Radiotherapy Improves Cure Rate in High-Risk Prostate
by William J. Catalona, M.D.
radiotherapy improves the chances for cancer-free
survival in prostatectomy patients whose pathology
report shows adverse findings.
of adverse findings are the extension of cancer cells
through the capsule of the prostate, to the surgical
margins of resection, or into the seminal vesicles.
margins of resection are the very outer edges of the
surgical specimen, the interface between the tissue that
was removed and that left behind.
vesicles are attached to the prostate like Mickey Mouse
store the semen. They are removed along with the
are a frequent area of early local spread of prostate
value of postoperative radiotherapy has been
controversial, but my recent studies published in CA-A
Cancer Journal for Clinicians and recent studies by Dr.
Richard Valicenti reported in the International Journal
of Radiation Oncology, Biology, & Physics provide
evidence of its effectiveness.
radiotherapy (adjuvant radiotherapy) is controversial
because not all patients with adverse pathological
findings will have tumor recurrence.
In fact, only about 20% to 30% of patients with
tumor extension beyond the prostate or other measurable
surgical margins associated with low or moderate Gleason
grade tumors subsequently will have rising PSA levels. Therefore, many of these patients opt to be followed while
monitoring their PSA levels.
rates are higher (50% to 85%) in men with high-grade
tumors, seminal vesicle invasion, or lymph node
higher-risk patients are also more likely to develop
metastases in other places, rather than local recurrence
in the "bed" of the prostate.
theoretical advantage of radiotherapy three to six
months after surgery is that it is more likely to be
successful when the tumor is smaller, before the PSA
begins to rise. The downside is that it may be over-treatment with
unnecessary side effects for patients who will never
have tumor recurrence, and it may be inadequate
treatment for those whose tumor has already spread to
sites away from the prostate.
patient has to be involved in the choice of whether or
not he wants the postoperative radiotherapy.
It usually hinges on how much he fears the
potential side effects of radiotherapy.
The risks of radiation therapy after prostate
cancer surgery include a 3% to 4% rate of permanent
injury to the rectum (causing rectal bleeding, diarrhea,
and rectal urgency) or the bladder (causing bladder
bleeding, urinary urgency, and a small capacity bladder)
and a 50% risk of damage to the neurovascular bundles
resulting in delayed impotency.
from a cancer control standpoint, it's always safest to
go ahead with the radiation in patients whose pathology
report after a radical prostatectomy shows adverse
findings. Increasing evidence suggests that giving radiotherapy before
the PSA level rises about 1 is preferable.
results show a 10% to 20% higher likelihood of
maintaining an undetectable PSA level in patients with
all types of adverse pathologic finds and all Gleason
my series, in patients who elected to delay receiving
radiotherapy until their PSA level rose, 68% had an
undetectable PSA following radiotherapy.
Of patients whose PSA level was still detectable
after surgery or who had rising levels within six months
of surgery, 33% had undetectable PSA levels after
the first group, the PSA levels became undetectable
after surgery and only after a long time did they begin
to creep up. This
group is a relatively favorable one for radiation
the second group, the levels either did not become
undetectable after surgery or they began to rise very
soon after surgery.
This group is a less favorable one that is more
likely to have distant metastases.
Valicenti and associates recently reported that at four
years after surgery, 88% of the patients who had the
radiotherapy also had undetectable PSA levels, compared
to 55% of the patients who did not have the auxiliary
Valicenti's studies also suggest that a higher radiation
dose (64.8 Gy) produces better results than lower