TEST CODE: 008861

DIAGNOSTIC TEST FOR: CELL-FREE DNA TESTING (cfDNA)

TURNAROUND TIME: 10–21 calendar days (14 days on average)

PREFERRED SPECIMEN: 3mL whole blood in a purple-top tube

ALTERNATE SPECIMENS: DNA or saliva/assisted saliva

Cell-Free DNA Testing (cfDNA)

Cancer is a complex disease, caused by a wide range of genetic mutations. These mutations can be present in many combinations that are unique to each patient, making every case of cancer a rare disease. Current treatment protocols rely on the assumption that patients with cancer of the same tissue type have the same underlying disease. However, each tumour has a unique genetic makeup, even amongst the same tissue type. Identification of these individual mutations is the key to developing personalised treatments for cancer patients. Liquid biopsies have the potential to detect, characterise, and monitor cancers earlier in comparison to more conventional approaches.

What is ctDNA Testing?

Cell-free DNA (cfDNA) are small fragments of DNA that are released from normal cells and tumour cells by programmed cell death (apoptosis) into the blood. Tumour cells may release circulating cell-free tumour DNA (ctDNA), which may contain identical mutations to those seen identified in the primary tumour. Release of ctDNA into the blood allows for a ‘“liquid biopsy’” to be performed from a blood sample. This removes the need for invasive procedures, such as biopsies through fine needle aspiration or surgical excisions, which may be risky for the patient or not possible due to the size or location of the tumour.  ctDNA testing may give an indication of the size of a tumour or the amount of cancer cells in the body, monitor patient response to treatment and may alert doctors to early signs of recurrence or resistance.  ctDNA testing can detect early recurrences of cancer before tumours are able to be clinically or radiographically acknowledged, potentially giving doctors a larger time frame to alter treatment regimens. If a patient relapses, a liquid biopsy may reveal new mutations that were not present in the primary tumour, allowing for guidance regarding choices for second-line therapy. 

Why Should I Do ctDNA testing?

Check for residual cancer following treatment

– ctDNA is a potential marker of residual cancer cells following surgery and may determine which patients will experience recurrence. 

– Radiology and imaging techniques can detect tumours approximately 7 – 10 mm in size. ctDNA is released by tumours around 20 times smaller than this, allowing for residual cancer cells to be detected much earlier following treatment. 

– The change of ctDNA levels in response to treatment has been observed across a range of tumour types, and some studies have found increased levels of ctDNA before or at the time of recurrence.  

Monitor therapy and check for resistance

– ctDNA testing may provide an overview of all the different cells within a tumour cells released into the bloodstream. Analysis can detect new molecular changes in the cells, which may provide an early indication of resistance to therapy.

– By understanding mutations and pathways in the mutations in the tumour, personalised treatment approaches regimens can be planned. This may help reduce the development of resistance or improve response to treatment. 

– For patients currently undergoing treatment, testing may identify new treatment options.

Early Diagnosis and Detection

– Following further studies, ctDNA testing may potentially be used for cancer screening or early detection in the future.

Track the number of cancer cells in real-time

– Levels of ctDNA increase with disease progression and correspondingly decrease in response to therapy treatment. 

– The half-life of ctDNA can is less than 2 hours which can more accurately reflect the real-time tumour size and burden in patients than other cancer markers receiving therapy. ^[4]

– Tracking ctDNA levels over time can be used to monitor response to treatment. 

Ready to take control of your treatment plan?

Genomed aims to educate patients and their families on their cancer types and empower them with the knowledge to take control of their treatment plans. As each patient’s case is unique, there is no “one size fits all” when it comes to testing. We encourage you to contact Genomed, and we can work with you and your oncologist/specialist, to determine what tests would benefit you.