Cancer patients have traces of the faulty DNA from their tumors in their bloodstream, and this can give clues about the mutations behind the cancer and the stage of the disease. This so-called "liquid biopsy" could lead to less invasive testing and better targeting of treatment.
A team of scientists, led by Cancer Research UK, looked at blood samples from 20 women with ovarian and breast cancer, zoning in on almost 20,000 possible mutations in 6 cancer-related genes. The research was published in Science Translational Medicine.
The technique was able to find the origin of a metastatic relapse in a patient with a number of primary tumors and found a mutation in the bloodstream in a patient with ovarian cancer, which was missed in the initial biopsy, because cells are not identical throughout a tumor. By looking at the DNA in the blood, the technique could also be used to track how fast the cancer is growing or how a patient is responding to treatment in "real time," allowing doctors to change treatments as needed--in the study, a woman with breast cancer was monitored for 16 months, and the blood tests accurately reflected how her tumor was progressing.
Study author Dr. Nitzan Rosenfeld, based at the Cancer Research UK Cambridge Research Institute, said: "This type of blood test has the potential to revolutionize the way we diagnose and treat cancer. The great advantage is that it can be used to identify cancer mutations without surgery or a biopsy, making it safer and cheaper."
While this technique may not completely replace biopsies, it could mean that patients do not need to have as many surgical procedures to monitor their disease.