Researchers at the University of East Anglia have made an important advance in understanding genetic changes associated with terminal prostate cancer.
Findings published today in the British Journal of Cancer, and funded by the Association for International Cancer Research (AICR), show how a genetic mutation in untreated patients is linked to aggressive cancer later in life. It was previously thought that the mutation only occurred in response to therapy.
The research highlights why relapses could occur in some men following hormone therapy. And it could help identify those patients that will develop fatal prostate cancer much earlier for life-extending therapy.
Prostate cancer is the most common cancer in men in the UK, with more than 40,000 new cases diagnosed every year. Treatment options for patients diagnosed with early stage prostate cancer vary from "watchful waiting" to hormone-withdrawal therapy, radiotherapy or surgery.
Additional tests for indicators of aggressive cancer are necessary to help categorise patients so that those with a low-risk of the disease spreading can avoid unnecessary treatment, and those diagnosed with a high-risk can be targeted for more aggressive first line therapy.
Hormone-withdrawal therapy often results in a dramatic remission, however the disease invariably relapses with a resistant form of the cancer. A third of these are due to an increase in copy number of a particular gene called the 'androgen receptor'. The gene is on the X-Chromosome and so there is normally only one copy of this gene present in men. Prostate cancer thrives on male hormones, and one way that they develop to grow better is to increase the number of copies of the androgen receptor gene. This also enables the cancer to resist therapy.
Lead researchers Dr Jeremy Clark and Prof Colin Cooper from UEA's school of Biological Sciences carried out the research at the Institute of Cancer Research, London, and at UEA.
Dr Clark said: "By the age of 60, the majority of men will have signs of prostate cancer. However, only a small proportion of men will die of the disease. The question is - which of these cancers are dangerous and which are not? Deciding which cancers are going to progress and kill the patient is key to effective patient treatment."