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Updated: Jan 25, 2026

A Standardized Liquid Biopsy Preanalytical Protocol for Downstream Circulating-Free DNA Applications
Published on: September 16, 2022
Liquid Biopsy: Is There an Advantage to Analyzing Circulating Exosomal DNA Compared to cfDNA or Are They the Same?
1Department for Visceral, Thoracic and Vascular Surgery at the University Hospital, Technical University Dresden, Dresden, Germany. christoph.kahlert@uniklinikum-dresden.de.
Abstract:
Cancer is one of the leading causes of death worldwide. This life-threatening disease requires novel strategies for the early detection and therapy response prediction. Circulating DNA was first described 70 years ago. However, only the recent evolution in the PCR-based sequencing techniques allow the minimally invasive molecular profiling of circulating mutant DNA from small-volume "liquid biopsies" such as blood, urine, or saliva. In this article, we aim to summarize the fast-growing evidence for cfDNA and exosomal DNA as minimally invasive diagnostic markers in solid tumors and to highlight their opposing diagnostic advantages and disadvantages.
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