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Practical Urology: EssEntial PrinciPlEs and PracticE

of factors including environment, genetics, diet/

The results of ongoing trials will hopefully clar-

lifestyle factors, and access to care.

ify this unexpected finding.

Dietary factors have also been examined for

Risk Factors and Prevention

prostate cancer prevention. Based on observa-

tional studies, both selenium and vitamin E were

thought to potentially have a role in prostate

Family History

cancer prevention. However, results of a recent

randomized controlled trial demonstrated that

Family history is a consistent risk factor for

neither selenium nor vitamin E, alone or in com-

bination, decreased the incidence of prostate

prostate cancer. Men with a single first-degree

cancer as compared to placebo.9

male relative (father or brother) have twice the

risk of prostate cancer as men without this fam-

ily history. The risk of prostate cancer increases

Screening and Diagnosis

with an increasing family history of disease.5,6

Based on this familial association, several stud-

Current Screening Recommendations

ies have investigated genes, particularly single

nucleotide polymorphisms (SNPs) that may be

Early detection of prostate cancer through

associated with increased prostate cancer risk.

These studies have noted associations with SNPs

annual PSA testing with digital rectal examina-

located in three regions of 8q24, and one region

tion is a subject of active debate in the medical

on 17q12 and 17q24.3, among others, and exam-

literature. The American Urological Association

ined the potential for using these SNPs as screen-

recommends that average-risk men 50 years of

ing markers for prostate cancer.7

age or older with at least a 10 year life expectancy

be offered PSA testing (with digital rectal exam)

Diet and Lifestyle

annually for the early detection of prostate can-

cer.For men at higher risk (i.e.,African-American

A number of dietary and lifestyle-associated

race or family history), PSA testing may be

offered at a younger age. Similarly, the American

risk factors for prostate cancer have been pro-

Cancer Society suggests that men aged at least

posed, including dietary fat, smoking, alcohol

50 years with a 10 year life expectancy be offered

consumption, and obesity. Unfortunately, epide-

PSA testing with DRE to detect prostate cancer.

miologic studies examining the association

Again, men with additional risk factors should

between these factors and prostate cancer inci-

be offered PSA testing at a younger age. With

dence have yielded mixed results. Therefore,

both groups, the emphasis is on a discussion of

definitive evidence linking these diet and life-

the potential risks and benefits between the

style influences to the development of prostate

patient and his physician, recognizing the limita-

cancer is lacking.

tions of sensitivity and specificity of PSA testing

for prostate cancer,10,11 overdetection of clini-

Prevention

cally insignificant disease,12,13 and the uncertain

benefit of early detection and treatment of pros-

Prostate cancer is an attractive target for chemo-

tate cancer.14–16 The National Comprehensive

prevention efforts because of the dependence of

Cancer Network has recently advocated a risk-

prostate cancer development on androgens.

stratification approach to PSA testing, wherein

Results from the Prostate Cancer Prevention

men with a PSA ³0.6 ng/mL at 40 years of age are

Trial demonstrated a 24.8% relative reduction in

recommended to undergo PSA testing annu-

the risk of prostate cancer among men random-

ally.17 Early results of two randomized trials of

ized to daily finasteride as compared to placebo.8

prostate cancer screening demonstrate only a

However, a reported increase in high-grade

small mortality reduction, if any, to prostate can-

cancer detection in the finasteride group has

cer screening.18,19 However, the results of the U.S.

hindered adoption of finasteride for this pur-

study are potentially limited by a high rate (up to

pose. Recent PCPT follow-up studies suggest

52%) of PSA testing in the “non-screening”

that the observation of high-grade cancers in the

arm.18 Proponents of early detection for prostate

finasteride group may be a detection artifact.

cancer point out the significant stage migration