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National Comprehensive Cancer Network (NCCN) Establishes
2006 Guidelines For Early Detection Of Prostate Cancer.
(October 2006)
In May,
2006, on the recommendation of its panel of prostate cancer experts the
NCCN published a revision of the professional practice guidelines for PSA
screening. The new recommendation is that a biopsy should now be
considered for DRE negative men with PSA >2.6 ng/mL. or
a PSA velocity of >0.5 ng/mL/yr when the PSA is < 2.5 ng/mL. This
information is found on the NCCN.org web site in the prostate cancer
section of "Guidelines for Detection, Prevention, and Risk Reduction" on
screen PROS D5. Reference is made to the addition of %free PSA in the
decision as to whether to perform a biopsy, and they suggest that for
%free PSA < 10 - perform biopsy; for %free PSA 10-25 - consider a
biopsy; and when the free PSA is > 25% - no biopsy. In the footnote
section additional comments include: 1) "For men with PSA < 4 ng/mL, data
suggest that a PSA velocity of >0.5 ng/mL/yr is suspicious for the
presence of cancer, and a biopsy is recommended; 2) "for men with PSA 4-10
ng/mL a PSA velocity of >0.75 ng/mL/yr is suspicious for cancer"; 3)
"Measurement should be made on at least three consecutive specimens drawn
over at least an 18-24 mo. interval"; and lastly, "The same assay should
be used" [and] ... "biologic variability may be a confounding factor in
determining PSA velocity". Other factors affecting the biopsy decision are
"patient's age, co-morbidity, %free PSA, prostate exam/size, strength of
family history, African American".
The lower
PSA threshold of >2.5 ng/mL will certainly lead to more biopsies and an
increased rate of prostate cancer diagnosis, but will not avoid the
stubborn problem of the PSA test's low specificity. The Prostate Cancer
Prevention Trial found that for men with a normal DRE and PSA level
between 2.1 - 3.0 ng/mL the incidence of cancer was ~21%; and was ~24% in
the PSA range of 3.1-4.0 ng/mL. Urologists are well aware that more than
70% of biopsies based only on the PSA value will be negative.
PSA Velocity and age-adjusted PSA ranges each individually
can add useful nuance in PSA interpretation. In his Abstract #1, 2006
Prostate Cancer Symposium, Dr. Judd Moul (recently elected to serve on the
NCCN prostate cancer panel of experts) presented a study combining
the two and created "age-normalized PSA velocity" thresholds to
guide the decision of whom to biopsy. "PSAV was calculated and its
percentiles were normalized to ages 40-59, 60-69, and > 70 as well as PCa
status." Statistical considerations indicated that optimal PCa detection
would result if biopsies were performed if the PSAV exceeded 0.25 ng/mL/yr
in men 40 - 59; 0.05 ng/mL/yr for 60-69; and 0.75 ng/mL/yr in men older
than 70 years. By using these thresholds in evaluating the biopsy outcome
of 11,347 men with PSA values < 4.0 ng/mL the cancer detection rate in the
age group 40-49 years was 35% and was 57% in the 60-69 year old cohort,
compared to the detection rate of 19% and 25% using the "traditional
standard (0.75 ng/mL for all age groups)." Dr. Moul et al. concluded that
the use of these age-normalized PSAV thresholds "could
substantially improve PCa detection".
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