“Nerve-sparing” Surgery
Turns 20
FLASHBACK:
The bad old
days, the late 1970s. Doctors who treated prostate cancer had
few weapons in their arsenal. One was radical prostatectomy, developed
by Johns Hopkins urologist Hugh Hampton Young in 1904; another
was the retropubic approach, first described in the 1940s.
Both procedures were known to cure cancer,
if it was still contained within the prostate, but at a terrible
price. Every man was impotent after surgery, and 25 percent had
severe problems with urinary control. Worse, the retropubic procedure
itself was life-threatening, because of the horrendous bleeding
that went along with it.
Another option
was external-beam radiation treatment, introduced in the 1960s.
Radiation did not cure prostate cancer as well as surgery, but
at least it had fewer side effects—and to many men, this
presented a more attractive alternative. Hormonal therapy, a stopgap
measure, was also bleak—castration, which immediately shut
off the production of testosterone, and temporarily slowed the
growth of cancer.
Urologist-in-chief
Patrick C. Walsh, M.D., began devising the procedure that would
later bear his name with the simple goal of finding surgical methods
to lessen the bleeding—“so we could actually see what we were
doing, instead of blindly feeling our way,” he recalls. “Like
many urologic surgeons, I was appalled by the blood loss in these
men.”
Walsh spent
years studying the anatomy of the blood vessels (particularly,
the large veins) surrounding the prostate, and developed new techniques,
which did two things: First, with the bleeding under control,
the operation became much safer. And with the now “bloodless field,”
for the first time, critical structures—which previously had been
unrecognized and damaged, simply because they were swimming in
blood and invisible—could be looked for and saved. More precise
dissection and reconstruction reduced the likelihood of significant
urinary incontinence to 2 percent, and of those 2 percent, incontinence
is generally mild.
Breakthrough
In Understanding How Potency Works
But
what about impotence? “Everybody believed that penile nerves were
automatically damaged by the radical prostatectomy,” says Walsh.
The assumption was that the nerves that controlled erection ran
through the prostate, and were destroyed when the prostate was
removed. This was considered an unavoidable hazard, the price
of curing cancer.
“Even the textbooks
said that this was the case,” Walsh says. “One highly respected
anatomy textbook stated merely that the nerves that enable erection
were ‘extremely small, difficult to follow in the adult cadaver,’
and that their location was known ‘merely through experimental
studies.’ But it didn’t make sense to me that the nerves from
one organ would run through another organ.”
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“If
we could just figure out where these nerves were— and then
find a way to save them but still cure prostate cancer—then
men would no longer be faced with an either-or situation.
They could be cured of cancer, and remain potent.”
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Around
this time, “something unbelievable” happened to Walsh. “In 1977,
one of my patients returned for a follow-up visit three months after
surgery and reported that he was potent. To me, this news was staggering—how
could this man be potent, if the nerves that control potency were
inside the prostate that I had removed? Furthermore, if this could
happen to one man, then why only
this one? Why weren’t all men potent after radical prostatectomy?
The key was finding these elusive nerves. If we could just figure
out where they were—and then find a way to save them but still cure
prostate cancer— then men would no longer be faced with an either-or
situation. They could be cured of cancer, and
remain potent.”
In
1981, Walsh went to the Netherlands for a conference, and met Pieter
Donker, a urology professor, recently retired, who was studying
anatomy and tackling unanswered questions. “No one had successfully
dissected the nerves to the bladder, because they were difficult
to identify in adults” says Walsh. “However, these nerves are not
nearly so obscured in infants.” At
the laboratory where Donker was working to trace these nerves in
the cadaver of a stillborn male infant, Walsh asked the Dutch urologist
if he knew what happened to the other end of this plexus of nerves—“the
ones that controlled penile erection. ‘I’ve never looked,’ he said.
We got to work. Four hours later, we were jubilant. We could see
clearly that the nerves were outside
the capsule of the prostate—and that, indeed, it was possible to
completely remove the prostate and preserve sexual function!”
The next step was to apply
what Walsh and Donker had found in infant cadavers (where nerves
are easier to see for many reasons, including the fact that infants
have less fatty fibrous tissue than adults), and locate these tiny
structures in the deep, complicated recesses of the pelvis in adult
men. Over the next months, Walsh made another important discovery:
He noticed a jumble of arteries and veins that traveled along the
edge of the prostate in the exact location where these nerves were
found in the infant cadaver. Perhaps, he thought, these blood vessels
acted as they do elsewhere in the body—maybe they provided a scaffolding
for these microscopic nerves. And maybe he could use the bundles—instead
of pinpointing the microscopic nerves themselves—as landmarks. Donker
agreed. Walsh tested this theory while performing an operation called
a radical cystectomy, removal of the prostate and bladder, in a
67-year-old man. “I had never seen or heard of a patient who had
been potent after this operation. But 10 days after surgery, this
man stated that he awoke in the morning with a normal erection.”
A month later, on April 26,
1982, Walsh performed the first purposeful nerve-sparing radical
prostatectomy, on a 52-year-old professor of psychology. This man
regained his sexual function within a year, and has remained complication-free
—and cancer-free—ever since. Over the years, Walsh has made many
modifications in his original operation. “Now that we’ve learned
exactly where the scalpel can and cannot go, depending on the extent
of a man’s cancer, it has become possible either to save these nerves
deliberately, or to remove more tissue by cutting these bundles
away than we previously had believed possible.” It used to be that
surgeons never excised these nerves, because they were adherent
to the rectum; instead, surgeons just cut the nerves and unknowingly
left them in place.
With these anatomical techniques,
“we now have a better chance of removing all the cancer,” says Walsh.
“Many people call this a nerve-sparing operation, but a more accurate
description is that it’s an anatomic radical prostatectomy, because
there are actually two things going on. One is preserving the nerves;
the other is creating wider margins, by excising them when necessary,
removing as much tissue as possible around the cancer, and making
this a better cancer operation.”
| Impotence
was considered an unavoidable hazard, the price of curing
cancer. |
Of Walsh’s patients, 86 percent of men under age
65 who undergo radical prostatectomy are potent, only 2 percent
wear a pad that they change more than once a day, and the cancer
control rates are used as the “gold standard,” to which all other
forms of treatment are compared. For more on this operation’s significance
in prostate cancer treatment, see “From
the Director”
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