Imperial Medicine Blog

In the rapidly evolving landscape of healthcare, few topics have garnered as much attention and controversy as prostate cancer screening in the UK. With approximately one in six men destined to face this diagnosis in their lifetime, the urgency to address this issue is undeniable. To provide clarity amidst this complexity, Rebecca Wright, Honorary GP Teaching Fellow at the School of Public Health, and Azeem Majeed, Professor of Primary Care and Public Health, and Head of the Department of Primary Care & Public Health, at Imperial College London, delve into the heart of this debate, seeking to balance the critical factors of risks, resources, and outcomes in prostate cancer screening in England. 

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Prostate cancer screening in England has become very topical and attracted considerable recent news coverage. Around one in six men will get prostate cancer at some point in their lives with incidence increasing with age. Another major risk factor is ethnicity; black men are at highest risk of prostate cancer and Asian men are at lowest risk. Other risk factors include family history, obesity and genetics; for example, those with a fault in their BRCA 2 gene (genes that produce proteins that help repair damaged DNA) have a two times higher risk of developing prostate cancer. (1) 

There are around 12,000 deaths from prostate cancer every year in the UK with three quarters of these deaths occurring in men over the age of 75.(1) 

A recent study published in the journal BMJ Oncology (the reIMAGINE study) looked at the prostate specific antigen (PSA) blood test versus magnetic resonance imaging (MRI) as tools for diagnosing prostate cancer.(2) The findings from this study have questioned the validity of the PSA test as a screening tool for prostate cancer. The study has also re-ignited the debate over whether the UK should have a prostate cancer screening programme.  

Age (years)	Prostate-specific antigen threshold (micrograms/L)
Below 40	Use clinical judgement
40–49	More than 2.5
50–59	More than 3.5
60–69	More than 4.5
70–79	More than 6.5
Above 79	Use clinical judgement
Data from: [NICE, 2021c]

There is currently no formal prostate cancer screening programme in England. General Practitioners (GPs) in England use a personalised approach. If a patient attends without symptoms of prostate cancer but is concerned, most GPs would talk the patient through the positives and negatives of PSA testing and allow the patient to make an informed decision about whether to be tested.  

Prostate cancer screening is not recommended in the UK at present because the current PSA test is not sensitive or specific enough; it generates too many false negative and false positive results. In addition, if a patient was diagnosed with early-stage prostate cancer through screening, there is currently no single treatment which is clearly superior to other treatments in terms of outcomes.  It is also currently unclear how screening would impact prostate cancer outcomes, specifically death, directly because of prostate cancer; issues that will be considered by the UK National Screening Committee (UKNSC) when they meet to discuss six options for a national prostate screening programme.(3) 

So, is there a case for prostate cancer screening? 

Screening programmes aim to detect a disease before it causes any symptoms. Early detection and treatment of prostate cancer can lead to better clinical outcomes and also prevent complications and metastasis (the movement or spreading of cancer cells from one organ or tissue to another). The European randomised screening study for prostate cancer (4) showed a 20% reduced mortality from prostate cancer at 16 year follow up. This study also found that screening reduced development of metastatic prostate cancer by 30% as compared to the control cohort.  

It is also more cost-effective to treat early-stage disease as opposed to late-stage disease and disease which has metastasised, therefore potentially reducing the burden on the NHS at this crucial time.  Having a national screening programme for prostate cancer would also raise awareness of the disease and would educate the general population on the signs and symptoms of prostate cancer.   

What is the case against prostate cancer screening?  

Many prostate cancers are slow growing and may never cause a man to experience any symptoms or lead to death. By detecting these cancers, we might be exposing men to unnecessary treatments, and these can have considerable side effects, notably impotence and incontinence; as well as unnecessary costs for the NHS. The prostate cancer outcomes study found that at 18 months following radical prostatectomy 8% of men were troubled by incontinence and 59% of men were troubled by impotence. (5) 

In addition, the current PSA tests on average produce around 75% false positive results meaning that 75% of those with a raised PSA do not have prostate cancer. This can cause patients unnecessary anxiety and also puts patients through unnecessary biopsies (invasive internal investigations) that can cause both physical and emotional stress. Whilst MRI is now more widely used before prostate biopsy, there are still many patients who may go through unnecessary prostate biopsies. The PSA also produces around 15% false negatives meaning that 15% of those with a negative PSA will have prostate cancer. This falsely reassures patients and may lead to them ignoring symptoms of prostate cancer.  

Some low-grade prostate cancers will never cause symptoms or reduce life expectancy. The CAP randomised clinical trial found that, as compared to the control, single PSA screening did detect more prostate cancers but did not have any effect on overall mortality. (6) Hence, a prostate cancer screening programme based on a one-off PSA may lead to overdiagnosis and not have an effect on mortality from prostate cancer.  

As well as impacts on individuals, implementing a nationwide screening programme is expensive and there are also further indirect costs associated with treatment and follow up through diagnosis of cancers which may not have caused any harm to the individual. In an NHS where funding is limited, do we have the infrastructure; such as staff, MRI scanners, and drugs to support such a screening programme?  

There are many pros and cons to implementing a new screening programme, but perhaps there is a middle ground; risk-based screening. Focusing on at risk groups would mean that NHS resources could be targeted at those most likely to develop prostate cancer. This would in turn reduce overdiagnosis by not screening those with a low risk of developing prostate cancer. Alternatively, do we give patients the choice? In a similar way to how we currently practice; do we give patients the necessary information and allow them to make an informed decision about whether they would like prostate cancer screening at a given age?  

In an NHS where funding is limited, do we have the infrastructure; such as staff, MRI scanners, and drugs to support such a screening programme? The UK National Screening Committee (UK NSC) will be discussing six options for a national prostate cancer screening programme. However, to make any evidence-based recommendations, the UK NSC will need further high-quality, research that proves that screening would not only improve prostate cancer outcomes and reduce mortality but also reduce the harm caused by overdiagnosis of prostate cancer and be a cost-effective use of NHS funding. 

Conclusions 

The debate over prostate cancer screening in the UK is contentious. Early detection of prostate cancer could lead to better clinical outcomes and reduce the burden on the NHS. But the existing screening methods like the PSA test have limitations, leading to false positives that could cause unnecessary anxiety and treatment for patients; as well as false negatives that could give patients inappropriate reassurance. Moreover, the financial and logistical implications of implementing a nationwide screening programme are considerable. 

Any decision on a national screening programme must be based on high-quality, long-term research that carefully weighs both the benefits and drawbacks. Future research should focus not only on the efficacy of screening in reducing mortality but also consider the quality of life for those diagnosed with prostate cancer and the economic impact on the NHS.  

A middle ground, such as risk-based screening, could provide a more targeted approach, enabling NHS resources to be used more efficiently. Regardless of the path chosen, it is crucial that all stakeholders – from healthcare professionals to policy makers to the public – engage in an open, evidence-based dialogue to arrive at a solution that is clinically effective, cost effective and ethical. 

 

References:  

1. Prostate cancer (2023) Cancer Research UK. Available at: https://www.cancerresearchuk.org/about-cancer/prostate-cancer.  
2. Moore CM, Frangou E, McCartan N on behalf of the Re-Imagine Study group, et al Prevalence of MRI lesions in men responding to a GP-led invitation for a prostate health check: a prospective cohort study BMJ Oncology 2023;2:e000057. doi: 10.1136/bmjonc-2023-000057 
3. UK NSC annual report 1 April 2022 to 31 March 2023, GOV.UK. Available at: https://www.gov.uk/government/publications/uk-national-screening-committee-annual-report-2022-to-2023/uk-nsc-annual-report-1-april-2022-to-31-march-2023#annual-call-for-topics 
4. Hugosson J, Roobol MJ, Månsson M, et al. A 16-yr follow-up of the European randomized study of screening for prostate cancer. Eur Urol 2019;76:43–51 
5. Stanford JL, Feng Z, Hamilton AS, et al. Urinary and Sexual Function After Radical Prostatectomy for Clinically Localized Prostate Cancer: The Prostate Cancer Outcomes Study. JAMA. 2000;283(3):354–360. doi:10.1001/jama.283.3.354 
6. Martin RM, Donovan JL, Turner EL, et al. Effect of a low-intensity PSA-Based screening intervention on prostate cancer mortality: the CAP randomised clinical trial. JAMA 2018;319:883-95 

Figures:  

1. Figure 1: Prostate cancer (2023) Cancer Research UK. Available at: https://www.cancerresearchuk.org/about-cancer/prostate-cancer.  

Tables:  

1. Table 1: NICE  (2021c) Suspected cancer: recognition and referral. National Institute for Health and Care