prostate cancer screening dan o’connell, md dept of family medicine 2/4/05

PROSTATE CANCER SCREENING

• Dan O’Connell, MD

• Dept of Family Medicine

• 2/4/05

MEN’S HEALTH AND DISPARITIES

• Higher income

• Dominate decision making roles in society

• 10 times more likely to commit DV

• Male MDs interupt more than female MDs

• Die 5-6 years sooner (74.4 vs 79.8)

• Do not seek out preventive medical care

Cancer Morbidity/Mortality, 2001

• Incidence

• Lung 172,000 • Colo-rectal 184,000

• Breast 214,000

• Prostate 232,000• Pancreas 32,200• Melanoma 60,000

• Cervical 10,400

• Deaths

• Lung 163,000• Colo-rectal 56,000

• Breast 40,000

• Prostate 30,000• Pancreas 31,800• Melanoma 8,000

• Cervical 3,700

Prostate CA facts

• 10% of men will have symptomatic disease in their lifetime

• 4% die from prostate cancer

Spectrum of disease

• End stage prostate CA – bone mets to lumbar spine, very painful, urine, stool incontinence, possible paralysis

• Benign prostate CA –Microscopic, inconsequential, found in 30% autopsies, 70% over age 80

PROSTATE CANCER- HETEROGENEITY

• Widely varying growth rates

• Widely varying potential to cause mortality

• Screening poorly differentiates clinically significant tumors from insignificant

Case 1

• 61 yo man with HTN, DJD knees heard on the radio that he should get his PSA checked

• What do you advise?

Case 2

• 44 yo African American notes his father died of prostate cancer at age 61

• He asks if he should be checked for this

* For men in their 50s, about 50; for men in their 70s, about 270.† For men in their 50s, about 150; for men in their 70s, about 400.‡ For men in their 50s, about 17; for men in their 70s, about 90.§ For men in their 50s, about 30; for men in their 70s, about 100.¦ For men in their 50s, about 12; for men in their 70s, about 63.** For men in their 50s, about 21; for men in their 70s, about 70.

Yield of PSA, Men in their 60s

Biopsies

• 4-6 biopsies obtained from different parts of glands, focusing on area of mass if found on DRE

• Sensitivity of biopsies (based on repeat biopsies) : 70-90%

Gleason Score• Tumors graded 1-5 based on cells and

architecture

• How is the Gleason score calculated?

Gleason Score• Tumors graded 1-5 based on cells and

architecture

• Primary and secondary

• Gleason 2-4 - well differentiated low grade

• Gleason 5-7 – Moderately Differentiated

• Gleason 8-10 – Poorly differentiated, high grade

How is prostate cancer staged?

Bone Scans

• PSA % positive bone scans

• <10 2.3%

• 10-19 5.3%

• 20-50 16.2%

• Recommended for PSA >10 or Gleason 7 or more

CT scans

• For extra capsular tumors

• 244 men with PSA <15, Gleason 2-7, T2b or less: all had neg CT (Lee, Int J Radiat Oncol

Biol Phys, 12/00)

Prostate Screening Guidelines American Cancer Society - 1993

• Annual DRE beginning at 40

• Annual PSA– beginning at 40 for

• African Americans

• Family history of prostate cancer

– beginning at 50 for all other menAmerican Cancer Society, 1993

Prostate Screening Guidelines American Urological Association-1995

• “Patients in these age/risk groups should be given information about these tests and should be given the option to participate”

Prostate Screening Guidelines American Cancer Society - 2001

PSA and Digital Rectal Examination should be offered annually, beginning at age 50 years, to men who have at least a 10-year life expectancy .... Information should be provided to patients regarding potential risks and benefits of intervention.

American Cancer Society

An Evidence TableAn Evidence Table

PSA velocity

• For PSA between 2.5 and 4.0:

• “An increase of > 0.75 ng/ml per year may be 90% specific for CA (cancer) detection.”

Age / PSA cut-off value (ng/ml)

• 40 - 49 / 2.5• 50 - 59 / 3.5• 60 - 69 / 4.5• 70 - 79 / 6.5

• If there is cancer: PSA increases 2.2 for every 1 gram of cancer

External factors effecting PSA

• FALSE ELEVATION

• DRE• Prostatitis, • BPH• Urinary retention• Ejaculation within 48

hours

• FALSE DECREASE

• Finasteride (proscar)• Saw palmetto

AAFP PSA Decision Aid Men in their 60s

http://www.aafp.org/clinical/tools/

Sensitivity, Specificity, Pos Pred Value, Neg Pred Value

+

Prostate CA

No

Prostate CA

PSA >4 3

True +

7

False +

PSA <4 1

False -

89

True -

Sens, Spec PPV, NPV

• Sensitivity = a/ (a+c) = 3/4 = 75%

• Specificity = d/(b+d) = 89/96 = 93%

• PPV = a/ (a+b) = 3/10 = 30%

• NPV = d/ (c+d) = 89/90 = 99%

What are the possible disadvantages of having a PSA

test?

AAFP PSA Balance Sheet

http://www.aafp.org/clinical/tools/

Cancer Morbidity/Mortality, 2001

• Incidence

• Lung 172,000 • Colo-rectal 184,000

• Breast 214,000

• Prostate 232,000• Pancreas 32,200• Melanoma 60,000

• Cervical 10,400

• Deaths

• Lung 163,000• Colo-rectal 56,000

• Breast 40,000

• Prostate 30,000• Pancreas 31,800• Melanoma 8,000

• Cervical 3,700

AAFP PSA Balance Sheet

http://www.aafp.org/clinical/tools/

Prostate Screening Harms AUA Guideline

www.guidelines.gov

Prostate Screening Harms USPSTF Guideline

Prostate Screening Harms ACS Guideline

Summary of RecommendationsThe U.S. Preventive Services Task Force

(USPSTF)• www.ahrq.gov• The evidence is insufficient to recommend for or against

routine screening for prostate cancer using prostate specific antigen (PSA) testing or digital rectal examination (DRE). Rating:

• I recommendation.

• Rationale: The USPSTF found good evidence that PSA screening can detect early-stage prostate cancer but mixed and inconclusive evidence that early detection improves health outcomes. Screening is associated with important harms, including frequent false-positive results and unnecessary anxiety, biopsies, and potential complications of treatment of some cancers that may never have affected a patient's health. The USPSTF concludes that evidence is insufficient to determine whether the benefits outweigh the harms for a screened population.

Strength of Recommendations

A. Good evidence to support

B. Fair evidence to support

C. No recommendation for or against.

D. Fair evidence to exclude

I. Insufficient Evidence to recommend for or against

TREATMENT – RADICAL PROSTATECTOMY

• Treatment in 1/3 of all cases

• Treatment in 1/2 of cases in men <75

10 YEAR SURVIVAL

Radical prost.

Radiation therapy

Watchful waiting

Well diff 94 90 93

Mod diff 87 77 76

Poorly dif 67 53 45

Lu-Yao GL, Yao ,Lancet 1997;349:906-910.

 HARM

Men with ReducedSexual Function

Men withUrinary Problems

Men withBowel Problems

Men withOther Problems

Treatment

Radical Prostatectomy

20%-70% 15%-50% - -

External Beam Radiation Therapy

20%-45% 2%-16% 6%-25% 

Brachytherapy (seeds)

36%2 6%-12%2 18%2

Androgen Deprivation Therapy(LHRH agonists) 

40%-70% Breast Swelling: 5%-25%Hot Flashes: 50%-60%

ANDROGEN DEPRIVATION THERAPY

• Bilateral Orchiectomy

• LHRH agonists (e.g., goserelin or leuprolide (Lupron))

PSA SCREENING AT AGE 70

• 50% Life expectancy = 10 years

• Prostate CA with 90% 10 yr survival rate

• Less QALYs to be gained, higher harm, but also much higher number of cancers detected

ALTERNATIVE TO PSA

• early prostate cancer antigen (EPCA), a subset of PSA that appears only after the development of prostate tumors

• Genetic markers for Prostate CA

PROSTATE CANCER –ASSOCIATED FACTORS

• Red meat

• High fat diet

• High dairy intake

• Fried and charcoal grilled meat

PROSTATE CANCER PREVENTION

• Alpha-linolenic acid (ALA) (flax seed oil) (50% lower amongst lowest quintile vs top)

• EPA (Fish oil) – 11% less in top quintile (Leitzman Journal of Nutrition, 7/04)

• Selenium 0.12-0.19 ppm vs 0.06-0.09 ppm 50-70% less advanced DZ (Li, Journal of the NCI 5/04)

PROSTATE CANCER PREVENTION – protective

factors• Soy (Gronberg, Lancet, 3/03)

• Tomato (lycopene) (Chen, Journal of the NCI 12/01)

• Vitamin E (Gronberg, Lancet, 3/03)

• Selenium (Brooks, Journal of Urology, 12/01)

• Sun Exposure (Luscombe, Lancet, 8/01)

• Vegetable intake (>28/wk vs <14/wk- 35% less dz) (Cohen, Journal of the NCI, 1/00)

PROSTATE CANCER PREVENTION- NO EFFECT

• Smoking

• Alcohol

• Exercise

• Vasectomy

• Sexual activity

Testosterone exposure?

• Marketing of testosterone for slowing aging in men is beginning, analogous to use of estrogen replacement (HRT) in women in the 1980s

• Effects of disease unknown