June 5, 201812:50 PM ET
For many years, the death rate from cancer climbed steadily, and
the focus of big cancer meetings was the quest for better treatments to bring
malignancies under control. Cancer death rates have been falling in recent
decades, and that's allowed researchers to ask another important question: Are
some people getting too much treatment for their cancers?
The answer, from the American Society of Clinical Oncology
meeting in Chicago these past few days, is an emphatic yes.
One dramatic example revealed at the meeting relates
to the most common form of breast cancer, known as hormone-positive, HER-2
negative disease. For many women who have this diagnosis, but for whom the
disease has not spread to lymph nodes, a new study finds that anti-hormone
treatment after surgery is enough, and women won't benefit from rounds of toxic
and uncomfortable chemotherapy.
Treatment of breast cancer for this large group of women will
become easier. And for the many women who already choose not to
undertake chemotherapy, they can be reassured that it's the right
call.
Likewise, researchers from France presented evidence that people
with severe colon cancer don't benefit from a common treatment, which involves
heated chemotherapy administered at the time of surgery. This treatment has
been in use for 15 years, without good evidence that it actually works. Some
doctors were adamant about using it, while others shunned it. The study of 265
patients found that it didn't work,
says Dr. Francios Quenet, at the Regional Cancer Institute on Montpellier,
France.
The study is "an excellent example of how less is
more," when it comes to certain cancer treatments, says Dr. Andrew
Epstein, an oncologist from Memorial Sloan Kettering Cancer Center who spoke on
behalf of ASCO.
Patients with advanced kidney cancer can also be spared surgery,
according to another study presented at the meeting. "Based on studies
that were done 20-30 years ago, the patients who had their kidneys removed
lived a bit longer than the patients who did not," Dr. Bruce Johnson,
the president of ASCO and a cancer doctor at the Dana Farber Cancer Institute
in Boston, tells Shots. A study of 450 patients coordinated by researchers in
Paris found that the surgery was pointless.
Patients who had their kidneys removed did no better than those who got
chemotherapy. Those who avoided surgery were spared the trauma and the expense
of this operation.
The surgeon who presented the study at the meeting's giant
plenary session, Arnaud Mejean,
got a big cheer from the audience after he projected a cartoon at the end of
his talk, showing someone shooting himself in the foot. His point was that this
kind of study isn't in a surgeon's self-interest – but it should be done for
the interest of patients. And he suggested that all cancer physicians should ponder
what that means in their own practices.
Why are doctors giving patients challenging and unnecessary
treatments?
Johnson says one reason is that the way that cancer treatments
evolve. In the case of breast cancer, the chemotherapy was first developed to
treat advanced cancers. There, it was used aggressively to kill as much cancer
as possible. Over the years, doctors started using it for less advanced cases,
and eventually as a treatment to prevent cancer from coming back (known as
"adjuvant therapy.")
Doctors and patients already knew that it provided relatively
little advantage for many women when used as an adjuvant – perhaps reducing the
risk of cancer recurrence by just a few percentage points, for women who have a
low risk on genetic tests that can help predict the odds of a recurrence. But
narrowing down that risk even more required a huge study, involving 10,000
women and taking many years.
Drug companies, which fund many cancer studies, would have no
interest in funding that study, so the National Institutes of Health backed it,
with the help of governments overseas and advocacy organizations within the
United States.
There may be many other cancer treatments that are unneeded and
possibly even harmful. Many long-time medical practices are based on tradition
and thin evidence. But Johnson worries the federal government has been losing
interest in this kind of expensive and time-consuming research. He notes that
over the past decade, the number of studies presented at the ASCO meeting that
have been funded by the U.S. government has dropped from 575 to 143. "It's
cut in one-fourth!" he laments. "And one of the things that we think
is critically important is a robust clinical infrastructure supported by our
government."
Indeed, European researchers presented many of the big studies
at this year's meeting. There, governments seem to have more patience for
studies that can last for a decade or more, and care about research that will
save government health services the costs of unneeded treatment.
To be sure, the pharmaceutical industry is funding plenty of
studies – but mostly they aim to bring expensive new drugs on the market. There
was plenty of evidence of that at the meeting as well, both in lavish displays
where companies brag about what they hope will soon come out of their
pipelines, as well as studies showing that pricey new drugs are better than
inexpensive treatments.
In the hot field of immunotherapy alone, there are more than
2,000 drugs in development, according to Dr. Solange Peters at
Lausanne University Hospital in Switzerland and president-elect of the European
Society for Medical Oncology. The number of possible combination therapies is
mind-boggling, and it's hard to find the true winners. "Many combinations
are not based on biological mechanisms and many are likely to fail," she
said in a presentation.
Dr. Otis Brawley,
chief medical officer of the American Cancer Society, tells NPR a glut of
"me-too" drugs that don't offer meaningful advances, contributes to
some of the confusion. It's left up to doctors "to figure out the drugs we
should be using versus the drugs we should not be using."
"If I can use an auto industry example, if General Motors
develops an SUV that means Chrysler and Ford have to develop an SUV to compete
in that market, and the drug companies do the same thing, unfortunately,"
Brawley says.
He notes there are 30 companies producing very similar
immunotherapy drugs, "and one of our concerns is they're actually slowing
down the development of immunotherapy drugs by having too many drugs that are
very similar out in clinical trials." These studies all are competing for
patients, "and slowing down the completion of all the trials."
"This is a huge problem," Brawley says. "We
sometimes wish we had a policeman who could direct traffic when it comes to
drug development."
But he admits he can't figure out what that would look like,
given that the profit-driven system has worked well, in that it has brought
exciting drugs to market.
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