New research shows that regular blood tests could help patients with prostate cancer to improve their long-term survival chances.
Blood tests can be done before and after chemotherapy to help doctors determine if a patient has developed resistance to docetaxel, a widely-used drug.
They may be able to change the patient’s treatment without having to perform painful biopsies.
Docetaxel is a treatment that significantly increases survival rates for prostate cancer patients who have spread to other areas of their bodies.
Doctors could conduct blood tests prior to and during chemotherapy in order to determine if their patient has developed resistance or is responding well.
Barts Cancer Institute, Queen Mary University of London conducted a new study that examined blood markers for cancer known as “circulating tumor cells” (CTCs).
CTCs refer to cancer cells which have reached the bloodstream either from the initial cancer site, or tumours surrounding the area where it has spread.
They collected blood from 56 men with advanced prostate cancer being treated at St Bartholomew’s Hospital, London.
Samples were collected over six- to eight months. They covered time between the start of docetaxel treatment and their last dose.
They looked specifically at patterns among the data of men who received treatment for their cancer and those who didn’t. Also, which type of cancer was advanced?
The results showed that men with more than six CTCs in their bloodstreams before receiving their second dose of chemotherapy were at greater risk for their illness. They also had a higher chance of dying within the first 18 months.
However, those with fewer than six CTCs in 7.5ml blood had the best chance of surviving for at least 17 months. They also had an average survival rate of 3 years.
CTCs that were high at the close of treatment indicate that patients are more likely to die sooner and have a greater chance of spreading their disease.
Caitlin Davis, the lead researcher of the study said, “Using these patterns we can apply them future patients with the aim to predict if they will respond therapy and pre-emptively determine the best course to have maximum benefit.
“For instance, an increased number of CTCs may be indicative that treatment is ineffective.
“Furthermore we monitor the appearance of drug-resistant CTCs so that treatment options can be changed early. This allows us to change treatments in a personalized and timely way.
Tissue biopsies, which are taken from the tissue of the prostate and other body parts, can currently be used to determine how advanced it might have become. These can be very painful and can take as long as 10 days to get results.
CTCs can be detected in blood samples using a liquid biopsy. The process is quick and painless.
Now, the scientists plan to examine how they could conduct a clinical study on patients in order to validate their results.
Hashim Ahmed is the chairperson of the NCRI Prostate Group and professor of Urology at Imperial College London. He said that these promising results could change clinical practice if further research confirms them.
The ability to assess the tumor’s responsiveness to chemotherapy by using blood tests allows clinicians and other healthcare professionals to customize cancer treatment without the need for invasive procedures, such as tissue biopsy.
It could help patients avoid having to go through painful systemic treatments which are likely to fail.