Treatment Option for Prostate Cancer
by William J. Catalona, M.D.
Intermittent Hormonal Therapy
is a new, experimental treatment option for prostate
Use of Hormonal Therapy
therapy is usually effective in the treatment of
prostate cancer, especially for patients who have had
recurrence of their cancer after surgery or radiation
The principle of hormonal
therapy is that the male hormone, testosterone,
stimulates prostate cancer cells to grow and spread.
If the testosterone concentration in the blood is
reduced to low levels, most prostate cancer cells will
die or go into a dormant state for an indefinite (though
unpredictable) period of time.
In the past, hormonal therapy
for prostate cancer involved the continuous
administration of female hormones by mouth or by having
the testicles removed.
Recently, new medications are
available to achieve the same results with fewer risks,
and their effects are reversible when they are
The side effects of hormonal
therapy can include reduced sexual desire and sexual
function, “warm waves” (similar to “hot flashes”
experienced by women during menopause), dry skin, and
slowing of the growth of facial hair.
With prolonged hormonal
therapy, there can be loss of muscle mass (unless a
vigorous exercise program is followed), loss of bone
density (osteoporosis), anemia, and loss of energy.
Some forms of hormonal therapy can cause breast
enlargement, gastrointestinal upset, blood clots, fluid
retention, shortness of breath, and increased risk for
Use of Intermittent Hormonal Therapy
studies have shown that hormonal therapy may be give
intermittently, thus providing the patient with a
“vacation” from its side effects.
A commonly used program for
intermittent hormonal therapy involves taking to
different types of medication: (1) a pill for 10 days
and (2) injections of
another kind of medication three months apart.
A testosterone “flare”
response occurs during the first 10 days after the
injection (Lupron or Zoladex).
That testosterone “flare” in the first 10
days could cause the tumor to grow.
The 10-day course of an oral
medication (such as Casodex or Eulexin) along with the
scheduled injection blocks the testosterone “flare”
response that occurs during the first 10 days after the
10-day course of oral medication to accompany injection
is an essential component of the intermittent hormonal
way this therapy works is as follows.
A man previously treated with radiation therapy
develops a rising PSA level that reaches 4 on December
rising PSA is an indication that the cancer has
On January 1, he would begin to
take a 10-day course of Casodex pills. On January 2, he would be given a Lupron injection that would
stay in his system for three months.
On April 1, he would check his
PSA level (which would probably be very low) and then
receive his second 3-month Lupron injection.
On July 1, he would check his
PSA level again. If
it is still low, he would stop the hormonal therapy and
monitor his blood PSA level until it reaches a level 4
again, which may take six months to a year or more.
During this time, he would
recover from the side effects of hormonal therapy. When the PSA level is once again 4, he would begin another
Although intermittent hormonal
therapy is experimental, preliminary clinical studies
suggest that the results appear to be equivalent to
those of continuous hormonal therapy.