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Explore the evolving role of PSA in prostate cancer management, from monitoring treatment outcomes to predicting relapse risks. Learn about screening controversies, global practices, and novel screening strategies. Find out about PSA's limitations and new screening modalities being researched.
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PSA(Prostate Specific Antigen)- what’s new Tom Pickles Professor, Radiation Oncology, UBC Radiation Oncology Program, BC Cancer Agency
Summary • Where PSA has established a useful role • Monitoring treatment outcomes • To predict treatment outcomes • Where the use is less clear • In population screening
PSA after treatment • Cured with surgery
PSA after treatment • Cured with seeds
PSA after treatment • PSA bounce
Improvements in outcome 2004 1994 p=0.013
PSA relapse Brachy 95% EBRT 75% p=0.0008
PSA after treatment • Relapse
PSA after treatment • PSA relapse and risk of dying of prostate cancer
Predictive power of PSA • The PSA doubling time is the key. D’Amico et al., Journal of the National Cancer Institute, Vol. 95, No. 18, September 17, 2003
Now, where PSA is not so good • The Screening controversy
Significant overlap No PSA level free of cancer risk Holmström,BMJ 2009;339:b3537
PSA: No safe level Thompson. JCO VOLUME 23 NUMBER 32 NOVEMBER 10 2005
The underlying problem • PSA is not a great test! Receiver Operating Characteristic Curve for PSA Numbers on curve represent PSA cut points. AUC=0.67 Hoffmaan, BMC Fam Pract. 2002; 3: 19.
Prostate cancer in Canada Incidence Canadian Cancer Society Stats 2014
Prostate cancer in Canada Incidence Canadian Cancer Society Stats 2014
PSA screening practices in Canada ~55% have had a PSA in the last 5 years CCHS 2003
Screening trials: 3 proper ones • Europe • few had PSA test before • control patients unaware of study • Urologist handled abnormal result • USA • most had PSA tests before • Patient randomized 50/50 • family doc handled the results • UK • few had PSA test before • GP practices randomized • Patient counseled first
Cumulative number of deaths Study year of death Screening trials: 3 proper ones • Europe • USA • UK
How many benefit? • For every 1000 men screened • How many have an abnormal PSA? • How many have prostate cancer diagnosed? • How many will live longer as a result?
US Services Taskforce infographic http://www.cancer.gov/ncicancerbulletin/112712/page12
US Services Taskforce infographic http://www.cancer.gov/ncicancerbulletin/112712/page12
US Services Taskforce infographic http://www.cancer.gov/ncicancerbulletin/112712/page12
US Services Taskforce infographic http://www.cancer.gov/ncicancerbulletin/112712/page12
US Services Taskforce infographic http://www.cancer.gov/ncicancerbulletin/112712/page12
Governmental recommendations • The USPSTF recommends discussing screening for prostate cancer. • 2017: “Grade C” recommendation • Canadian Task Force on Preventive Health Care • 2014: recommendations recommend against (Grade “D” recommendation) • NHS (UK) • Do it if patient wants • Australia • Do not offer
Prostate cancer in Canada Incidence Deaths Canadian Cancer Society Stats 2014
Prostate cancer in Canada Deaths down 45% Since 1995 Canadian Cancer Society Stats 2014
New ways of screening • Baseline test in mid 40’s • Then adapt screening intensity • E.g. PSA <0.5 • check again at 50, if <1 • Check again at 60, if <1 then stop • If PSA >1 • Repeat annually to 50 • If rising, consider biopsy
PSA testing at 45-50 yrs • Risk of advanced cancer especially predicted • But beware of false positives • infection, ejaculation etc Ulmert BMC Medicine 2008, 6:6
New tests • Not there yet • PCA3 • ProPSA • PSA density • Free PSA • hK2