ctDNA
Also written as: ctDNA — circulating tumor DNA
Cell-free tumor DNA fragments circulating in the bloodstream that can be analyzed for cancer monitoring and diagnosis.
Full Definition
Circulating tumor DNA (ctDNA) consists of short fragments of DNA released by cancer cells into the bloodstream through processes such as apoptosis, necrosis, and active secretion. ctDNA carries the same genetic and epigenetic alterations as the tumor from which it originates, making it a valuable biomarker for liquid biopsy applications. Analysis of ctDNA enables non-invasive detection of tumor mutations, monitoring of treatment response, assessment of minimal residual disease, and identification of acquired resistance mechanisms. The amount of ctDNA in circulation generally correlates with tumor burden and can vary significantly between patients and cancer types.
Usage
Usage note: Distinguish from general cfDNA (cell-free DNA); spell out on first use.
In Context
- "Serial ctDNA monitoring revealed emerging resistance mutations during targeted therapy." — Clinical monitoring report
- "The ctDNA assay detected minimal residual disease following surgical resection." — Post-operative assessment