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| This 2008 picture provided by Georgetown University shows Richard Schlegel, M.D., Ph.D., left, and research associate Aleksandra Dakic, Ph.D., in his laboratory at Georgetown University Medical Center in Washington. A discovery allows doctors to grow "mini tumors" from each patient's cancer in a lab dish, then test various drugs or combinations on them to see which works best. Although the approach needs much more testing, researchers think it could offer a cheap, simple way to personalize treatment without having to analyze each patient's genes. "We see a lot of potential for it," said Schlegel, one of the study leaders. "Almost everyone could do it easily." (AP Photo/Georgetown University) |
It's a
medical nightmare: a 24-year-old man endures 350 surgeries since childhood to
remove growths that keep coming back in his throat and have spread to his
lungs, threatening his life. Now doctors have found a way to help him by way of
a scientific coup that holds promise for millions of cancer patients.
The bizarre
case is the first use in a patient of a new discovery: how to keep ordinary and
cancerous cells alive indefinitely in the lab.
The
discovery allows doctors to grow "mini tumors" from each patient's
cancer in a lab dish, then test various drugs or combinations on them to see
which works best. It takes only a few cells from a biopsy and less than two
weeks to do, with materials and methods common in most hospitals.
Although
the approach needs much more testing against many different types of cancer,
researchers think it could offer a cheap, simple way to personalize treatment
without having to analyze each patient's genes.
"We
see a lot of potential for it," said one study leader, Dr. Richard
Schlegel, pathology chief at Georgetown Lombardi Comprehensive Cancer Center in
Washington. "Almost everyone could do it easily."
An
independent expert agreed.
For
infections, it's routine to grow bacteria from a patient in lab dishes to see
which antibiotics work best, Dr. George Q. Daley of Children's Hospital Boston
and the Harvard Stem Cell Institute said in an email. "But this has never
been possible with cancer cells because they don't easily grow in
culture," he said.
The new
technique may reveal in advance whether a person would be helped by a specific
chemotherapy, without risking side effects and lost time if the drug doesn't
work. "Pretty nifty," Daley wrote.
In the case
of the 24-year-old, described in Thursday's New England Journal of Medicine,
lab-dish tests suggested that a drug used to treat a type of blood cancer and
some other unrelated conditions might help.
It's not a
drug that doctors would have thought to try, because the man technically does
not have cancer. But his lung tumor shrank after a few months of treatment, and
he has been stable for more than a year. He still has to have operations to
remove throat growths that keep coming back, but only about once every five months.
The man, an
information technology specialist in suburban Washington who asked to remain
anonymous to protect his privacy, has recurrent respiratory papillomatosis, or
RRP. It's usually due to infection at birth with certain types of a virus, HPV,
that causes genital warts.
The
condition causes wartlike growths in the throat, usually around the voice box.
These growths usually are noncancerous but can turn malignant, and even benign
ones can prove fatal if they spread to the lungs. The main treatment is
surgery, usually with lasers to vaporize the growths and keep them from choking
off the airway or making it hard to talk.
About
10,000 or more people in the U.S. have the disease, said Jennifer Woo,
president of the RRP Foundation. Woo, 29, is a medical student at Georgetown
and one of the researchers on the study. She also has the condition but said it
is confined to her throat and has required only about 20 surgeries so far.
The man in
the study has a much more serious case.
"I was
diagnosed when I was 3 or 4. At first, I had to have surgery every 7 to 10
days," the man said in a phone interview. "I get short of breath and
my voice will get more hoarse."
Two years
ago, the growths to his lungs became extensive and life-threatening, and his
physician, Dr. Scott Myers, described the condition at a meeting of Georgetown
hospital specialists. "It's crushing the airway," Myers said.
Doctors
suggested that the new lab method pioneered by Schlegel and others might help.
It borrows an idea from stem cell researchers: adding mouse cells for
nourishment, plus a chemical that prevents cell death to an ordinary lab
culture medium. That enabled healthy and cancerous cells to keep growing
indefinitely.
Researchers
grew "mini tumors" from the man's lung mass and from healthy tissue
and screened various drugs against them. One proved ineffective. Another worked
against the tumor but at too high a dose to be safe. The third did the trick.
A similar
approach could let doctors screen drugs for cancer patients.
"What
could be more personalized than taking this person's cell, growing it in
culture, finding a drug to treat them and then treat them?" said Doug
Melton, co-director of the Harvard Stem Cell Institute. The Georgetown method
gives an answer quickly enough that it could save lives, he said.
Tyler
Jacks, a cancer researcher at the Massachusetts Institute of Technology and
former president of the American Association for Cancer Research, said the next
step is to show that this could work for many different cancers and that it
leads to better outcomes in patients.
"It
seems to have worked in this one instance, but other tumors might prove to be
more challenging," he said.
The
National Institutes of Health paid for much of this work and has already sent
research teams to Georgetown to learn the method. About a dozen other
universities have done the same, Schlegel said.
So far, his
lab has grown prostate, breast, lung and colon cancer cells.
Georgetown
University is seeking a patent on the method.
AP Science
Writer Malcolm Ritter contributed to this report from New York.
Online:
Medical
journal: http://www.nejm.org
Throat
disease: http://www.nidcd.nih.gov/health/voice/pages/laryngeal.aspx
Marilynn
Marchione can be followed at http://twitter.com/MMarchioneAP
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