Thursday, June 7, 2012

Pediatrics could be model for adult cancer treatment

Nurse practitioner Christie Chaudry knows something about comforting children with cancer.

Twenty-one years ago, she was a patient herself. Chaudry was diagnosed with acute lymphoblastic leukemia, or ALL, the most common childhood cancer, when she was 12 years old. She underwent three years of intensive treatment, including multiple rounds of chemotherapy.

Like about 80% of kids with cancer today, she was cured.

"That was the inspiration for me going into medicine," says Chaudry, 33, who works at Stanford's Lucile Packard Children's Hospital, where her cancer was treated. "I've been very lucky."

Yet Chaudry might not have fared as well had she been diagnosed as an adult.

For a variety of reasons, children are far more likely to survive cancer than adults, says Stanford pediatric oncologist Michael Link, Chaudry's former physician and current colleague.

Few adult cancer survivors dare to call themselves cured. Only about two-thirds of all adult cancer patients live five years or more after diagnosis, according to the National Cancer Institute.

That's led Link and others to ask a provocative question: Could doctors improve survival rates in adults if they treated them more like children?

"Progress in the management of children with cancer is one of the great success stories of modern medicine," said Link, outgoing president of the American Society of Clinical Oncology, in a speech at the group's annual meeting in Chicago Saturday. "Pediatric oncology can serve as a model for the future, a future in which we achieve the goal of conquering cancer."

Oncologists' success with children is all the more striking given that virtually every new cancer drug is designed for grownups, not kids, says George Sledge, former president of the oncology group.

Pediatric oncologists raised the cure rate for Chaudry's type of leukemia from 20% in 1970 to 90% in 2000 � without the benefit of a single new childhood cancer drug approval, says Sledge, a breast cancer specialist at the Indiana University Simon Cancer Center in Indianapolis.

Instead, pediatric oncologists used old drugs � most developed during the Cold War� in new ways, carefully testing different doses and combinations, Link says.

Those slight alterations saved lives.

Today, pediatric oncologists "are more regimented in how they deliver care, and I mean that in a good way," says oncologist David Johnson, chair of internal medicine at the University of Texas Southwestern School of Medicine in Dallas. "It's like flying a plane where they go through a checklist and they make sure every switch is flipped."

Pediatric oncologists also pioneered the field of "survivorship care," Link says. Because so many survive their disease, doctors have been able to study their health as they grow up and enter middle-age. Many larger hospitals are opening survivorship centers to address their needs, such as early mammogram screenings for women who received chest radiation as children, which increases the risk of breast cancer. Adult oncologists in recent years have begun to consider how toxic treatments affect patients long-term, addressing how the early menopause caused by some chemotherapy drugs and surgeries, for example, affects a woman's long-term risk of heart disease and bone fractures.

Most critically, pediatric doctors let no child die in vain.

They enrolled 50% to 80% of young patients in a clinical trial, sharing their research findings with colleagues around the country, Sledge says.

"Imagine if we could learn from every patient," Link said in his speech.

That's not happening today.

Only 3% to 4% of adult cancer patients join clinical trials, Sledge says.

That makes it harder for doctors to know what's working and what's not, and to find something better, Sledge says.

By necessity, pediatric oncologists had to collaborate, says Stephen Sallan, a pediatric oncologist and chief of staff at Boston's Dana-Farber Cancer Institute.

That's because cancer in children is mercifully rare, with about 12,500 cases in kids a year, compared with 1.5 million in adults.

Even at a big urban hospital, a cancer specialist might see only a handful of cases of a particular type of pediatric cancer a year, Link said. So doctors had no choice but to reach out to their colleagues across the country for guidance in finding the best treatment and in organizing research studies, Link said.

That sort of teamwork has become part of the culture, Sallan says.

Yet translating medicine's success with children into the adult world isn't simple.

Just enrolling adults in trials is more of a challenge, Sledge says.

That's because children tend to be treated at large university hospitals in big cities � the only places with enough specialists to treat a disease as rare as pediatric cancer � where doctors are expected to lead research, Link says.

Among adults, most patients are treated by community doctors who may have never participated in a clinical trial.

Many insurance plans refuse to pay for treatments provided through a clinical trial, Sledge says. Even when pharmaceutical companies provide experimental drugs for free, insurance companies often refuse to pay for other care that they might normally provide if patients weren't in clinical trials, such as surgeries, chest X-rays or other drugs, Sledge says.

Those policies could change soon. The Affordable Care Act requires insurers to cover treatments provided through clinical trials, Sledge says. The Supreme Court is considering whether that law is constitutional.

Adult cancers also tend be tougher and more genetically complex, with more mutations than children's cases, making them harder to treat, Sledge says.

Children, whose resilience is legendary, can often withstand harsh treatments and high doses that elderly or even middle-aged adults can't tolerate, Johnson says.

Parents typically are devoted in caring for children with cancer, making sure they attend every appointment and take every pill on time, Johnson says. Adults rarely take equally good care of themselves.

Yet Link said he hasn't given up hope.

Over the past year, the oncology group has begun working to build a formal network for adult oncologists, much like the groups that children's doctors created decades ago, to make it easier for physicians to share data and learn from each other.

Link, 63, said he's been in practice long enough to have seen many of his patients grow up. He's attended their weddings. He's consulted with one, now a doctor, when the young man called to ask about tricky cases.

Saving those lives � and giving kids the chance to grow up � makes up for the pain of treating children who can't be saved, Link says. "These relationships are magical. These kids � they're well until they're sick," he says. "But then, you can do something about it, and hopefully, they go on with their lives."

Chaudry, Link's prot�g�, feels the same calling.

"The reason I love this is that kids always want to be kids," says Chaudry of Mountain View, Calif. "No matter how crummy they feel, they will make their best effort to get out of bed and do what makes them happy. I feel a certain privilege to be there and be with them and share the little bits and pieces of what I learned. � You just feel like you've really helped someone."

Chaudry has built special relationships with her patients.

She recalls talking to a 14-year-old who was depressed about losing her hair. Though she doesn't always reveal her cancer history, Chaudry decided to open up this time. "I said, 'My one regret is that I didn't take control of the situation and just get rid of it all.' "

When Chaudry saw the girl again, the teen had a freshly shorn head � and a big smile. She wore a beautiful, brightly colored scarf. "She was really proud of herself," Chaudry says. "Having any sense of control in such an uncontrolled situation is really powerful."

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