David Cameron has become the latest senior figure to back growing calls for the NHS to start testing men, or at least those most at risk, for prostate cancer after he was treated for it himself.
He joined Olympic cycling champion Chris Hoy and prostate cancer charities in saying recent advances in diagnosing the disease meant testing could be much safer than traditional methods, which can produce both false positives and false negatives.
The UK National Select Committee will meet on Thursday to discuss the latest findings on the matter. The independent committee, which advises ministers, is under pressure to allow testing to begin for those men who are most at risk: black men, those with a family history of prostate, breast or cervical cancer, and men carrying the BRCA1 or BRCA2 gene.
What is prostate cancer, what are its symptoms and which populations are most at risk?
Prostate cancer develops in the prostate gland.
This second most common cancer in the UK following breast cancer: there are around 55,300 new diagnoses and 12,200 deaths each year. This is the most common cancer in men. Almost 80% of men with this diagnosis live at least 10 years.
In its early stages, it often has no symptoms. But changes in men's urinary habits—for example, the need to urinate more frequently, including at night—may indicate its presence, as can erectile dysfunction.
It mainly affects men over 50 years of age. But three groups of men are most at risk: black men; those with a family history of prostate cancer or breast or ovarian cancer in a female relative; and men carrying variants of the BRCA1 or BRCA2 gene.
Black men are twice as likely to develop the disease and die from it. A quarter of black men will be diagnosed with prostate cancer in their lifetime, compared with one in eight in the general male population.
Black men in England too they are more likely to be diagnosed with advanced prostate cancer than their white counterparts.. Socioeconomic circumstances and genetics are thought to be contributing factors to the significant increase in risk.
How is prostate cancer detected?
All men over 50 can have a PSA test to check if they have prostate cancer. These men, and those at higher risk, can talk to their GP about the pros and cons of taking the test.
GPs no longer need to assess a man's prostate through a rectal examination. Men who are at higher risk have historically been offered a biopsy, in which a needle is inserted into the prostate.
The PSA test checks the level of prostate specific antigen (PSA) in the blood. Other conditions can cause PSA levels to rise, including prostate enlargement and prostatitis, not just prostate cancer.
Unlike smear tests for cervical cancer and mammograms for breast cancer, the PSA test itself is not a test for prostate cancer. This is useful, but not definitive.
Although any man can ask his GP for a test, and GPs usually refer anyone over 50 who requests one, routine PSA testing is not offered on the NHS. This is because total PSA testing can lead to overdiagnosis of prostate cancer and result in men having to undergo unnecessary biopsies and invasive treatments, including surgical removal of the prostate.
For example, some studies have shown that Black men may have higher PSA levels than their white counterpartsand that using the PSA test in men without prostate symptoms does not reduce the number of deaths from prostate cancer.
Why doesn't the NHS test men for prostate cancer?
In the UK, people are routinely screened for breast, bowel and cervical cancer, but not prostate cancer, despite its prevalence.
Screening for it is not as easy as for other cancers due to the historical shortcomings of the PSA test (the potential for both false positives and false negatives) and the historical lack of alternative screening methods.
The UK's National Screening Committee (NSC), independent experts who advise ministers, is due to decide on Thursday whether the National Health Service should start testing either all men or those in some or all three high-risk groups for the disease.
In recent months it has come under intense pressure to rethink its stance on screening. He spent months collecting and analyzing evidence.
Charities such as Prostate Cancer UK and Prostate Cancer Research say the NSC should at least endorse targeted screening of men in the three high-risk groups. According to them, this would allow more cases of the disease to be identified and thereby save more lives.
Lithuania (2006), Kazakhstan (2013) and Sweden (2020) have already introduced screening for many or all male citizens aged at least 50 years.
What are the arguments for and against targeted prostate cancer screening?
Prostate Cancer Research insists that recent advances in diagnostic testing mean screening can be introduced with far fewer risks than those associated with the PSA test.
Men can be safely screened with a PSA test followed by an MRI before a biopsy – “which rules out cancer in a large number of cases” – and then, if necessary, a transperineal biopsy, sparing many of them the rigor and risk of a traditional biopsy.
“The main security objection to the review was essentially taken out of the system,” it said.
Prostate Cancer UK agrees. “We believe the data shows that screening men at highest risk is safe and more beneficial than the harm that could be caused by a screening program,” said Chiara De Biase, director of Health, Equity and Improvement.
“MRI before biopsy improves the detection of clinically significant prostate cancer and reduces the risk of diagnosing cancer that does not require treatment. We hope the committee agrees and are urgently awaiting the results,” the charity said in a statement.
However, other organizations, notably Cancer Research UK, argue that there is still too much “conflicting evidence” about screening to justify even a targeted programme. “The evidence for targeted screening is still very unclear,” says Nasser Turabi from CRUK.
What might a prostate cancer screening program look like?
TRANSFORM Prostate Cancer Screening Study may give the answer. The £42 million study is the largest and most ambitious study into prostate cancer screening in 20 years.
The aim of the project is to find the most effective and least harmful methods of screening the adult male population of the UK and detecting the disease in its early stages. Three hundred thousand people will be involved in the trial.
It is led by Prostate Cancer UK and is due to report in 2027. The NSC agreed to reconsider prostate cancer screening in light of the TRANSFORM results. The National Institute for Health and Care Research is covering £16 million of the £42 million.
The study will also look at how modern testing methods, including PSA blood tests, genetic saliva tests and MRI, can be used more effectively in screening for the disease.
Dr Sam Merriel, from the Center for Primary Care and Health Services Research at the University of Manchester, said: “To find better ways to screen for prostate cancer than relying on PSA alone, more definitive evidence is urgently needed using modern approaches to prostate cancer screening that include newer tests including prostate MRI and genetic testing.”
