Oottamasathien and Crawford
advance a hypothesis with
which I heartily agree-androgen
deprivation/antagonist (AD/A)
strategies should be considered in many
more patients than urologists and oncologists
traditionally teach. However,
I think the authors could substantially
sharpen their message. I would like to
make five specific points, and then
offer a few nitpicking comments.
Redefine Advanced Disease?
The authors suggest that we need
to redefine what we consider to be
advanced disease. I disagree with this
suggestion. Redefining "advanced"
disease may be emotionally and subjectively
counterproductive-do we
really want to tell our patients that
their disease is worse? I think not.
We desperately need to apply the
risk assessment tools currently available
and recognize that the risk of prostate-
specific antigen failure equals
neither the risk of detectable metastatic
disease nor the risk of prostate mortality.
We must use these tools to define
patients in whom randomized, adequately
powered studies of AD/A are
conducted. Then we must convey the
concept of risk and the areas in which
we lack knowledge to our patients.
It is instructive to remember that
our colleagues who care for women
with breast cancer did this 40 years
ago-systemic adjunctive studies
of estrogen deprivation/antagonists
(ED/A) as well as cytotoxic agents were
begun in the late 1960s in women
with breast cancer. Risk assessment to
judge entry in these studies employed
nodal status, tumor size, menopausal
status, and, more recently, biochemical
characteristics (estrogen and progesterone(Drug information on progesterone)
receptors, HER2/neu). Tens
of thousands of women have entered
studies comparing ED/A strategies vs
placebo, cytotoxic therapy with or without
ED/A, and biologic agents (trastuzumab
[Herceptin]) and alternative
forms of ED/A. What have we done in
terms of comparable studies in men
with prostate cancer? Very little.
Message of the VA Cooperative
Group Studies
In my view, the Veterans Affairs
(VA) Cooperative Group studies, conducted
in patients staged only with
plain radiographs, acid phosphatase,
and physical exam, and in which
crossover to AD/A was unregulated
or monitored, represent the first-and
perhaps the best-trials we have done
in prostate cancer. They are the best
because they entered large numbers
of men in a randomized setting with
state-of-the-art trial designs. Given
methodologic improvements that have
occurred over the past 40 years, the
failure of the VA Cooperative Urological
Research Group (VACURG)
studies to prove a long-term survival
advantage with AD/A strategies
should not be assumed to mean that
these approaches are of no use.
Best Approach to AD/A
From the Patient's Perspective
The authors present a logical inconsistency
in our current approach.
Cassileth et al (Oottamasathien and
Crawford's reference 13) suggest that
men prefer luteinizing hormone-
releasing hormone (LHRH) analogs
to orchiectomy (in a study funded by
an LHRH analog manufacturer), but
Potosky et al (their reference 14) report
more sexual dysfunction with
LHRH analogs than orchiectomy. This
issue should be reassessed, and we
should recognize that:
- No substantiated data have yet proven the superiority of intermittent vs continuous AD/A. Therefore, the merit of the reversability of LHRH analog-induced castration is uncertain.
- It takes a considerable amount of time to really discuss surgical castration compared to LHRH analogs.
- There are incentives other than our patient's psychological and sexual well-being that have an impact on the choice of AD/A strategies.
I think not. That design would address a different issue than the one at hand. The studies of the European Organization for Research and Treatment of Cancer (EORTC) and Radiation Therapy Oncology Group (RTOG) asked a straightforward and carefully framed question-does adjunctive AD/A improve outcome in high-risk localized prostate cancer? The answer is an unqualified yes. At the recent American Society of Clinical Oncology meeting, Pilepich reported the more mature results of RTOG 85-31.[1] Survival and prostate cancer-specific survival were superior for irradiation (P < .001) with LHRH analog compared to irradiation only. In certain high-risk groups, AD/A improves survival obtained with irradiation. The role of AD/A alone and more precise definition of the risk subgroups who benefit will require other studies. But to this reviewer's eye, the overall answer is clear. Does AD/A Cause Osteoporosis?
The authors assert that "multiple groups argue that men receiving hormonal therapy do not have significantly lower bone mineral densities than age-matched controls" (an assertion supported by a single reference to an abstract). I heartily disagree. To the contrary, there are multiple groups who have reported clear differences in bone mineral density (BMD) in men who have undergone AD/A.[2] The Mayo Clinic group recently reported a substantial increase in fracture risk among castrated men with prostate cancer compared to age-matched controls.[ 3] Intermittent AD/A has been shown to have a lesser impact on BMD than continuous AD/A, and bisphosphonates modulate AD/A-mediated bone loss. AD/A use is clearly associated with an increased risk of osteoporosis, and osteoporosis-at least in women, in whom it has been adequately studied=is associated with increased fracture risk. Hip fractures in elderly patients are associated with a 25% 30-day mortality. We must consider this risk as we decide in whom and for how long to employ adjunctive AD/A. Additional Considerations
Several other points merit attention; the reader is referred to the appropriate literature for a more complete and balanced discussion[4-7]:
- The role of high-dose antiandrogen monotherapy and the blockade of gynecomastia by antiestrogens.
- Why was the outcome of the LHRH analog with or without antiandrogen trial different from that of the orchiectomy with or without antiandrogen trial? Was it the "flare," or was it the fact that the LHRH analog was to be given by the patient daily?
