Just a heads up......Dr. Gerard Morton is the one who did Ron's HDR
radiation treatment.

I believe someone asked very recently about being able to pinpoint a shift
in the prostate gland.

Heather
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TORONTO (CP) - In what's being hailed as a world's first, a Canadian-made
device is allowing doctors to target radiation therapy for prostate cancer
with pinpoint accuracy, thereby avoiding damage to surrounding organs and
ensuring all malignant cells are destroyed.

The device, which marries CT and 3D-ultrasound imaging technology, allows
radiation beams to be directed only at the walnut-sized male sex gland,
which can move position slightly from day to day, said Dr. Gerard Morton, a
radiation oncologist at Sunnybrook and Woman's Health Science Centre.

Men undergoing radiation for prostate cancer usually have almost daily
treatment for five to eight weeks. Side-effects from the beams striking
other tissue can include bladder and rectal difficulties and impotence.

"This enables us to give a large dose of radiation to the cancer within the
prostate while sparing the surrounding organs," Morton said Wednesday.

Researchers at Sunnybrook and Women's are in the midst of their second study
using the device for prostate cancer treatment, and the Toronto hospital is
planning trials of the computerized imaging system for women with breast and
cervical cancers.

The B.C. Cancer Agency's Vancouver Island Centre in Victoria has also begun
a patient trial to test the system, it announced Wednesday.

To set up for prostate cancer radiation, technicians begin with a single CT
scan of the man's abdomen. A 3D-ultrasound image is then taken before each
radiation session. On a computer screen, the latest ultrasound picture is
superimposed over the CT image, which allows them to see if the prostate has
moved.

The radiation beams can then be fine-tuned to strike only the gland, leaving
surrounding structures untouched.

"Most internal organs tend to move around a bit, so it's a great advantage
to be able to see at the time of treatment where the organ is that we're
trying to target, where the tumour is and where the normal tissues are
around it," Morton said during a demonstration of the technology at the
hospital.

Radiation damages both cancerous and healthy cells in the prostate. But
while the cancer cells die, healthy cells are able to repair themselves, he
added.

The $310,000 RESTITU system, which is not yet approved for routine use in
Canada, is manufactured by Montreal-based Resonant Medical.

Gary Wasserman, 57, is among 12 men with prostate cancer taking part in a
Sunnybrook study comparing the Resonant device to a standard imaging system
that uses gold seeds inserted into the prostate that show up on special
X-rays.

He chose radiation over surgery to treat his cancer, which was diagnosed
earlier this year.

"One of the advantages I found of this treatment, I actually come after
work," said Wasserman of Toronto. "I see it as (just) an inconvenience."

Dr. Eric Berthelet, a radiation oncologist at the B.C. Cancer Agency, is
leading a similar study comparing the ultrasound system versus the use of
gold seeds.

"The insertion of gold markers to track this movement (of the prostate) has
been studied and is currently in use in several cancer centres worldwide,"
Berthelet said in a release. "The ultrasound has the advantage of being a
non-invasive technique, without risks of bleeding, infection and discomfort
for our patients."

An estimated 20,500 Canadian men will be diagnosed with prostate cancer this
year; about 4,300 will die.

Morton said the ultrasound system doesn't change the amount of radiation
administered.

"The radiation effect is going to be the same. It's going to be able to
eradicate the cancer within the prostate just as well or better," he said.
"But what it can do is target it more accurately, so we're sure we're
actually covering all of the prostate with the radiation, and more
importantly, we're avoiding treating the neighbouring organs.

"So that results in better cancer control and reduced side-effects for the
patient."

Those adverse effects include bladder or rectal problems that can cause
irritation, urinary frequency and loose stools.

One of the most dreaded side-effects of radiation for prostate cancer is
impotence, which occurs when nerves and blood vessels just below the gland
are damaged.

"And once again, by being more precise in targeting the prostate, we're able
to avoid unnecessary radiation to these areas," said Morton, noting that
since impotence doesn't typically set in for about two years, it's too soon
to tell if men in the study will retain their sexual function.

Copyright © 2005 Canadian Press