Genetic screenings of the general population for prostate cancer are feasible, safe, and may be effective at identifying the disease in apparently healthy men who might otherwise remain undiagnosed, according to data from a pilot study in the United Kingdom.
Study findings were presented in the oral presentation, “BARCODE 1: A pilot study investigating the use of genetic profiling to identify men in the general population with the highest risk of prostate cancer to invite for targeted screening,” at the 2020 American Society of Clinical Oncology (ASCO) Virtual Scientific Program.
The study, resulting from a collaboration between The Institute of Cancer Research, The Royal Marsden NHS Foundation Trust, and general practitioners (GPs) across the country, was the first to investigate the feasibility of a genetic screening for prostate cancer in the general U.K. population.
During the study, which was funded by the European Research Council, along with Cancer Research UK and the National Institute for Health Research, investigators isolated DNA from saliva samples taken from 307 men, ages 55–69.
After isolating DNA from study participants, researchers analyzed it to look for changes in 130 loci that had been associated previously with an increased risk for prostate cancer. (Loci are specific locations on chromosomes where a gene or other types of DNA sequences are located.)
Based on information from each of those 130 loci, investigators calculated a polygenic risk score (PRS) for all study participants, which reflected their overall risk of developing prostate cancer. This also allowed them to create risk categories representing the different degrees of prostate cancer risk seen in the population.
Following these analyses, investigators selected the 26 men who were placed into the highest risk category to perform additional screening tests. Of those, 18 accepted the opportunity to have a prostate biopsy and MRI scan.
Seven of the 18 seemingly healthy men were diagnosed with prostate cancer. In all cases, the mean score of the prostate-specific antigen (PSA), a marker of prostate cancer, was 1.8, which is associated with a low-risk cancer. All men were managed with active surveillance.
“We showed that genetic barcoding of men can safely and effectively identify those at the highest level of risk for prostate cancer, so they can be targeted for follow-up checks,” Rosalind Eeles, PhD, said in a press release. Eeles is a professor at The Institute of Cancer Research, consultant at The Royal Marsden NHS Foundation Trust, and leader of the study.
Remy Smits, age 59, was one of the men participating in the pilot study who was placed in the highest risk category and later found to have a tumor the size of a grain of sand.
“Whilst the realization that I have cancer came as a shock; I feel better knowing that it has been identified at a very early stage,” he said. “I also feel that I am now in a much better position to make an informed decision about any future treatment options. I also like the fact that being part of this trial will make a difference for many men in the future.”
Following the successful completion of this pilot study, investigators now intend to launch a larger screening study, called BARCODE-1 (NCT03158922) that is expected to enroll about 5,000 men from 70 GP sites.
Investigators hope BARCODE-1 (not yet recruiting) will provide evidence of the value offered by these large population genetic screenings, which may be more effective than standard PSA testing at detecting potentially aggressive cancers.
“Our hope is that the larger BARCODE-1 pilot study will now be able to definitively show that population genetic screening for prostate cancer can cost-effectively improve diagnosis and ultimately save lives,” Eeles said.
“This is an exciting early pilot study which for the first time in the U.K. demonstrates that genetic screening for prostate cancer is safe, feasible and potentially effective. It’s great to see that this research is now progressing into a larger-scale pilot, which if successful could show the potential of genetic screening to be a life-saver,” said Paul Workman, chief executive of The Institute of Cancer Research.