Efficient detection and post-surgical monitoring of colon cancer with a multi-marker DNA methylation liquid biopsy
Menée à partir de 179 échantillons plasmatiques prélevés sur des témoins sains et des patients atteints d'un cancer colorectal ou d'un adénome puis validée à partir de 182 échantillons plasmatiques supplémentaires, cette étude met en évidence la performance d'un test quantitatif par PCR utilisant un panel de 10 marqueurs de méthylation de l'ADN tumoral circulant pour détecter un cancer colorectal et surveiller l'évolution de la maladie après une intervention chirurgicale
Colorectal cancer recurrence is one of the main causes of death. Early prediction of recurrence by minimal residual disease detection and longitudinal tumor monitoring can improve patient outcomes. Next-generation sequencing methods analyzing circulating tumor DNA (ctDNA) in blood can predict recurrence with high accuracy, but these methods are too expensive and complex to be broadly deployable. We have developed a cost-effective and easily implementable single-tube qPCR method (mqMSP) for quantifying a panel of ctDNA methylation markers. Using this panel to monitor patients after surgery can predict cancer recurrence with high accuracy and well in advance of methods in current use.Multiplex assays, involving the simultaneous use of multiple circulating tumor DNA (ctDNA) markers, can improve the performance of liquid biopsies so that they are highly predictive of cancer recurrence. We have developed a single-tube methylation-specific quantitative PCR assay (mqMSP) that uses 10 different methylation markers and is capable of quantitative analysis of plasma samples with as little as 0.05% tumor DNA. In a cohort of 179 plasma samples from colorectal cancer (CRC) patients, adenoma patients, and healthy controls, the sensitivity and specificity of the mqMSP assay were 84.9% and 83.3%, respectively. In a head-to-head comparative study, the mqMSP assay also performed better for detecting early-stage (stage I and II) and premalignant polyps than a published SEPT9 assay. In an independent longitudinal cohort of 182 plasma samples (preoperative, postoperative, and follow-up) from 82 CRC patients, the mqMSP assay detected ctDNA in 73 (89.0%) of the preoperative plasma samples. Postoperative detection of ctDNA (within 2 wk of surgery) identified 11 of the 20 recurrence patients and was associated with poorer recurrence-free survival (hazard ratio, 4.20; P = 0.0005). With subsequent longitudinal monitoring, 14 patients (70%) had detectable ctDNA before recurrence, with a median lead time of 8.0 mo earlier than seen with radiologic imaging. The mqMSP assay is cost-effective and easily implementable for routine clinical monitoring of CRC recurrence, which can lead to better patient management after surgery.Sequencing data have been submitted to the National Center for Biotechnology Information’s BioProject (accession no. PRJNA687345).
Proceedings of the National Academy of Sciences , article en libre accès, 2020