DOCTOR'S VIEW ARCHIVE
New Criteria May Help Predict Insignificant
Form of Prostate Cancer
ROCHESTER--A common form of prostate cancer that
is clinically insignificant can be predicted with reliability
using a new set of criteria according to study from the Mayo
Clinic.
Prostate cancer killed over 40,000 Americans in 1995.
Prostate cancer is second only to lung cancer as a male cancer
killer in the United States. While 40% of men in their 40s and
50s have at least tiny areas of undetected cancer in their prostate
glands, prostate cancer accounts for only 3% of US male deaths.
The ability to define clinically insignificant prostate
cancer in a patient with a relatively short life expectancy could
help avoid unnecessary surgery, radiation therapy, or other
treatments,
and, until now has not been possible.
In a study recently published in the Journal of the
American Medical Association, Joseph Oesterling, M.D. and associates
described their data which resulted from a review of 337 prostate
specimens.
The authors concluded that by using a combination
of criteria they were able to define an individual prostate cancer
as clinically insignificant. These criteria included cancer volume,
grade, cancer volume doubling time, and the life expectancy of
the patient.
These criteria basically allowed the authors of the
study to define relatively slow-growing cancers in aging men.
The authors point out that "prostate cancer is clinically
insignificant until it causes bladder outlet obstruction, local
invasion, mass effect, or symptomatic metastases."
In order to become "clinically significant"
the cancer must grow to a certain size. The authors of the study
emphasize that technologic advances will permit more accurate
measurements, and therefore, predictability in the future. They
further note that the prostate specific antigen (PSA) test doubling
time can also provide useful information about the current cancer
growth rate.
Later studies may refine these criteria, but they
are certainly an encouraging approach to the evaluation of patients
with this common and often silent cancer.
Readers are referred to the Prostate Cancer site
of the Diseases and Treatments section
for more information on prostate cancer.
Last Editorial Review: 12/31/1997