The most common type of prostate cancer has two distinct 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 diagnosed with 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 kill, for many patients the risk is low.
“The key problem in prostate cancer is identifying those 15% of men who will have more aggressive cancers that will spread to other organs and that will actually cause death,” said Prof David Wedge of 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 alone the other 85% of men. That is beneficial because the surgery itself has a lot of side effects.”
Now Wedge and colleagues say they have found a new way to classify adenocarcinomas that might help them do just that.
Writing in the journal Cell Genomics, the researchers report how they sequenced the genomes of 159 patients with adenocarcinoma of the prostate. They then used three different approaches – including artificial intelligence (AI) – to analyse patterns within the genomes, including the way in which DNA was damaged and the order in which certain genetic alterations occurred.
All three approaches pointed to the same result: that the prostate cancers fell into two main groupings – or “evotypes” – that related to how they changed in the body over time and the mechanisms involved.
Crucially, when the researchers looked at the results from blood tests taken after the patients underwent treatment, they found those with one evotype were twice as likely to show signs of a recurrence of the disease than those with the other.
Wedge said: “Often those men will actually have metastasis, [so] the cancer has already spread to other organs.”
The team say the findings suggest a genetic test could be used to determine whether patients with adenocarcinoma of the prostate have the more, or less, aggressive evotype, allowing treatment to be better tailored to them, and potentially given sooner.
Wedge said it is now important to explore whether the type of evotype might be associated with factors such as the age and ethnicity of the patient, while the team is also looking at whether other types of cancer have evotypes.
Prof Joe O’Sullivan, a consultant prostate cancer oncologist at the Northern Ireland Cancer Centre in Belfast, who was not involved in the work, welcomed the study.
He said: “The identification of two different sub-types of prostate cancer according to the genetic evolution pathway could help with both stratification of treatment as well as potentially opening up new possibilities for drug discovery.”
