Circulating Tumor Cells and Cell-Free DNA/RNA Liquid Biopsies vs. Traditional Tissue Biopsy to Improve Cancer Screening: A Scoping Review

Abstract

Introduction: The goal of cancer screening is to maximize the likelihood of successful treatment outcomes for affected patients and prevent cancer development in the general public. Delays in diagnosis or barriers to accessing care are associated with lower survival rates, increased treatment-related complications, and higher healthcare costs. Liquid biopsies, particularly blood-based cell-free DNA/RNA and CTC liquid biopsies, offer a promising, less invasive alternative to traditional tissue biopsies, supporting cancer diagnostics, disease monitoring, and informing treatment decisions by providing comprehensive blood-based genetic data and early detection capabilities.

Methods: A literature search was conducted on the use of cfDNA/cfRNA and CTCs in liquid biopsies for cancer detection, recent advancements, and their efficacy compared to traditional cancer screening methods, such as tissue biopsies.

Results: Traditional screening techniques like mammography, colonoscopy, CT scans, and tissue biopsies are often invasive or limited to isolated tumors, while liquid biopsies offer a minimally invasive method to detect one or more cancer types from a single blood draw, providing real-time cancer characterization and continuous monitoring. Despite their potential advantages, liquid biopsies are not yet widely accepted as replacements for tissue biopsies, which remain the standard for initial tumor diagnosis and staging, and are limited in sensitivity for detecting certain cancers that do not shed sufficient genetic material into the bloodstream.

Discussion: Liquid biopsies offer significant advancements in personalized medicine by providing detailed molecular profiles of tumors, guiding targeted therapies, and enabling precise, individualized treatment plans. Additionally, point-of-care liquid biopsy tests have the potential to make cancer screening more accessible and convenient, especially in low-resource settings, by allowing rapid, on-site analysis with reduced healthcare costs.

Conclusion: CTC and cfDNA/cfRNA liquid biopsies offer a transformative approach to cancer screening by detecting blood-based cancer biomarkers. They provide a non-invasive, real-time snapshot of tumor heterogeneity, aiding in early cancer detection, continuous monitoring, and informing treatment response, though further research and technological advancements in liquid biopsy sensitivity are needed for full clinical integration.