Point counterpoint in PCa screeningPresentation Transcript
G. Pourmand MD. Tehran University of Medical Sciences May- June 2008 Point counterpoint: Prostate cancer in the elderly man: Should we screen men after age 65 years?
Yes No Is prostate cancer a health care problem?
Is cancer prevalence important? Health planning Benefits and Harms Most are small, confined
Cancer Incidence Rates * for Men US, 1973-1999
When Does Screening Detect Cancer? 9 years before clinical presentation
What about the prognosis?
Screen- Detected Prostate Cancer
Conventionally Presenting Localized Disease
P.W. Nicholson, BJU International
To Screen or Not !
• Serious Public Problem.
• Asymp. Localized Phase
and Predictive Values
• The Potential for Cure
• Improved Outcomes Relation to
Cost- effectiveness Avoid detecting biologically unimportant cancers Detect and treat tumors Progress, Produce Symptoms and Reduce Life Expectancy
American Cancer Society Modification (Men who eligible for Pca Screening) PSA and DRE Annually Should or Offer?
American Academy of Family Physician And US Preventive Services Task Force Do not Recommend Routine Screening in Low- Risk Patients
National Screening 1996 Counseling Potential Harms Benefits Scientific Uncertainties
Patient- Clinician Process ( Joint Decision Making) and (Agree on a Course of Action)
PSA and DRE from 50 years Life expectancy of at least 10 years Discussion
PSA < 2 ng/ml Biannually PSA ≥ 2 ng/ml Annually
Most useful tumor marker
in Prostate Epithelial Cells
BPH Prostatitis Prostatic Infarction Is PSA Ideal Tumor Marker?
PSA thershold = 4 ng/mL: 65% F. Positive rate 20% F. Negative rate PSA: 3 ng/mL Sensitivity Positive Predictive Value
PSA Density PSA Velocity Age Specific Reference May Increase Sensitivity and specificity
Age Specific PSA, Reference Range Age, yr Reference Range, ng/ml 40-49 …………………….. 0.0-2.5 50-59 …………………….. 0.0-3.5 60-69 …………………….. 0.0-4.5 70-79 …………………….. 0.0-6.5
Use of PSA and PSA density to detect prostate cancer in men with normal DRE PSA density (Threshold) Sensitivity % Specificity % Positive Predictive Value % 0.10 …………… 95 24 29 0.15 …………… 79 50 34 0.30 ……………. 45 85 50 0.50 ……………. 29 95 65
Correlation Between PSA and Prostate Cancer
Total PSA (ng/mL) PSA Density= Total prostate volume (mL)
PSA Velocity PSA ≥ 0.75 ng/mL
Digital Rectal Examination • Detect missed Pca by PSA Screening • Able to detect asymptomatic patient • Abnormal DRE (3.2%-10%) • Pca (0.2%-1.7%) in original group
ACS DRE + Occult Blood >40 yrs The (+ve) Predictive Value 17.8% Sensitivity of DRE: 53.2% Specificity of DRE: 83.6%
Trans Rectal UltraSonography Expensive Not available for family physicians Suffers from lack of specificity
Biopsy 1- Elevated PSA + Benign DRE TRUS Visible abnormal lesions 2- Abnormal DRE + TRUS Regardless of PSA
Charecteristics of Screening Tests Test Sensitivity % Specificity % Positive Predictive Value % DRE 45-58 96-97 24-58 TRUS 71-91 89-94 15-43 PSA > 4 ng/ml 67-89 59-97 33-47
1 Andorra 83.53 2 Macau 82.35 … . 47 United States 78.14 … 130 Iran 70.86 … 222 Angola 37.92 223 Swaziland 31.99 World’s Life expectancy report
Population Pyramid for USA
Population Pyramid for Iran
Points Age-specific Incidence Rate of Prostate cancer per 100,000 Population in Iran (2005-2006)
Prostate cancer screening remains widespread, despite recommendations against routine screening by the United States Preventive Services Task Force and the ACP, and recommendations by the AAFP for counseling about the known risks and uncertain benefits of screening for prostate cancer.
Recent evidence shows that men older than 75 years are frequently screened for prostate cancer, despite current guidelines suggesting they are unlikely to benefit from treatment as the disease develops slowly in this age group.
In a national surveys of physician-reported information carried out from 1999 to 2002 by Duke University Medical Center researchers:
They concluded that
Urologists were more likely to initiate the tests than non-urologists.
Excessive PSA testing has direct and indirect costs, and reflects an inefficient allocation of resources.
In another National Ambulatory Medical Care Surveys performed in 1995-6: