The most common type of prostate cancer has two different ways of developing in the body, researchers have found, opening up new possibilities for identifying which patients need treatment.
Prostate cancer is the most common form of cancer in men, with… one in eight developed the disease during their lifetime. Most prostate cancers are adenocarcinomas – a type of cancer that forms in the glandular tissue that lines certain internal organs. But while the disease can be fatal, the risk is low for many patients.
“The main problem in prostate cancer is identifying those 15% of men who will have more aggressive cancers that will spread to other organs and actually cause death,” says Prof. David Wedge from Manchester Cancer Research Centre, who led the study.
He said: “If we can identify those men, we can give them more robust treatment… and you can leave the other 85% of men alone. That is beneficial, because the operation itself has many side effects.”
Now Wedge and colleagues say they have found a new way to classify adenocarcinomas that could help them.
Writing in the diary Cell genomicsthe researchers report how they sequenced the genomes of 159 patients with prostate adenocarcinoma. They then used three different approaches – including artificial intelligence (AI) – to analyze patterns within the genomes, including the way DNA was damaged and the order in which certain genetic changes occurred.
All three approaches pointed to the same result: that the prostate cancers fell into two main groups – or ‘evotypes’ – related to how they changed in the body over time and the mechanisms involved.
Crucially, when the researchers looked at the results of blood tests taken after the patients had undergone treatment, they found that those with one evotype were twice as likely to show signs of a recurrence of the disease than those with the Others.
Wedge said: “Often those men will actually have metastasis, (so) the cancer has already spread to other organs.”
The team says the findings suggest that a genetic test could be used to determine whether patients with prostate adenocarcinoma have the more or less aggressive evotype, allowing treatment to be better tailored to them and potentially given earlier.
Wedge said it is now important to investigate whether the type of evotype may be related to factors such as the patient’s age and ethnicity, while the team is also looking at whether other cancer types have evotypes.
Prof. Joe O’Sullivan, a prostate cancer oncologist at the Northern Ireland Cancer Center in Belfast, who was not involved in the work, welcomed the study.
He said: “The identification of two different subtypes of prostate cancer along the genetic evolutionary pathway could help both stratify treatment and potentially open up new avenues for drug discovery.”