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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
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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