Simple blood test tracks how men respond to prostate cancer treatment

Movember-funded scientists have uncovered a new blood test that can be used to monitor how well men with advanced prostate cancer are responding to treatment.

The test was evaluated by researchers who looked at blood samples from men with advanced prostate cancer who were having cancer treatment. 

Teams from the ICR in London and the Royal Marsden NHS Foundation Trust looked at blood samples from men with advanced prostate cancer and found that traces of cancer DNA could be detected in their bloodstream.
 
High levels of circulating tumour DNA (ctDNA) suggested that the disease would progress more rapidly, while large reductions over time indicated that treatment was working.

It could lead to tailored treatment for those in the advanced stages of the disease and help doctors decide when to stop treatments that aren’t working as well.  

This type of blood test is non-invasive and therefore less painful and more convenient than traditional tissue biopsies.

Professor Johann de Bono, professor of experimental cancer medicine at the ICR and consultant medical oncologist at The Royal Marsden, says: “Our study shows that a simple blood test could help us track how cancer evolves and responds to treatment – initially as part of clinical trials and eventually in routine care.
 
“These so-called liquid biopsy tests are minimally invasive, cost-effective and can be performed often and with ease. Tracking prostate cancer with a blood test instead of a painful surgical biopsy could significantly improve patients’ quality of life.”

The study looked at blood samples from men who were part of a clinical trial of the drug abiraterone with or without an experimental drug called ipatasertib.

The results showed that men with high levels of circulating tumour DNA (ctDNA) at the start of treatment had a significantly worse outcome.

Dr Mark Buzza, global director of prostate cancer biomedical research, says: “The results of this study are extremely exciting as they demonstrate that ctDNA can act as a potential biomarker to better understand patient prognosis, monitor cancer progression and interpret emerging treatment resistance mechanisms.”

The research, which was presented at the American Society of Clinical Oncology virtual conference was sponsored by Roche and Genetech and received funding from Movember and other cancer charities.