PO.CL01.07 · 临床研究
一种用于生物标志物发现和肿瘤负荷评估的高灵敏度、无组织血液检测的验证
Validation of a sensitive, tissue-free blood test for biomarker discovery and tumor burden assessment
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：循环肿瘤DNA（ctDNA）分析在分子和计算技术上的快速进展正在变革精准肿瘤学，使得无需侵入性组织取样即可进行肿瘤检测、复发监测和治疗选择。在这些方法中，ctDNA的甲基化分析提供了一种灵敏且定量的肿瘤负荷测量手段。然而，信噪比在不同癌症类型和技术之间存在差异，凸显了对肿瘤特异性检测优化和严格验证的需求。我们此前开发了一种无组织、基于甲基化的检测，并证明了其在肺癌、结直肠癌和肝癌中的临床有效性。在此，我们报告在更多肿瘤类型中扩展的、更大规模的验证，包括胰腺癌（PDAC）和胆道癌（BTC）。
方法：CanCatch® Surf分类器经过训练并随后锁定，如前所述。总分析性能测试数据集包含>1,000份人工构建和临床样本（10-30 ng投入量）。在本研究中，我们构建了PDAC和BTC来源细胞系与cfDNA混合物的稀释系列，跨越0.001-0.5%的肿瘤等位基因分数（TAF）。通过将PDAC和BTC患者的测序读长与无癌供者的读长按既定比例（0.001-0.5%）数字化混合，生成了计算机模拟滴定数据集。Probit回归将检测限（LoD）确定为以≥95%概率检出的最低TAF；空白限（LoB）为年龄匹配的无癌供者中每样本的阳性率。
结果：PDAC和BTC的分析灵敏度在计算机模拟混合物、细胞系稀释和cfDNA滴定中均达到0.02%，在72名年龄匹配的无癌供者中无假阳性（0%；95% CI 0-5.0%）。对176份治疗前血浆（57份PDAC，50份BTC，69份对照）的评估显示，PDAC的灵敏度为84.2%（I期75.0%，II期86.7%，III期83.3%，IV期100%），BTC的灵敏度为82.0%（I期71.4%，II期66.7%，III期93.3%，IV期92.3%），两者的特异性均为98.6%；更大规模的队列正在进行中，更新结果将在可获得时呈现。
结论：CanCatch® Surf在实体瘤中检测ctDNA的无创方法已展现出与传统组织检测方法相当的性能，因而有望在监测疾病复发和评估治疗效果方面获得更广泛的临床应用。
查看英文原文 English abstract
Background: Rapid progress in molecular and computational technologies for circulating tumor DNA (ctDNA) analysis is transforming precision oncology, allowing tumor detection, relapse surveillance, and treatment selection without invasive tissue sampling. Among these approaches, methylation profiling of ctDNA offers a sensitive and quantitative measure of tumor burden. However, signal-to-noise ratios varies across cancer types and technologies, underscoring the need for tumor-specific assay optimization and rigorous validation. We previously developed a tissue-free, methylation-based assay and demonstrated its clinical validity in lung, colorectal, and liver cancers. Here we report expanded, larger scale validation across additional tumor types, including pancreatic cancer (PDAC) and bile tract cancer (BTC).
Methods: The CanCatch ® Surf classifier was trained and subsequently locked, as previously described. The total analytical performance testing dataset comprises >1,000 contrived and clinical samples (10-30 ng input). In this study, we constructed dilution series of PDAC- and BTC-derived cell-line and cfDNA mixtures spanning 0.001-0.5% tumor allele fraction (TAF). The in-silico titration dataset was generated by digitally blending sequencing reads from PDAC and BTC patients with those from cancer-free donors at defined proportions (0.001-0.5%). Probit regression identified the limit of detection (LoD) as the lowest TAF detected with ≥95% probability; the limit of blank (LoB) was the per-sample positivity rate in age-matched cancer-free donors.
Results: The analytical sensitivity for PDAC and BTC reached 0.02% for in silico mixtures, cell-line dilutions and cfDNA titrations, with no false positives among 72 age-matched cancer-free donors (0 %; 95% CI 0-5.0%). Evaluation of 176 pre-treatment plasmas (57 PDAC, 50 BTC, 69 controls) demonstrated a sensitivity of 84.2% for PDAC (stage I 75.0 %, II 86.7%, III 83.3%, IV 100%) and 82.0% for BTC (stage I 71.4%, II 66.7%, III 93.3%, IV 92.3%), both at 98.6 % specificity; larger cohorts are in progress, and updated results will be presented as available.
Conclusions: CanCatch ® Surf's non-invasive approach to ctDNA detection in solid tumors has demonstrated performance comparable to traditional tissue-based methods, thus holding promise for broader clinical use in monitoring disease recurrence and assessing treatment effectiveness.
利益披露 Disclosure
Z. Deng, None..
X. Li, None..
X. Kang, None..
J. Xu, None..
J. Su, None..
X. Chen, None..
Q. You, None..
X. Yang, None..
Z. Zhang, None..
B. Li, None.