Abstract A077: Integrated biomarker analysis of circulating tumor cells, circulating tumor DNA and extracellular vesicles in a single blood draw: Longitudinal monitoring for pancreatic cancer
Yu-Shu Cheng, Yin Zou, Ashleigh Montle, Shamileh Fouladdel, Anders Bogard, Nicole Peterson, Vaibhav Sahai, Sunitha NagrathAbstract
Introduction:
The high fatality of pancreatic cancer is primarily attributed to late-stage diagnosis and high recurrence rates. Among patients eligible for resection surgery, recurrence rates reach approximately 70% with a median survival of 27.9 months, highlighting the urgent need to longitudinally monitor these patients and identify those requiring more intensive intervention to prevent relapse. Liquid biopsy is a promising approach that detects blood biomarkers with high sensitivity to tumor dynamics than conventional imaging, while enabling longitudinal monitoring through minimally invasive, repetitive sampling. This study aims to develop an integrated workflow for the simultaneous analysis of blood-based circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and tumor-derived extracellular vesicles (tEVs). The end goal is to construct a multimodal prognostic model that integrates these complementary biomarker inputs to overcome the limitations of single-analyte approaches and achieve more robust risk stratification.
Methods:
A high-throughput microfluidic platform was developed for label-free blood plasma separation without external force fields such as magnetic separation or centrifugation. The device was characterized across flow rates of 650–1450 µL/min using whole blood at varying dilution factors, with plasma yield and purity evaluated at each condition. The separated plasma fraction is used for downstream isolation of tEVs and ctDNA, while the cellular fraction is used for CTC enrichment. CTCs are identified and enumerated via immunofluorescence staining. ctDNA is detected by dPCR, with size profile and concentration further characterized. EVs are assessed by Western blot for pancreatic cancer-associated marker expression, and nanoparticle tracking analysis is used to quantify concentration and size distribution.
Results:
Our plasma separation microfluidic platform achieves ∼99% separation efficiency and 6.5% plasma yield using 4-fold diluted blood at 1,450 µL/min — a throughput three-fold higher than the highest previously reported in the literature. From the same blood draw, CTC enumeration is performed; ctDNA fragmentation profile, concentration, and KRAS mutation status are analyzed; and tEV size distribution, concentration, and proteomic markers are characterized. These multimodal features will be integrated as inputs for a longitudinal machine learning model for pancreatic cancer risk stratification.
Conclusion:
Our platform demonstrates the feasibility of an integrated multi-analyte liquid biopsy workflow from a single blood draw. The long-term goal is to leverage tumor-specific information at the genomic, transcriptomic, and proteomic levels to construct a robust machine learning model for longitudinal tumor monitoring, ultimately enabling more informed clinical decision-making for pancreatic cancer patients.
Citation Format:
Yu-Shu Cheng, Yin Zou, Ashleigh Montle, Shamileh Fouladdel, Anders Bogard, Nicole Peterson, Vaibhav Sahai, Sunitha Nagrath. Integrated biomarker analysis of circulating tumor cells, circulating tumor DNA and extracellular vesicles in a single blood draw: Longitudinal monitoring for pancreatic cancer [abstract]. In: Proceedings of the AACR Conference on Pancreatic Cancer: New Frontiers in Biology and Therapeutic Development; 2026 Sep 25-28; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(18_Suppl_2):Abstract nr A077.