screening for Prostate cancer
M RavanbodMedical oncologist
Bushehr – 11/91
A 50 y/o white man comes for check up and wants to discuss about prostate cancer.
Negative family historyNo lower urinary tract symptomsWhat would you advise?
Most frequent non-skin cancerSecond leading cause of cancer death About 250,000 new cases anuallyAbout 34,000 deaths/yrAfter peaking in early 1990s about 30%
decrease till 2007After 2007 at diagnosis 80% confined to
prostate ,4% metastatic
Risk factorsOlder age
Positive family history
Black race
Median age at diagnosis is 67.
In the US 90% detected by screening
After introduction of PSA lifetime diagnosis doubled ;9% in 1985;16% in 2007
Great majority of men with a diagnosis of prostate cancer die from other causes
Autopsy data suggests 30% of men>50y and 70% >70y have occult prostate cancer.
SEER registry data90,000 prostate cancer 1992-2002Death risk from prostate cancer: 8% for well-diff. tumors 26% for poorly-diff.Death risk from other causes:60%
Screening The rationale for screening is that early
detection and treatment of asymptomatic cancers could extend life, as compared with treatment at the time of clinical diagnosis.
Effective screening requires: - an accurate,reliable,easy to
administer test that detects clinically important
cancers at a preclinical stage. -availability of effective treatment that
results in better outcomes when administered early.
For many years DRE was the primary screening test for prostate cancer
In the late 1980s PSA widely adopted for screening.
There was no evidence that testing reduced the risk of death from prostate cancer
False positive PSABPH prostatitisCystitisEjaculationPerineal traumaRecent urinary tract instrumentation or
surgery
False negativeIn prostate cancer prevention trial:
-15% of men with normal DRE and
PSA= 4 had prostate cancer
- 9% in nl DRE and PSA< 1
Approaches to improve the diagnostic accuracy of PSA testMeasuring PSA velocityFree & pr-bound PSAPSA densityUse of cutoff values for age & raceHowever,the clinical usefulness of these
strategies remains unproved.
ERSPC trial7 europian countries182,160 men between 50-74y Prostate cancer 8.2% in screen group vs
4 .8% in control groupMortality from prostate cancer was 20%
lower in screen group, not for 50-54 & 70-74 y
PLCO trialIn US , 76693 men between 55-74 yPSA & DRE annually for 6 yrs22% more cases detected in screen groupDid not show any reduction in overall or
prostate cancer mortality
US Preventive Services Task ForceRecently issued a draft recommendation
against PSA screening for asymptomatic men, regardless of their age,race or family history
The Task Force concluded that the harms of screening outweigh the benefits.
conclusionDecision about prostate cancer screening
should be based on the preferences of an informed patient.
ACS guidelinesShared decision making between patient and
physicianAge to begin: - average risk :50 (40 in AUA) - high risk (black or 1st degree relative
with prostate cancer) : 40-45 (40 in AUA)Discontinuation of screening: life expectancy
<10 yr
Screening tests: PSA , DRE(optional)Frequency : annual (every other yr if
PSA<2.5)Criteria for biopsy:PSA>4.abnormal DRE.
Individualize risk assessment if PSA = 2.5-4