Minimally Invasive Molecular Approaches for the Detection of Barrett’s Esophagus and Esophageal Adenocarcinoma

项目概要/摘要 食管腺癌（EAC）是一种预后不良的致命癌症（5年生存率<20%）， 在症状出现后诊断，但早期诊断的生存率很高。肠上皮化生， 或Barrett食管（BE），是EAC的唯一已知的前体，并通过发展 发育不良EAC可以通过内镜治疗异型增生来预防。因此，内镜筛查BE和 建议内镜监测以检测发育异常和EAC。然而，> 60%的流行BE 仍然未被诊断，90%的EAC病例是在BE监测计划之外诊断的。主要 BE筛查的障碍是内窥镜检查的侵入性和高成本。此外，建议进行筛查 仅在慢性胃食管反流（GERD）患者中，尽管50%的BE/EAC患者未报告 GERD症状。内镜监测错过了33%的流行EAC和发育不良，由于斑块 异型增生/EAC的分布和活检取样不足。因此，内窥镜的总体有效性 监视也受到严重损害。 我们使用还原型亚硫酸氢盐测序（RRBS）来鉴定一组甲基化DNA标记 （MDM）BE和发育不良/EAC，然后进行验证。MDM组具有高度判别性（AUC> 0.9） 用于BE和普遍发育不良/EAC。当对通过海绵获得的食管细胞学标本进行检测时 在两项病例对照研究中，使用线上（SOS）器械检测BE的准确性较高（AUC 0.97-1.0 在转诊人群中。FDA批准的SOS装置（Capnostics，多尔斯敦，PA）是一种25 mm聚氨酯 海绵压缩在一个可溶解的胶囊壳，膨胀成一个球，在胃后， 吞下去当通过一根附加的绳子从嘴里拉出时， 实现了粘膜。护士管理的SOS测试是安全的，耐受性良好，参与率高 (65%).因此，我们的中心假设是，食管细胞学检测的新型判别MDM 通过SOS装置获得的标本将能够在筛查中准确检测BE和发育异常/EAC， 有和没有慢性GERD的人群。我们将通过三个具体目标来检验这一假设。 在具体目标1中，我们将在筛查中测量SOS BE试验的阳性和阴性预测值 符合条件的人群从初级保健诊所在马约卫生系统，并比较这些价值观， 有和没有GERD。在具体目标2中，我们将确定临床和人口统计学因素，特别是GERD， 影响预定SOS BE测试预测算法的准确性。在具体目标3中，我们将测量 使用SOS器械，MDM检测BE中异型增生/EAC的准确性。 利用创新的微创（非内窥镜）和分子方法，该提案将 有利地影响BE检测和监测，从而实现有效治疗并改善EAC结果。

PROJECT SUMMARY/ABSTRACT Esophageal adenocarcinoma (EAC) is a lethal cancer with poor outcomes (5 year survival <20%), when diagnosed after the onset of symptoms, but survival is excellent when diagnosed early. Intestinal metaplasia, or Barrett’s esophagus (BE), is the only known precursor of EAC, and progresses to EAC via development of dysplasia. EAC can be prevented by endoscopic therapy of dysplasia. Hence endoscopic screening for BE and endoscopic surveillance to detect dysplasia and EAC are recommended. However, > 60% of prevalent BE remains undiagnosed and 90% of all EAC cases are diagnosed outside a BE surveillance program. The major barrier to BE screening is the invasiveness and high cost of endoscopy. Further, screening is recommended only in those with chronic gastroesophageal reflux (GERD), despite 50% of BE/EAC patients not reporting GERD symptoms. Endoscopic surveillance misses 33% of prevalent EAC & dysplasia, due to the patchy distribution of dysplasia/EAC, and inadequate biopsy sampling. Hence the overall effectiveness of endoscopic surveillance is also severely compromised. We used reduced representation bisulfite sequencing (RRBS) to identify a panel of methylated DNA markers (MDMs) of BE and dysplasia/EAC followed by validation. MDM panels were highly discriminant (AUCs > 0.9) for BE and prevalent dysplasia/EAC. When assayed on esophageal cytology specimens obtained via a sponge on string (SOS) device, BE was detected with high accuracy (AUCs 0.97-1.0) in two case control studies done in referral populations. The FDA approved SOS device (Capnostics, Doylestown, PA) is a 25 mm polyurethane sponge compressed in a dissolvable capsule shell, which expands into a sphere in the stomach after being swallowed. When pulled out through the mouth via an attached string, sampling of the entire esophageal mucosa is achieved. The nurse-administered SOS test is safe and well tolerated with high participation rates (65%). Hence our central hypothesis is that novel discriminant MDMs assayed on esophageal cytology specimens obtained via the SOS device will enable accurate BE and dysplasia/EAC detection, in a screening population with and without chronic GERD. We will test this hypothesis by three specific aims. In specific Aim 1, we will measure the positive and negative predictive value of the SOS BE test in a screening eligible population from primary care clinics in the Mayo Health System and compare these values in those with and without GERD. In specific Aim 2 we will identify clinical and demographic factors, particularly GERD, influencing the accuracy a predetermined SOS BE test prediction algorithm. In Specific Aim 3, we will measure the accuracy of MDMs for the detection of dysplasia/EAC in BE, using the SOS device. Utilizing an innovative, minimally invasive (non-endoscopic) and molecular approach, this proposal will favorably impact BE detection and surveillance, enabling effective treatment, and improved EAC outcomes.