Editing Prostate-specific antigen (section)

===Prostate cancer===

====Screening====
{{Main|Prostate cancer screening}}

[[Clinical practice guideline]]s for prostate cancer [[screening (medicine)|screening]] vary and are controversial, in part due to uncertainty as to whether the benefits of screening ultimately outweigh the risks of [[overdiagnosis]] and overtreatment.<ref name="Gomella-2011">{{cite journal | vauthors = Gomella LG, Liu XS, Trabulsi EJ, Kelly WK, Myers R, Showalter T, Dicker A, Wender R | title = Screening for prostate cancer: the current evidence and guidelines controversy | journal = The Canadian Journal of Urology | volume = 18 | issue = 5 | pages = 5875–5883 | date = October 2011 | pmid = 22018148 }}</ref> In the United States, the [[Food and Drug Administration]] (FDA) has approved the PSA test for annual screening of prostate cancer in men of age 50 and older.{{medcn|date=July 2020}} The patient is required to be informed of the risks and benefits of PSA testing prior to performing the test.{{medcn|date=July 2020}}

In the United Kingdom, the [[National Health Service]] (NHS) {{As of|2018|lc=y}} does not mandate, nor advise for PSA test, but allows patients to decide based on their doctor's advice.<ref>{{cite web | url = https://www.nhs.uk/livewell/prostatehealth/pages/psa-test.aspx | title = Should I have a PSA test? | archive-url = https://web.archive.org/web/20180228163153/https://www.nhs.uk/livewell/prostatehealth/pages/psa-test.aspx | archive-date = 28 February 2018| work = NHS Choices | date = 27 February 2018 }}</ref> The NHS does not offer general PSA screening, for similar reasons.<ref>{{cite web|title=Prostate cancer - PSA testing - NHS Choices|url=http://www.nhs.uk/Conditions/Cancer-of-the-prostate/Pages/Prevention.aspx|publisher=NHS Choices|language=en|date=3 January 2015}}</ref>

PSA levels between 4 and 10{{nbsp}}ng/mL (nanograms per milliliter) are considered to be suspicious, and consideration should be given to confirming the abnormal PSA with a repeat test. If indicated, [[prostate biopsy]] is performed to obtain a tissue sample for histopathological analysis. {{citation needed|date=May 2021}}

While PSA testing may help 1 in 1,000 avoid death due to prostate cancer, 4 to 5 in 1,000 would die from prostate cancer after 10 years even with screening. This means that PSA screening may reduce mortality from prostate cancer by up to 25%. Expected harms include anxiety for 100–120 receiving false positives, biopsy pain, and other complications from biopsy for false positive tests.{{medcn|date=July 2020}}

Use of PSA screening tests is also controversial due to questionable test accuracy. The screening can present abnormal results even when a man does not have cancer (known as a [[False positives and false negatives|false-positive result]]), or normal results even when a man does have cancer (known as a [[False positives and false negatives|false-negative result]]).<ref>{{Cite web|url=https://www.cancer.org/cancer/prostate-cancer/detection-diagnosis-staging/detection.html|title=Can Prostate Cancer Be Found Early?|website=www.cancer.org|language=en|access-date=2020-01-17}}</ref> False-positive test results can cause confusion and anxiety in men, and can lead to unnecessary prostate [[Biopsy|biopsies]], a procedure which causes risk of pain, infection, and [[Bleeding|hemorrhage]]. False-negative results can give men a false sense of security, though they may actually have cancer.{{medcn|date=July 2020}}

Of those found to have prostate cancer, overtreatment is common because most cases of prostate cancer are not expected to cause any symptoms due to low rate of growth of the prostate tumor. Therefore, many will experience the side effects of treatment, such as for every 1000 men screened, 29 will experience erectile dysfunction, 18 will develop urinary incontinence, two  will have serious cardiovascular events, one will develop pulmonary embolus or deep venous thrombosis, and one perioperative death.{{Failed verification|date=February 2020}} Since the expected harms relative to risk of death are perceived by patients as minimal, men found to have prostate cancer usually (up to 90% of cases) elect to receive treatment.<ref name="screening">{{cite web |url=http://www.uspreventiveservicestaskforce.org/prostatecancerscreening/prostatecancerscript.pdf |title=Talking With Your Patients About Screening for Prostate Cancer |access-date=2012-07-02 |archive-url=https://web.archive.org/web/20141011150935/http://www.uspreventiveservicestaskforce.org/prostatecancerscreening/prostatecancerscript.pdf |archive-date=11 October 2014 |url-status=dead }}</ref><ref name="Grossman-2018">{{cite journal | vauthors = Grossman DC, Curry SJ, Owens DK, Bibbins-Domingo K, Caughey AB, Davidson KW, Doubeni CA, Ebell M, Epling JW, Kemper AR, Krist AH, Kubik M, Landefeld CS, Mangione CM, Silverstein M, Simon MA, Siu AL, Tseng CW | title = Screening for Prostate Cancer: US Preventive Services Task Force Recommendation Statement | journal = JAMA | volume = 319 | issue = 18 | pages = 1901–1913 | date = May 2018 | pmid = 29801017 | doi = 10.1001/jama.2018.3710 | doi-access = free }}</ref><ref name="Fenton-2018">{{cite journal | vauthors = Fenton JJ, Weyrich MS, Durbin S, Liu Y, Bang H, Melnikow J | title = Prostate-Specific Antigen-Based Screening for Prostate Cancer: Evidence Report and Systematic Review for the US Preventive Services Task Force | journal = JAMA | volume = 319 | issue = 18 | pages = 1914–1931 | date = May 2018 | pmid = 29801018 | doi = 10.1001/jama.2018.3712 | doi-access = free }}</ref>

====Risk stratification and staging====

Men with prostate cancer may be characterized as low, intermediate, or high risk for having/developing metastatic disease or dying of prostate cancer. PSA level is one of three variables on which the risk stratification is based; the others are the grade of prostate cancer ([[Gleason grading system]]) and the stage of cancer based on physical examination and imaging studies. D'Amico criteria for each risk category are:<ref name="D'Amico-1998">{{cite journal | vauthors = D'Amico AV, Whittington R, Malkowicz SB, Schultz D, Blank K, Broderick GA, Tomaszewski JE, Renshaw AA, Kaplan I, Beard CJ, Wein A | title = Biochemical outcome after radical prostatectomy, external beam radiation therapy, or interstitial radiation therapy for clinically localized prostate cancer | journal = JAMA | volume = 280 | issue = 11 | pages = 969–974 | date = September 1998 | pmid = 9749478 | doi = 10.1001/jama.280.11.969 | doi-access = free }}</ref>
:Low risk: PSA < 10, Gleason score ≤ 6, AND clinical stage ≤ T2a
:Intermediate risk: PSA 10-20, Gleason score 7, OR clinical stage T2b/c
:High risk: PSA > 20, Gleason score ≥ 8, OR clinical stage ≥ T3
Given the relative simplicity of the 1998 D'Amico criteria (above), other predictive models of risk stratification based on [[mathematical probability]] constructs exist or have been proposed to allow for better matching of treatment decisions with disease features.<ref>{{cite journal | vauthors = Rodrigues G, Warde P, Pickles T, Crook J, Brundage M, Souhami L, Lukka H | title = Pre-treatment risk stratification of prostate cancer patients: A critical review | journal = Canadian Urological Association Journal | volume = 6 | issue = 2 | pages = 121–127 | date = April 2012 | pmid = 22511420 | pmc = 3328553 | doi = 10.5489/cuaj.11085 | doi-broken-date = 28 November 2024 }}{{dead link|date=November 2016}}</ref>
Studies are being conducted into the incorporation of multiparametric [[MRI]] imaging results into [[nomogram]]s that rely on PSA, Gleason grade, and tumor stage.<ref>{{cite web| vauthors = Sperling D | title = mpMRI improves the accuracy of the Partin tables and other nomograms|url=http://sperlingprostatecenter.com/mpmri-improves-the-accuracy-of-the-partin-tables-and-other-nomograms/|website=Sperling Prostate Center|access-date=31 March 2016}}</ref>

====Post-treatment monitoring====

PSA levels are monitored periodically (e.g., every 6–36 months) after treatment for prostate cancer – more frequently in patients with high-risk disease, less frequently in patients with lower-risk disease. If surgical therapy (i.e., radical prostatectomy) is successful at removing all prostate tissue (and prostate cancer), PSA becomes undetectable within a few weeks. A subsequent rise in PSA level above 0.2{{nbsp}}ng/mL<ref>{{cite journal | vauthors = Freedland SJ, Sutter ME, Dorey F, Aronson WJ | title = Defining the ideal cutpoint for determining PSA recurrence after radical prostatectomy. Prostate-specific antigen | journal = Urology | volume = 61 | issue = 2 | pages = 365–369 | date = February 2003 | pmid = 12597949 | doi = 10.1016/s0090-4295(02)02268-9 }}</ref> L{{Disputed inline|Post-treatment_monitoring:_no_references._Incorrect_units.3F|date=February 2014|reason=Should units be ng/mL?}} is generally regarded as evidence of recurrent prostate cancer after a radical prostatectomy; less commonly, it may simply indicate residual benign prostate tissue.{{Citation needed|date=February 2014}}

Following radiation therapy of any type for prostate cancer, some PSA levels might be detected, even when the treatment ultimately proves to be successful. This makes  interpreting the relationship between PSA levels and recurrence/persistence of prostate cancer after radiation therapy more difficult. PSA levels may continue to decrease for several years after radiation therapy. The lowest level is referred to as the PSA nadir. A subsequent increase in PSA levels by 2.0{{nbsp}}ng/mL{{Disputed inline|Post-treatment_monitoring:_no_references._Incorrect_units.3F|date=February 2014|reason=Should units be ng/mL?}} above the nadir is the currently accepted definition of prostate cancer recurrence after radiation therapy.{{Citation needed|date=February 2014}}

Recurrent prostate cancer detected by a rise in PSA levels after curative treatment is referred to as a "[[biochemical recurrence]]". The likelihood of developing recurrent prostate cancer after curative treatment is related to the pre-operative variables described in the preceding section (PSA level and grade/stage of cancer). Low-risk cancers are the least likely to recur, but they are also the least likely to have required treatment in the first place.{{Citation needed|date=February 2014}}