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The Tables that Revolutionized Treatment Decision-Making: Now Bigger
and Even Better
They call them the Partin tables, and they're everywhere: On several
Internet websites, on laminated cards carried by doctors throughout
the country, even on home computer programs.
Elegantly simple and meticulously accurate, the tables, developed
by urologists Alan W. Partin, M.D., Ph.D., and Patrick C. Walsh, M.D.,
have quietly revolutionized the way doctors and patients are making
decisions about treatment for prostate cancer.
Until these tables, there was no way to predict what urologists might
find when they opened up a patients during radical prostatectomy;
surgery can only cure prostate cancer if the disease has not spread
too far beyond the confines of the prostate. Doctors could guess,
but they couldn't be sure -- not until they examined the patient's
pelvic lymph nodes (in a procedure called pelvic lymph node
dissection), and sometimes not even then, if there were microscopic
bits of cancer that had strayed from the prostate but weren't yet big
enough to be seen.
Ingeniously correlating the three things that were known about
a man's disease -- PSA level, Gleason score, and estimated clinical
stage -- the tables produced something that had been desperately needed:
An accurate, invaluable means of estimating the exact extent of a man's
prostate cancer before surgery.
"We know that if you operated on everybody who came in with these three
pieces of information, at best -- at very best -- about 45 to 50
percent would have organ-confined cancer," says Partin. Because
surgery is best at curing cancers that are truly localized to the prostate,
it would be better for everyone to know before the operation
how extensive the cancer is; this might spare someone unnecessary
surgery.
Similarly, radiation won't cure a man who has cancer in his pelvic lymph
nodes, and the tables can help spare someone needless side effects of
a treatment that won't be helpful.
The tables, first developed after Partin studied the course of prostate
cancer in hundreds of Walsh's radical prostatectomy patients, were designed
to help men and their doctors predict the definitive pathological stage
(determined after surgery, when a pathologist examines the removed prostate
for the presence of cancer) and best course of treatment.
Now the tables have been expanded to include data from three institutions --
The University of Michigan and Baylor College of Medicine, as well as
Johns Hopkins -- and 4,135 men, operated on by nearly a dozen surgeons.
(All three of these institutions have received SPORE grants, for Special
Projects of Research Excellence, from the National Cancer Institute --
see related article.)
This latest study, says Partin, "sharpened the tables by having more
power, because of the higher numbers. It also provided the capability
of testing our hypothesis: We took two-thirds of the patients and
recalculated the tables, and then with the third that we had randomly
chosen, we tested to see how well we did. We were able to calculate
the statistical accuracy of the tables and report that, as well."
(Another advantage of tripling the size of patients in the study is
that it filled in many of the blanks that had been left on the earlier
tables because of a lack of information.)
The four tables predict a man's likelihood of having organ-confined
disease; capsular penetration (cancer that has reached the prostate wall);
cancer in the seminal vesicles; and cancer in the lymph nodes. For example,
a man with a PSA of 3.7, clinical stage T1b, and Gleason score of 6 has a
61-percent chance of having organ-confined disease, with a 23-percent chance
of having positive seminal vesicles.
"I think it's really helped the patients and their doctors when they're
talking to each other about treatment," says Partin, "so the patient
can just say, 'Just what are we looking at, with the information I have
right now?'"
Further Reading
"Combination of PSA, Clinical Stage and Gleason Score to Predict
Pathological Stage in Localized Prostate Cancer: A Multi-Institutional
Update," Journal of the American Medical Association, April
1997. Alan W. Partin, Patrick C. Walsh, et al.
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