assay for the detection of methylated SEPT9 DNA in blood that may provide a noninvasive CRC screening alternative for people noncompliant with current CRC screening guidelines.

Rate of detection of high-risk HPV with two assays in women ≥ 30 years of age.

BACKGROUND: High-risk (HR) human papillomavirus (HPV) prevalence rates, as determined by the Cervista(®) HPV HR test, in women aged ≥30 years in a routine screening population have not been studied. OBJECTIVES: The primary objective of this study was to estimate HR HPV prevalence in women negative for intraepithelial lesion or malignancy (NILM) cytology using the CERVISTA HPV HR test. The study also compared HR HPV prevalence rates in women aged ≥30 years and NILM cytology using the CERVISTA HPV HR and Hybrid Capture(®) 2 (hc2) tests. STUDY DESIGN: A multi-center study was conducted to analyze HR HPV prevalence rates using the CERVISTA HPV HR test from residual ThinPrep(®) specimens. HR HPV positive rates were determined for hc2; percent agreement between the CERVISTA HPV HR and the hc2 tests were reported. RESULTS: HR HPV prevalence rates among women with NILM cytology were not statistically different between the CERVISTA HPV HR and hc2 tests (6.92% [98/1417] versus 5.93% [84/1417], respectively; P>0.05). The overall percent agreement between the tests was 95.3% (1351/1417; 95% confidence interval [CI]: 94.1-96.3; κ=0.61, 95% CI: 0.53-0.70). There were no statistically significant differences between tests across age groups or investigational sites. For both tests, there was a statistically significant decrease in HR HPV positive results as age increases (CERVISTA HPV HR, P=0.0009; hc2, P<0.0001). DISCUSSION: There is no statistically significant difference between HR HPV prevalence rates obtained with the CERVISTA HPV HR and hc2 tests in women aged ≥30 years with NILM cytology.