Cancer diagnostics are changing. For decades, a tissue biopsy — the surgical removal of a small piece of tissue from a suspected tumour — was the only reliable way to confirm a cancer diagnosis or understand how a tumour was behaving. That is no longer the case.
Liquid biopsy is a rapidly advancing approach to cancer detection and monitoring that uses a simple blood draw in place of an invasive procedure. It is faster, far less uncomfortable for patients, and may capture different biological information.
Here is what you need to know.
What is a liquid biopsy?
A liquid biopsy is a test performed on a blood sample to detect cancer-related material circulating in the bloodstream. When tumour cells grow, divide, or die, they shed biological material into the blood. A liquid biopsy captures and analyses this material to give real-time information about what is happening inside the body.
There are two primary types of material a liquid biopsy can detect:
• Circulating tumour DNA (ctDNA): Fragments of genetic material released by tumour cells into the bloodstream. ctDNA analysis can detect cancer-associated mutations, copy number alterations, and epigenetic changes.
• Circulating tumour cells (CTCs): Whole cancer cells that have broken away from a tumour and entered the bloodstream. CTC analysis can reveal the morphological and biological characteristics of tumour cells, providing a deeper understanding of how they behave and may respond to treatment over time.
How does it work?
The process begins with a standard blood draw — no different to a routine blood test. The sample is then processed in a laboratory to isolate relevant material. ctDNA and CTC analysis provide different information, which when brought together, can reveal a whole story over time of a tumour’s characteristics and behaviour.
How is this different from a tissue biopsy?
A tissue biopsy removes a sample from one location within a tumour. This provides a snapshot of that specific area. The problem is that tumours are not uniform — different regions can carry different genetic profiles, and cancer may already have spread elsewhere in the body. A liquid biopsy analyses material circulating throughout the body’s bloodstream at the time of sampling.
Liquid biopsy also has a significant practical advantage. Tissue biopsies are invasive procedures that carry risks and require recovery time. A blood draw can be repeated regularly with minimal burden to the patient, making it far better suited to ongoing monitoring.
What can liquid biopsy be used for?
• Early cancer detection — identifying the presence of cancer before symptoms appear
• Diagnosis support — providing additional biological information alongside imaging
• Treatment monitoring — tracking whether a tumour is responding to therapy
• Recurrence surveillance — detecting the return of cancer after treatment has ended
Where does Frontier Diagnostics fit in?
At Frontier Diagnostics, our focus is circulating tumour cell detection. We believe CTC analysis together with ctDNA analysis represent the most clinically meaningful applications of liquid biopsy technology — not just because of what this integrated approach can detect, but because of the quality of information provided.
Our Sentinel qCTC™ platform analyses living, intact circulating tumour cells from a routine blood draw — without enrichment — using automated fluorescence imaging and AI-driven morphological analysis.
Liquid biopsy is opening new possibilities alongside tissue biopsy – not replacing it, but extending what clinicians can see and when.
Liquid biopsy is expanding what is clinically possible- and the evidence base is growing.