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Inappropriate Drug Prescribed For Prostate Cancer Doctors
frequently prescribe an inappropriate drug to men with early prostate
cancer. Though the consequences of this treatment are severe, most men
reported a high degree of satisfaction with their care. These paradoxical
findings come from the first major study to look at the quality of life for
men who were not treated surgically or with radiation therapy.
This study is an important contribution to the debate about whether the
prostate-specific antigen (PSA) screening test for prostate cancer causes
more harm than good. As its use increased dramatically over the last decade,
so too has the diagnosis of early prostate cancer. The blood test is now
routinely given to men with no symptoms, though studies show that most
prostate cancers remain dormant an entire lifetime. Consequently, many men
are treated unnecessarily. Previous studies of men with early disease who
remained untreated showed that their prostate cancer death rate was similar
to that of men given a prostatectomy. Neither the PSA test, nor any other,
can accurately identify the minority of prostate cancers destined to be
fatal. And there is no proof that treating the potentially fatal version at
an early-stage saves lives.
There is a consensus among researchers, though not among urologists, that
the decision to remain untreated is a valid choice. This used to mean-no
treatment until symptoms occur ("watchful waiting"). But now it appears that
many men who forego a radical prostatectomy or radiation therapy are being
treated with a drug that stops their production of the male hormone,
androgen. Known as androgen deprivation therapy (ADT), the treatment amounts
to a medical castration, usually with the injectable drug, Lupron.
Lupron has been tested and proven useful only as a palliative treatment for
men with advanced prostate cancer. A palliative treatment means that the
drug can only alleviate symptoms. And now the drug is being prescribed for
early-stage cancer in men without symptoms-at a great physical cost,
according to the new study published recently in the Journal of the National
Cancer Institute (3/20/02). "There is no definitive evidence that early ADT
alone improves length or quality of life in men with clinically localized
prostate cancer," according to the study's authors, Arnold L. Potosky, PhD,
and colleagues.
All of the men who agreed to take part in this study had been newly
diagnosed in 1994-5 with cancer that had not spread beyond the prostate
gland. They are participants in a much larger project called the Prostate
Cancer Outcomes Study (PCOS), initiated by the National Cancer Institute to
investigate variations in the treatment of prostate cancer and to determine
how the men fared afterward. Significantly, the PCOS is primarily following
men who were treated at community medical practices, as opposed to a
research-based cancer center. The participants include men under 60, as well
as African-Americans and Hispanics, represented in higher proportions than
white men over the age of 60.
Out of the PCOS database of over 3,000 men, Dr. Potosky and colleagues
concentrated on the 661 who had not been treated with surgery, radiation, or
cryotherapy (destruction of the gland by freezing it) and were followed for
at least one year. They found that an astonishingly high proportion-37%-had
been given ADT alone as their primary treatment, which was described as "an
indication authoritatively endorsed nowhere in the medical literature," by
James A. Talcott, MD, in an editorial that accompanied the new study.
Compared with men who were just observed-that is, given no treatment, the
ADT-treated men were five times more like to have breast swelling and hot
flashes. Those who were sexually potent prior to ADT were more than twice as
likely to be impotent afterward. The overall physical functioning and
vitality tended to be poorer among the men given ADT.
Though no scientific evidence supports the use of ADT for preventing or
delaying onset of symptoms, Potosky and colleagues were able to identify a
rationale for the doctors' prescription by going through the men's medical
records. The ADT-treated men were more likely to have palpable tumors, more
poorly differentiated tumors and a baseline PSA values over 10 ng/dL. In
other words, their condition at diagnosis was viewed as worse than men with
non-palpable, well differentiated tumors and a PSA under 10 ng/dL. The
characteristics of the ADT-treated men indicate that their cancers could
have spread outside the prostate.
Though it seems logical to treat the men whose cancer might be slightly more
advanced, it is illogical to prescribe a drug that can only relieve symptoms
in men who have none. Surprisingly, despite the distressing side effects,
more ADT-treated men (56%) reported that they were "pleased" or "delighted"
with their treatment (56%) than men who decided to remain untreated (45%).
Additionally, the ADT-treated men believed themselves to be free of cancer
at a 12% higher rate.
This study indicates that-for many men-the need for treatment may be more
important than whether it actually works. The 661 participants came from a
far larger pool of men with early-state disease participating in the
Prostate Cancer Outcomes Study. The overwhelming majority of the PCOS
participants have been treated with either surgery or radiation for
early-stage prostate cancer. They face a dilemma with no scientific evidence
to guide them because there has been no head-to-head comparison of the
different options. Most men become permanently impotent no matter which
treatment is chosen, and urinary incontinence or bowel symptoms are common
depending upon the choice of treatment.
The new ADT study and the PCOS provide information that all men should
consider before they consent to a PSA screening test. This test was
prematurely introduced into medical practice before it could be determined
whether it saves lives or whether its benefit outweighs the considerable
harm of being unnecessarily treated. Significantly, most organizations that
promulgate screening guidelines do not recommend the PSA test for
symptomless men. Even the American Cancer Society withdrew its
recommendation and now says that men should be offered the test and be
informed of the benefit and risks.
But many physicians appear to be convinced of the test's merit as it has
become commonplace in medical practice. In fact, it is often included within
the blood testing for other purposes, such as cholesterol, without the
patient's knowledge. A survey of internists and family physicians found that
the frequency with which doctors ordered PSA tests rose from 73% of the time
in 1993 to 81% of the time in 1998.
John D. Voss, MD, and colleagues, who published the survey results at the
end of last year in the Journal of General Internal Medicine, concluded that
the decision to test is not always driven by concerns related to a patient's
health. They believe that the pressure on doctors to screen for prostate
cancer is in response to a decade of lobbying for the test by the American
Cancer Society and the American Urological Association.
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