Leonard S. Marks, M.D.
Medical Director, USRF
1st Quarter, 2000 - Baltimore, MD (February 22, 2000)---A
"Best Practice Policy" for use of PSA testing was issued by the American
Urological Association (AUA) today. The policy, which was developed
by a multidisciplinary panel of 8 and peer reviewed by 47 experts from
urology, internal medicine, gerontology, oncology, and radiation
therapy, appears to establish major guidelines for the foreseeable future.
The entire policy was published in the February issue of Oncology and
is publicly available online free at http://www.cancernetwork.com.
Measuring blood levels of PSA (prostate specific antigen) is now the
commonest means of detecting prostate cancer. The diagnosis must be
subsequently established by biopsy, since the PSA test is not specific
for cancer. According to Ian Thompson, M.D., the chairman of the panel
of experts, the new policy report distills available data about PSA
"…down to a short, easy to digest balanced document on what we know
about the subject relating to the diagnosis, staging, and management
of prostate cancer." Of all prostate cancers currently detected, approximately
75% are associated with an abnormal PSA test.
Regarding early detection of prostate cancer, the expert panel concluded
that routine PSA testing shoudl be offered in men when:
Age is 50 years and greater, unless the man has increased risk factors,
such as genetic predisposition via family history or African-American
racial status. In these "at risk" men, PSA testing should be offered
between 40 - 50 years of age.
- AND life expectancy is at least 10 years.
- AND should be performed in conjunction with the digital rectal exam
(DRE), since the combination of the two tests is more sensitive for
diagnosis than either one alone.
Regarding prostate biopsy, the panel concluded that this is indicated
- PSA is 4.0 ng/ml or greater.
- PSA has increased substantially from one test to the next. An increase
of 0.75 ng/ml or more between two annual tests appears to be reason
- DRE is abnormal. Since approximately 25% of prostate cancers are
associated with PSA levels below 4.0 ng/ml, the DRE is also very important.
Regarding use of PSA testing in the staging of men with known prostate
cancer, the experts concluded:
- Men with PSA levels below 10 ng/ml are most likely to have localized
disease and respond well to local therapy (radical prostatectomy or
- Routine bone scans are generally not required for men with clinically
localized prostate cancer when their PSA is < 20 ng/mL.
- CAT scans and MRI scans are generally not indicated if the PSA level
is less than 25 ng/ml.
- Pelvic lymph node dissection is probably not necessary if PSA level
is less than 10 ng/ml or if PSA is less than 20 ng/ml AND the Gleason
score is < 6.
Regarding use of PSA testing in the follow-up of men after treatment
for prostate cancer, the panel members determined the following:
- Periodic PSA testing should follow any form of treatment for prostate
cancer, since PSA levels can indicate need for further treatment.
- Following curative radical prostatectomy, PSA levels should become
- Following curative radiation therapy, PSA levels should fall to
very low levels, probably < 0.5 ng/ml, and should not rise on any
successive tests. The nadir value is not reached for a median of 17
- The pattern of PSA rise after local therapy for prostate cancer
can help distinguish between local recurrence and distant spread.
Biochemical recurrence (PSA) occurring > 24 months after local treatment
and who have a PSA doubling time >12 months are likely to have local
recurrence. Others are like likely to have distant spread.
- Following androgen deprivation therapy, men who experience a PSA
decrease of more than 90% from baseline (or undetectable levels) at
3 and 6 months are likely to have a prolonged progression-free survival.
- Following secondary treatment in men with hormone-refractory prostate
cancer, a decrease in PSA levels of 50% or more after 8 weeks indicates
improved survival in response to the new treatment.
|Based on an AUA news release and the "Best Practice Policy" published
in the February, 2000 issue of Oncology.
The PSA test was first brought to market in 1986 by Hybritech, Inc.,
which is now a division of Beckman
Coulter, Inc. Additional sources of PSA information are available
online at the following websites:
of Free PSA Testing
Selected USRF publications relating to PSA:
American Cancer Society
on early detection of prostate cancer.
AUA Patient Education brochure:
Cancer Awareness for Men.