Benefits and harms of prostate cancer tests
Current evidence about prostate cancer testing
Currently there is not enough evidence to determine whether early detection of prostate cancer using PSA test reduces cancer mortality or improves disease outcomes - although the latest evidence suggests any potential benefit is only likely to be small.
- Two recent systematic reviews conclude that the routine use of prostate cancer tests is not supported by evidence.1,2
- Two large trials in Europe and the US showed the benefit of prostate cancer testing was not outweighed by the harms associated with testing.3,4
Routine testing for prostate cancer is not recommended
Routine testing for prostate cancer using prostate specific antigen (PSA) and/or digital rectal examination (DRE ) is not recommended in Australia.5-7 However, many men receive or request prostate cancer testing with the view that early detection and treatment improves disease outcomes and has the potential to cure prostate cancer.
The latest edition of the RACGP Red Book does not recommend routine prostate cancer testing using PSA or DRE. They recommend that men who ask about testing for prostate cancer be informed about the potential benefits, risks and uncertainties and are assisted to make an informed decision.6
Prostate cancer testing may benefit a small number of men, but is likely to harm many others. If a man chooses to be tested, he should believe that the possible benefits of early detection is more important than the risk for harm.8
The balance of benefit and harm involved in testing for prostate cancer is in contrast to population screening programs for other cancers, such as the FOBT test for colorectal cancer. Read more about how these two tests compare.
Possible harms from prostate cancer testing
There are many contributing factors that could cause harm by testing for prostate cancer, some of these are outlined in the Box.
Some of the harms are a result of the variable course of the disease. There is a high prevalence of prostate cancer found at autopsy compared with the relatively low death rate from the disease. For example, 40–50% of men in their 70s were found to have incidental prostate cancer.9
Some prostate cancers are characterised by a slow rate of progression compared with most other cancers. These cancers may not require treatment because they grow slowly and do not progress sufficiently to cause harm or symptoms in a man’s lifetime.7
Other prostate cancers are more aggressive and would benefit from treatment. However, testing with PSA and/or DRE cannot distinguish cancers that are life-threatening from those that are not.
Prostate cancer is estimated to be present in 30–40% of men (aged > 50), but only approximately one in four of these cancers will result in clinical symptoms and only one in 14 will cause death.7
Early detection of prostate cancer may uncover indolent prostate cancers that would never cause harm, or symptoms in a man’s life. This is called overdiagnosis and is a potential harm caused by testing.
- Testing can detect prostate cancer early, before it causes symptoms
- Early detection of localised prostate cancer with a biopsy may increase the potential to cure cancer
- Early detection of advanced prostate cancer increases progression-free survival
- Elevated PSA levels are not specific to prostate cancer and elevated levels can cause unnecessary patient worry
- About 80% of PSA results are false positives (at a cut-off 2.5–4.0 ng/mL); thus a biopsy is needed to confirm diagnosis of prostate cancer and may cause complications
- Overdiagnosis of indolent prostate cancers is estimated to be between 17% and 50% and treatment of non–life-threatening cancers can reduce quality of life
Information for patients
Inform men who ask about prostate cancer testing about the potential benefits, risks and uncertainties of testing for prostate cancer. Assist them to make an informed decision before requesting a test. If a man requests prostate cancer testing after being fully counselled on the benefits and risks, perform both PSA and DRE.
To help facilitate a discussion with your patient, there is useful information available:
- Patient support guide: The early detection of prostate cancer in general practice – supporting patient choice
- Cancer Council Australia
- Lions Australian Prostate Cancer Website
- Andrology Australia
For more information
- Djulbegovic M, Beyth RJ, Neuberger MM, et al. Screening for prostate cancer: systematic review and meta-analysis of randomised controlled trials. BMJ 2010;341:c4543. [PubMed]
- Ilic D, O'Connor D, Green S, et al. Screening for prostate cancer: an updated Cochrane systematic review. BJU Int 2011;107:882–91. [PubMed]
- Schroder FH, Hugosson J, Roobol MJ, et al. Prostate-cancer mortality at 11 years of follow-up. N Engl J Med 2012;366:981–90. [PubMed]
- Andriole G, Crawford ED, Grubb RL, et al. Mortality results from a randomized prostate-cancer screening trial. N Engl J Med 2009;360:1310–9. [Full text]
- Australian Health Ministers' Advisory Council. Prostate cancer screening in Australia: position statement. 2010. www.cancerscreening.gov.au/internet/screening/publishing.nsf/Content/other-pop-health (accessed 22 November 2012).
- Guidelines for preventive activities in general practice (The Red Book) 8th Edition. Melbourne: Royal Australian College of General Practitioners, 2012. www.racgp.org.au/your-practice/guidelines/redbook/ (accessed 8 January 2013).
- Cancer Council Australia. National Cancer Prevention Policy: Prostate Cancer. wiki.cancer.org.au/prevention/Prostate_cancer/Screening (accessed 30 November 2012).
- Moyer VA. Screening for prostate cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2012;157:120–34.
- Breslow N, Chan CW, Dhom G, et al. Latent carcinoma of prostate at autopsy in seven areas. The International Agency for Research on Cancer, Lyons, France. Int J Cancer 1977;20:680–8. [PubMed]