The use of cell free DNA as a liquid biopsy

For a range of common cancers, a simple blood test could be taken in place of a tissue biopsy for diagnosis. The presence of a substance in the blood allows it to be used as liquid biopsy, improving the selection of anti-cancer therapies.

Tissue biopsies are when tissue samples are taken from a tumour for cancer diagnosis. It can be taken under local or general anaesthetics, so recovery time from the procedure may be required. Due to the nature or location of some tumours, tissue biopsies are not possible in all cases. Because of these reasons, an alternative method for cancer detection is required.

“Liquid biopsies” as a simple alternative for cancer diagnosis

“Liquid biopsies” may be the answer. This is diagnosis of cancer from a just a blood test. All cancer cells contain DNA mutations, and small fragments of this DNA are released into the bloodstream, termed cell free DNA or circulating tumour DNA. Since cell free DNA from cancer cells is different from the DNA in normal healthy cells, finding cell free DNA originating from tumours in blood suggests that there is a cancer somewhere in the body. This means that cancers can be detected before symptoms become evident.

This exciting research is Hope Against Cancer’s first funded Clinical Fellowship in the Centre of Excellence. The trial will involve taking biopsies from known cancers and comparing the DNA from these samples with the cell free DNA from the patient’s blood samples. If the DNA profiles match, it will support the use of blood tests in cancer diagnosis and treatment design.

This “liquid biopsy” has huge potential in identifying and treating cancer. If it is successful, patients can give a blood sample with relative ease, which can be repeated at low risk. Samples will be analysed in a much shorter period of time, allowing earlier decisions on treatment regimes. If cancers can be detected sooner they can also be treated earlier. The information could also tell clinicians what treatments might be most effective for the patient. All of this will improve patient outcomes. Described as a “holy grail” of bench to bedside research, this is a significant project for Hope.

More information (links open in a new tab):

Tissue biopsies

Liquid biopsies