Early Test for Cancer of Prostate Is Unveiled
By THE ASSOCIATED PRESS
ATLANTA -- It is not exactly the male Pap test, but checking for an
abnormal growth called PIN may give men who fear prostate cancer the same
early warning that women receive for cervical cancer. In a presentation
here on Sunday, doctors said that checking the prostate gland for PIN,
short for prostatic intraepithelial neoplasia, could often catch cancer in
the making.
The Pap test, developed in the 1940's, offers a way of spotting the
earliest stage of cervical cancer while it is still easily treated with
surgery. There is no male equivalent for diagnosing prostate cancer, the
leading cancer among men. But doctors say looking for PIN appears to offer
some of the same advantages. The goal is to find cells in the prostate
gland that are on the verge of becoming cancerous. Doctors have suspected
since the 1980's that prostatic intraepithelial neoplasia may be cancer's
earliest stage, but a new study shows that it truly is an ominous sign.
Doctors in Boston treating military veterans found that those with the most
abnormal, or high-grade, stage of the growths had double the usual risk of
developing outright prostate cancer.
The discovery confirms the growing belief that doctors should take the
growths seriously. But they are still unsure what, if anything, they should
do differently when they discover it. There is no good evidence that
removing these men's prostate glands will ward off death from cancer,
although this is possible. "High-grade PIN definitely predicts for a high
risk of prostate cancer," said Dr. Christopher Nauman of Boston University
School of Medicine. "We have to watch them very closely."
Dr. Nauman presented the findings at a meeting of the American Society of
Clinical Oncology. Checking for prostatic intraepithelial neoplasia is
far more difficult than checking for cervical cancer. The Pap test involves
a quick and simple swab of the surface of the cervix to sample cells.
Looking for the prostate growths involves a much more difficult and costly
biopsy using a needle to draw out cells for examination.
In his study, Dr. Nauman reviewed the cases of men who underwent prostate
biopsies between 1989 and 1993 because blood tests suggested possible
cancer or doctors felt lumps in their prostates.
Sixty-one of the men had high-grade PIN, while 47 did not. After seven
years of follow-up, prostate cancer was found in 49 percent with high-grade
PIN, compared with 21 percent of the other men.
There were too few cancer deaths in either group to show if knowing the
men's PIN status improved their chances of survival.
Because the men were relatively old -- their average age was 69 -- doctors
did nothing beyond watching them closely. Doctors are often reluctant to
operate on older prostate patients, because they may die of something else
before slow-growing prostate tumors cause serious problems.
Nevertheless, prostate cancer is the leading malignancy of men, trailing
only lung cancer in mortality. Because of routine PSA testing, doctors
are increasingly finding prostate cancer in men in their 50's. At that age,
more aggressive treatment may be worthwhile to catch the cancer before it
escapes the prostate gland.
"This study is important, because if you find PIN in a young man, you have
to be very suspicious that he will soon have cancer," said Dr. Deborah
Kuban of Eastern Virginia Medical School in Norfolk. Doctors now
recommend that men with high-grade PIN undergo biopsies every three to six
months.
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Copyright 1999 The New York Times Company