Liquid Biopsy: The Future of Non-Invasive Diagnostics
A liquid biopsy is a simple, non-invasive test performed on a body fluid (most commonly blood) that detects biomarkers shed by a tumor. It represents a major breakthrough in precision medicine, offering a way to monitor cancer in real-time without the risks and limitations of an invasive surgical tissue biopsy.
1. How It Works: Tracking the Tumor's Shedding
Instead of physically removing tumor tissue, a liquid biopsy analyzes material circulating in the bloodstream:
Circulating Tumor DNA (ctDNA): Small fragments of DNA released into the blood as tumor cells die. Analyzing ctDNA allows doctors to identify specific gene mutations (like EGFR or ESR1) that drive the cancer.
Circulating Tumor Cells (CTCs): Intact cancer cells that have broken away from the primary tumor and entered the bloodstream. Analyzing CTCs can provide insight into a tumor's ability to metastasize (spread).