circulating tumor DNA
DNA fragments shed by tumor cells that circulate in the bloodstream and can be detected through liquid biopsy techniques. Often abbreviated as ctDNA in medical literature.
Full Definition
Circulating tumor DNA (ctDNA) consists of short DNA fragments released by tumor cells into the bloodstream through cell death processes. These fragments carry tumor-specific genetic alterations and can be detected using highly sensitive molecular techniques such as digital PCR or next-generation sequencing. The analysis of ctDNA enables non-invasive monitoring of tumor burden, detection of minimal residual disease, tracking of treatment response, and identification of emerging resistance mutations without requiring tissue biopsies. The half-life of ctDNA is relatively short (approximately 16 minutes to 2.5 hours), making it a real-time biomarker for tumor dynamics.
Usage
Usage note: Often abbreviated as ctDNA in clinical reports. Editors should ensure consistency in abbreviation usage and proper capitalization of the full term.
In Context
- "The circulating tumor DNA analysis revealed a BRAF V600E mutation that was not detected in the original tissue biopsy." — Molecular pathology report
- "Serial monitoring of circulating tumor DNA levels showed a dramatic decrease following targeted therapy initiation." — Treatment response assessment