INDIANAPOLIS (AP) - When doctors diagnosed Billy Stamm with lung
cancer, there was more bad news to come. Not only was surgery out
of the question, the odds weren't good that he would respond to
conventional radiation therapy.
Stamm's frail lungs were so ravaged by years of emphysema,
bronchitis and a two-pack-a-day cigarette habit, that radiation
therapy to kill the tumor also would have injured healthy tissue.
But the Connersville service station worker wasn't without hope.
One of his doctors told him about an experimental therapy being
tested at the Indiana University School of Medicine. It used
precisely aimed high doses of radiation to try to kill tumors while
sparing healthy tissue.
Stamm's doctors said there was a chance the tumor in his right
lung wouldn't spread if he chose no treatment. But the 57-year-old
decided to give the new therapy a shot.
``I said `I'm game for just about anything right about now,'''
said Stamm, who was diagnosed in November. ``It sounded like
something worth giving a try. I didn't want to wait and do
nothing.''
In June, Stamm became the seventh patient with inoperable lung
cancer to receive the new treatment - stereotactic body
radiotherapy - as part of a clinical trial at the Indianapolis
school.
The first tests of the new therapy are aimed only at determining
the highest radiation level that can safely be given to the 35 or
so patients expected to participate.
But the hope is that it will lead to a second clinical trial
that will reveal it as a potent treatment for inoperable, early
stage lung cancer, according to Dr. Mark Williams, the trial's
principal investigator.
``We're hoping this can become another option for a patient
group that has few options,'' said Williams, a clinical assistant
professor at IU.
For lung cancer patients whose disease is in the early stage,
the survival prospects between those who undergo surgery to remove
tumors and those who can't is stark.
Patients who undergo surgery have a cure rate between 50 to 70
percent. But for patients with inoperable tumors who get
conventional radiation instead, the cure rate is only 20 to 30
percent.
Considering those numbers, a more effective radiation therapy
would be an important development, said Dr. Robert D. Timmerman, an
assistant professor of radiation oncology at the medical school.
Since the therapy was first used to treat a patient in the
United States, at IU in 1997, it has extended the predicted
lifespans of liver, colon and breast cancer patients whose cancer
had spread, he said.
Timmerman, the trial's co-principal investigator, anticipates
improved results in the clinical trials because its subjects all
have lung cancer that hasn't spread to other organs.
The new therapy taps into several advanced technologies,
including 3-D imaging, radiation beams that can be tailored to the
shape of the tumor and a new way to hold patients virtually
motionless to target the cancer.
A similar approach is used to effectively target brain tumors.
But it wasn't easy to transfer that technology beyond the cranium's
fixed tissues because tissue in the body's torso tends to shift,
Timmerman said.
The new therapy solves that problem with a special body frame
designed in Sweden to hold patients extremely still.
The patient lies on a Styrofoam body pillow that, when the air
inside it is vacuumed out, creates a mold of the patient. The
pillow is saved and used in subsequent treatments to place the
patient in the same position.
A device Timmerman likens to an apple press is pressed against
the patient's chest to restrict breathing as minute adjustments are
made to the body frame before photon radiation is fired at the
cancer.
Because positioning each patient for the treatments can take up
to an hour, some need sedatives to remain still for so long,
Timmerman said.
But the long wait is worth it because the cancer can be
precisely targeted, he said.
While in conventional radiation therapy, radiation can only be
focused at areas with diameters of 1.2 inches (3 centimeters) to
1.5 inches (3.8 centimeters)- threatening healthy tissue - the new
therapy can hit targets two-tenths of an inch in diameter.
That's possible with technology similar to that used to target
missiles. During an MRI or CAT scan, coordinates are assigned
throughout the patient's body to create a grid system that allows
the tumor's location to be known precisely when the patient is in a
specific position.
Once the tumor is in the crosshairs, it is blasted with
radiation from seven directions. Another innovation permits the
radiation beams to be tailored to the tumor's shape.
``If we have a tumor shaped like a banana, we can aim the beams
into the shape of a banana,'' Timmerman said.
The same technology allows the highest radiation levels to be
focused at the tumor's center, with the intensity falling off
rapidly farther out.
The new therapy offers hospital-weary patients another benefit.
While patients in conventional radiation therapy receive about
35 separate treatments over a six-week period, the new treatment
requires just three treatments over about a 10-day period.
To gauge the safety of the therapy's intense radiation, the
researchers are slowly increasing the radiation levels. Patients in
the latest group received in a single treatment about six times the
radiation of a conventional treatment.
If the therapy works, it will give oncologists a valuable new
weapon because early detection of lung cancer is improving, said
Dr. Norman H. Edelman, a scientific consultant for the American
Lung Association.
``The concept is good and I'll be waiting anxiously to see what
their results are,'' said Edelman, dean of the School of Medicine
at State University of New York at Stony Brook.
Stamm, his wife, Millie, and son, Gene, 30, also are awaiting
results.
Since his last treatment in late June, Stamm said he is faring
well.
``I'm feeling good, real good. No sickness or nothing. I think I
even feel a little better, but we'll see,'' he said.
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On the Net: www.radonc.iupui.edu
