Blood test that trawls samples for tiny fragments released by tumours ‘is 90% accurate at detecting aggressive prostate cancer’
- New test checks for circulating tumor cells (CTC) which have entered the blood
- London researchers found the new method spotted cancer with 90% accuracy
- It also predicted aggressiveness of cancer, removing need for painful biopsies
Thousands of men with prostate cancer may be spared painful treatments thanks to a new blood test, scientists say.
A trial of the experimental test showed it spotted the killer disease with more than 90 per cent accuracy.
Researchers discovered it was also able to predict the aggressiveness of the cancer, therefore removing the need for painful biopsies in less severe cases.
Prostate cancer is the most common cancer in men in the UK, with 47,000 men being diagnosed each year.
It usually develops slowly and the majority of cancers will not require treatment in a man’s lifetime.
But doctors currently struggle to distinguish between aggressive and less serious tumours, making it hard to decide on treatment.
Thousands of men with prostate cancer may be spared painful treatments thanks to a new blood test that detects the aggressiveness of the disease with 90 per cent accuracy (file image)
Aggressive forms of the disease require rapid treatment, but low-risk patients often do not need any treatment at all.
Experts hope the test could help men avoid unnecessary biopsies and repeated invasive follow-ups for ‘low risk’ patients.
The new test is said to detect early cancer cells, or circulating tumor cells (CTC), that have left the original tumour in the prostate and entered the bloodstream.
Current methods measure the amount of prostate specific antigen (PSA) in the blood.
PSA is a protein produced by normal cells in the prostate and also by prostate cancer cells.
It’s normal to have a small amount of PSA in the blood, and the amount rises slightly as men get older and their prostate gets bigger.
WHAT IS PROSTATE CANCER?
How many people does it kill?
Prostate cancer became a bigger killer than breast cancer for the first time, official statistics revealed last year.
More than 11,800 men a year – or one every 45 minutes – are now killed by the disease in Britain, compared with about 11,400 women dying of breast cancer.
How quickly does it develop?
Prostate cancer usually develops slowly, so there may be no signs someone has it for many years, according to the NHS.
If the cancer is at an early stage and not causing symptoms, a policy of ‘watchful waiting’ or ‘active surveillance’ may be adopted.
Some patients can be cured if the disease is treated in the early stages.
But if it diagnosed at a later stage, when it has spread, then it becomes terminal and treatment revolves around relieving symptoms.
Tests and treatment
Tests for prostate cancer are haphazard, with accurate tools only just beginning to emerge.
There is no national prostate screening programme as for years the tests have been too inaccurate.
Doctors struggle to distinguish between aggressive and less serious tumours, making it hard to decide on treatment.
Men over 50 are eligible for a ‘PSA’ blood test which gives doctors a rough idea of whether a patient is at risk.
But it is unreliable. Patients who get a positive result are usually given a biopsy which is also not foolproof.
Scientists are unsure as to what causes prostate cancer, but age, obesity and a lack of exercise are known risks.
Anyone with any concerns can speak to Prostate Cancer UK’s specialist nurses on 0800 074 8383 or visit prostatecanceruk.org
A raised PSA level may suggest there is a problem with the prostate, but it does not necessarily mean cancer.
Due to this, around 75 per cent of all PSA positive results end up with painful biopsies that do not find cancer and risk bleeding and infection.
Scientists say by measuring intact living cancer cells in the patient’s blood, rather than PSA, the new test provides a more accurate test.
The research team at the Queen Mary University of London trialled the new blood test combined with the PSA test on 253 patients at St Bartholomew’s Hospital in London.
They found that the presence of CTCs in pre-biopsy blood samples were indicative of the presence of aggressive prostate cancer.
When the CTC tests were used in combination with the current PSA test, it was able to predict the presence of aggressive prostate cancer in subsequent biopsies with over 90 per cent accuracy.
Lead researcher Professor Yong-Jie Lu said current methods often lead to an over diagnosis and over treatment in many men.
Professor Lu, from Queen Mary University of London, added: ‘This causes significant harm to patients and a waste of valuable healthcare resources.
‘There is clearly a need for better selection of patients to undergo the biopsy procedure.
‘Testing for circulating tumour cells is efficient, non-invasive and potentially accurate, and we’ve now demonstrated its potential to improve the current standard of care.
‘By combining the new CTC analysis with the current PSA test, we were able to detect prostate cancer with the highest level of accuracy ever seen in any biomarker test, which could spare many patients unnecessary biopsies.
‘This could lead to a paradigm shift in the way we diagnose prostate cancer.’
The test has to be trialled at other hospitals before it is available either privately or on the NHS, which could take three to five years.
The findings were published in The Journal of Urology.