© The Canadian Journal of Urology™; 19(Supplement 1); October 2012
Address correspondence to Dr. Bobby Shayegan, St. Joseph’s
HealthcareHamilton, 3
rd
FloorMaryGraceWing, 50 Charlton
Avenue East, Hamilton, Ontario L8N 4A6 Canada
PSA implications and medical management of
prostate cancer for the primary care physician
Sabeer Rehsia, MD, Bobby Shayegan, MD
Department of Surgery, McMaster University, Hamilton, Ontario, Canada
REHSIA S, SHAYEGAN B. PSA implications and
medical management of prostate cancer for the
primary care physician. Can J Urol 2012;19(Suppl 1):
28-35.
Prostate cancer remains a common cancer diagnosis
and cause of cancer-related death in men. Despite it’s
high prevalence, screening for prostate cancer for early
detection remains controversial. This article outlines
evidence from contemporary prostate cancer screening
clinical trials and presents an overview of therapeutic
options across the spectrum of prostate-cancer states.
Key Words:
prostate adenocarcinoma, prostate
cancer, prostate cancer screening, prostate-specific
antigen (PSA)
it is relatively low. In Canada, the lifetime probability
of being diagnosed with prostate cancer is one in
seven, while the associated risk of death is only one in
27.
1
This discordance between prevalence of prostate
cancer and risk of subsequent death is related to the
relative indolence of many of the screening diagnosed
cases. Astudy of incidental prostate cancer diagnosed
in organ donors found prostate cancer in one in three
men aged 60 to 69 years, but found prostate cancer in
46%
of men over age 70.6 years.
2
PSA
Prostate-specific antigen (PSA) is a 33-kD glycoprotein
that is secreted by prostate epithelial cells and
functions to liquefy semen.
3
Prostate cancer cells do
not produce more PSAthan normal prostate epithelial
cells, but the disruption of epithelial cell architecture
in prostate cancer results in an increased “leak” of
PSA into the bloodstream.
3
Other causes for elevated
PSA include benign prostatic hyperplasia (BPH),
prostatitis, urethral instrumentation, prostate biopsy,
and ejaculation.
1
28
Introduction
Prostate cancer is the third leading cause of cancer-
related mortality in Canada.
1
Despite this high
prevalence, screening for prostate cancer remains
controversial due to conflicting clinical-trial evidence
to support its widespread use. In Canada, primary
care physicians remain at the forefront of discussing
the potential benefits as well as the pitfalls of
prostate cancer screening with men at risk. In this
article, the term “prostate cancer screening” refers
to an assessment of serum prostate-specific antigen
(
PSA) level along with a digital rectal examination
(
DRE).
Epidemiology of prostate cancer
While prostate cancer remains highly prevalent, the
probability that a man with the disease will die from
