A year ago, when
Gayle Driscoll's, breast cancer recurred on her
skin, the 63-year-old retired teacher from
Barnstable tried an experimental treatment that gave
her radiation therapy some extra oomph . Every time
she lay down for radiation treatment on her chest,
her tumors were also heated with a special device
that emitted radio frequency waves. After six
weeks, the skin tumors were gone.
The heat therapy
called hyperthermia was meant only as a local
treatment -- and the cancer ultimately spread to her
bones -- but it was “psychologically important” to
her to see the tumors in her skin disappear, she
said.
Hyperthermia, in
which microwaves are used to raise the temperature
of a tumor or the patient's whole body to 104 to 106
degrees Fahrenheit, is a new twist on an old
treatment idea that has gained new currency recently
thanks to some successful studies.
Hypothermia
significantly boosts the killing power of
chemotherapy and radiation. It is generally used to
help prevent local recurrences, but some doctors
speculate that may improve overall survival as well.
. At least eight studies in recent years have shown
that adding hyperthermia to chemotherapy or
radiation can improve local control of cancers of
the esophagus, cervix, head and neck, brain,
melanoma and breast cancers that have spread to the
chest wall, said Dr. Mark Dewhirst, director of the
hyperthermia program at Duke University Medical
Center in Durham, N.C.
Scientists who have
observed first hand the effects of hyperthermia are
impressed. “I’m amazed at some of the tumors that
just melt away with the combination of radiation and
heat,” said Dr. David Wazer, radiation oncologist in
chief at New England Medical Center.
At Long Beach
Memorial Medical Center in California, Dr. Nisar
Syed, director of radiation oncology, has treated
more than 3,000 patients with hyperthermia plus
radiation over the years. In many cases, “we saw
rapid regression of the tumor,” he said, and in some
cases, improved survival as well.”
In the future,
hyperthermia could turn out to be among the most
powerful anti-cancer weapons yet. Consider this
idea, now being studied at
Duke: Researchers
have created a tiny bubble, or liposome, with water
on the inside and a ring of fat on the outside.
Mixed in with the water is a chemotherapy drug,
doxorubicin. The liposome is designed to be stable
at body temperature but to burst when heated. By
using hyperthermia to explode the liposomes,
Dewhirst has shown in mice that doctors can deliver
30 times more chemotherapy than would otherwise be
possible.
Scientists think
hyperthermia probably fights cancer in several ways.
“When you combine
heat and radiation, the cell-killing of cancer cells
is better,” said Dr. Jay Harris , chairman of
radiation oncology at both Dana-Farber and Brigham
and Women’s Hospital.
Radiation works by
damaging DNA. But there must be enough oxygen nearby
for this damage to occur. Parts of tumors are tough
to kill because they have a poor blood supply and
thus, low oxygen levels. Raising the temperature of
a tumor brings more blood, hence more oxygen, to the
tumor.
With chemotherapy,
drugs get in through small channels on the cell
surface. “The heat opens these channels so that
chemotherapy drugs can more easily enter in,” said
Wazer of New England Medical Center.
Hyperthermia also
seems to “jump-start the immune response,” at least
in mice, said Elizabeth Repasky, an immunology
professor at the Roswell Park Cancer Institute in
Buffalo, N.Y., who is now looking at the effects in
humans. Just as a fever with the flu may boost
immune response, so may hyperthermia, a kind of
artificial fever.
The idea of using
heat to treat cancer started more than 100 years ago
when an American surgeon, Dr. William B. Coley,
noticed that some cancer patients who also had high
fevers from bacterial infections had their tumors
shrink. He began inducing fevers on purpose in
cancer patients by infecting them with bacteria.
Several decades ago,
a number of medical centers, including Dana-Farber
and Johns Hopkins Medical Institute, began pursuing
the idea -- with disappointing results. Insurance
payments for the procedures were low and a major
study about 15 years ago showed no benefit to
hyperthermia, though the study was highly flawed.
“So the technique
was by and large abandoned,” said Wazer of NEMC.
The good news is
that today, reimbursement rates are rising and the
instruments that can deliver microwaves even to
tumors deep into the body are more precise. In the
last few years, new , better-designed studies “have
rekindled interest” in the idea, said Harris.
Moreover, the National Cancer Institute recently
opted to grant $19 million to Duke to continue its
hypothermia research.
Among the studies
turning the tide for hyperthermia is one published
last year by Dr. Ellen L. Jones, a Duke radiation
oncologist. Writing in the Journal of Clinical
Oncology, her team reported that, compared to
patients getting radiation but not hyperthermia,
those who got both had a significantly reduced the
risk of recurrence of“superficial” tumors, chiefly
breast cancers that had spread to the chest wall.
“I really trust the
data coming out of this Duke group,” because the
team was so meticulous, said Harris, who was not
involved in the study.
In another study of
68 women with cervical cancer in the US, Norway and
the Netherlands, also published last year, Jones and
colleagues showed that a triple combination -–
hyperthermia, radiation and chemotherapy –- was
highly effective at lowering the risk of recurrence.
A larger study comparing this triple treatment with
standard treatment is now underway.
Dr. Joan M.C. Bull ,
director of thermal therapy research at the
University of Texas Medical School at Houston is
even pursuing whole-body hyperthermia for some kinds
of cancers, including metastatic pancreatic cancer.
Bull places patients, head and all, inside a radiant
heat machine that brings body temperature to that of
a high fever, about 104 F. It’s very safe, she said,
though patients are monitored carefully. Some
patients get “cranky” during the treatment, she
said, as they might with a fever.
Working with rats,
Bull has heated the body for about six hours, and
found that chemotherapy can be given before, during
and after heat treatment. Her early,
still-unpublished, results “appear promising,” she
said, particularly for cancers that have spread
beyond a local area.
Clearly, more
research is needed. But many regions now have at
least one center. In Boston, it’s New England
Medical Center; in Providence, a center is about to
open at Rhode Island Hospital.
So if you or a loved
one is getting treated for cancer, it's worth asking
a doctor if hyperthermia might help.
Judy Foreman’s
column appears every other week. Past columns are
available on
www.myhealthsense.com .
Note: the picture
is courtesy of
Jack Gallagher Ueland Illustration Co.
www.uelandillustration.com
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