RESUMO
BACKGROUND & AIMS: Endoscopic Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) detection is invasive and expensive. Nonendoscopic BE/EAC detection tools are guideline-endorsed alternatives. We previously described a 5-methylated DNA marker (MDM) panel assayed on encapsulated sponge cell collection device (CCD) specimens. We aimed to train a new algorithm using a 3-MDM panel and test its performance in an independent cohort. METHODS: Algorithm training and test samples were from 2 prospective multicenter cohorts. All BE cases had esophageal intestinal metaplasia (with or without dysplasia/EAC); control subjects had no endoscopic evidence of BE. The CCD procedure was followed by endoscopy. From CCD cell lysates, DNA was extracted, bisulfite treated, and MDMs were blindly assayed. The algorithm was set and locked using cross-validated logistic regression (training set) and its performance was assessed in an independent test set. RESULTS: Training (N = 352) and test (N = 125) set clinical characteristics were comparable. The final panel included 3 MDMs (NDRG4, VAV3, ZNF682). Overall sensitivity was 82% (95% CI, 68%-94%) at 90% (79%-98%) specificity and 88% (78%-94%) sensitivity at 84% (70%-93%) specificity in training and test sets, respectively. Sensitivity was 90% and 68% for all long- and short-segment BE, respectively. Sensitivity for BE with high-grade dysplasia and EAC was 100% in training and test sets. Overall sensitivity for nondysplastic BE was 82%. Areas under the receiver operating characteristic curves for BE detection were 0.92 and 0.94 in the training and test sets, respectively. CONCLUSIONS: A locked 3-MDM panel algorithm for BE/EAC detection using a nonendoscopic CCD demonstrated excellent sensitivity for high-risk BE cases in independent validation samples. (Clinical trials.gov: NCT02560623, NCT03060642.).
RESUMO
The multi-target stool DNA (mt-sDNA) test screens for colorectal cancer by analyzing DNA methylation/mutation and hemoglobin markers to algorithmically derive a qualitative result. A new panel of highly discriminant candidate methylated DNA markers (MDM) was recently developed. Performance of the novel MDM panel, with hemoglobin, was evaluated in a simulated screening population using archived stool samples weighted to early-stage colorectal cancer and prospectively collected advanced precancerous lesions (APL). Marker selection study (MSS) and separate preliminary independent verification studies (VS) were conducted utilizing samples from multi-center, case-control studies. Sample processing included targeted MDM capture, bisulfite conversion, and MDM quantitation. Fecal hemoglobin was quantified using ELISA. Samples were stratified into 75%/25% training-testing sets; model outcomes were cross-validated 1,000 times. All laboratory operators were blinded. The MSS included 232 cases (120 colorectal cancer/112 APLs) and 490 controls. The VS featured 210 cases (112 colorectal cancer/98 APLs) and 567 controls; APLs were 86.7% adenomas and 13.3% sessile serrated lesions (SSL). Average age was 65.5 (cases) and 63.2 (controls) years. Mean sensitivity in the VS from cross-validation was 95.2% for colorectal cancer and 57.2% for APLs, with specificities of 89.8% (no CRC/APLs) and 92.4% (no neoplasia). Subgroup analyses showed colorectal cancer sensitivities of 93.4% (stage I) and 94.2% (stage II). APL sensitivity was 82.9% for high-grade dysplasia, 73.4% for villous lesions, 49.8% for tubular lesions, and 30.2% for SSLs. These data support high sensitivity and specificity for a next-generation mt-sDNA test panel. Further evaluation of assay performance will be characterized in a prospective, multi-center clinical validation study (NCT04144738). PREVENTION RELEVANCE: This study highlights performance of the next-generation mt-sDNA test, which exhibits high sensitivity and specificity for detecting colorectal cancer and APLs. This noninvasive option has potential to increase screening participation and clinical outcomes. A multi-center, clinical validation trial is underway. See related commentary by Bresalier, p. 93.