Discovery and validation of methylation signatures in circulating cell-free DNA for early detection of esophageal cancer: A case-control study.

Abstract

e16027 Background: The pivotal goal of esophageal cancer (ESCA) screening is to identify early-stage cancer or precancerous lesions when curable treatments are available. Methylation of circulating-free DNA (cfDNA) has shown promising results in the early detection of multiple tumors recently. Here we conducted a prospective study to investigate the performance of cfDNA methylation in the early detection of ESCA. Methods: Specific methylation markers for ESCA were identified and optimized based on 24 esophageal tumor and its corresponding adjacent tissues. Age-matched participants with ESCA (n = 136), benign esophageal disease (n = 21) and healthy controls (n = 126) were randomized into the training and testing sets to develop an early-detection classifier. Results: In total, 921 differentiated methylation blocks (DMBs) between tumor and adjacent tissues were identified, of which 679 (73.7%) showed higher methylation level and 242 (26.3%) had lower methylation level in tumor tissues. In the training set, the specificity of the model built with these DMBs was 94.1% (95% CI, 85.5%−98.4%) and the sensitivity was 86.0% (95% CI, 72.2%−94.8%). The sensitives increased with stages, which were 77.8% (95% CI, 39.8%−97.2%), 90.9% (95% CI, 58.7%−99.8%), 83.3% (95% CI, 51.7%−97.9%) and 100.0% (95%CI, 63.1%−100.0%) for stage I-IV, respectively. Similar results were observed in the testing set with area under curve (AUC) of 0.932 (95% CI, 0.887−0.977). Conclusions: The cfDNA methylation profiles distinguished ESCAs from healthy individuals and benign esophageal diseases with promising sensitivity and specificity. Consideration of the potential value of early detection in ESCAs, further evaluation in larger prospective studies is warranted.