Consider Cancer's Youngest Victims
Date: December 1, 2009
The opportunity to explore the cancer genome is exciting to researchers like Donald Small who runs the Center’s pediatric cancer program. Even the most common of pediatric cancers are rare among the general population and research and corresponding research dollars are focused on the numbers—adult cancers. “There are just so many more cases of adult cancers —hundreds of thousands per year versus 10,000 to 12,000 per year,” says Small. “As a result the National Institutes of Health (NIH) cancer genome priorities have been in adult cancers.” He believes the Center’s next generation sequencing laboratory will give the pediatric cancer team an opportunity to begin looking at cancer genes involved in childhood cancers.
“EVERYONE IS LOOKING at the big cancers,” says Small. “By turning our attention to the pediatric cancers, the Kimmel Cancer Center can make a great contribution to the understanding of these diseases.”
Small is among an elite group of scientists. He uncovered a pediatric cancer culprit without the benefit of today’s sophisticated machinery and technology when
he isolated and implicated the FLT3 gene in acute myeloid leukemia. Patients whose
leukemias have this mutation do not respond well to therapy. Small’s discovery has allowed researchers to turn the tables, leading to drugs that target the mutant
gene and make the cancer cells succumb to treatment.
“I would love to be able to find other genetic targets,” he says. “For most pediatric cancers, there are no known common genetic changes, so any information will be more than what they have now.” Small believes it could change the course of some relentless
Consider Ewing’s sarcoma and patients like 13-year-old Megan McNeal.
Last winter, she noticed a lump on her thigh. An avid softball player, she thought she must have pulled a muscle, and her pediatrician agreed. But soon, she noticed it had gotten much larger. The next day a return trip to her pediatrician and further tests led to the devastating news that she may have cancer.
Instead of preparing for softball season, she was meeting with Kimmel Cancer Center surgeon and sarcoma expert Kristy Weber and having a surgical biopsy of the tumor in her thigh. It was cancer, but there was some good news. The cancer appeared to be limited to her thigh, and this meant she had a much better chance to be cured.
The next week, Megan began chemotherapy. “It was rough. I felt very nauseous for days,” she says. Four months and six rounds of chemotherapy later, her grapefruit-sized tumor had shrunk to the size of an orange and could be taken out surgically by Weber.
To kill any microscopic cancer cells that may have broken away from the tumor,
Megan received another seven rounds of chemotherapy.
Despite this and the 8-inch scar on her leg, she remained strong. In fact, she viewed her cancer as more of an inconvenience than an illness. “I’m not sick,” said Megan. “I feel fine most of the time. When you say someone is sick you think they are in bed and can’t do
anything.” She stayed focused on finishing her treatment and returning to school and the softball field. Not at all happy about being sidelined, she finagled permission from her oncologist David Loeb to rejoin her softball team and shag a few fly balls.
“I can’t say enough about this hospital; the doctors, the nurses, everyone.” says Megan’s dad Tim McNeal. The McNeals drove an hour and 20 minutes each way from their home on Maryland’s Eastern Shore for Megan’s therapy. “You hear and read about this
place, but until you experience this caliber of care yourself, you can’t really appreciate how lucky we are to have this place,” he says.
“It’s a tough unit. You know that some of these kids will never go home, but then you also see miracles every day,” says McNeal. He prayed that his daughter would be one of the miracles.
It is the true tragedy of childhood cancers. Most of these children are active and otherwise healthy, until their worlds are turned upside down with a diagnosis of cancer.
In Megan’s case, just making the diagnosis was a challenge. While her cancer looked like Ewing’s sarcoma under the microscope, it also had similarities to a different type of sarcoma called synovial sarcoma. The therapy for these two types of sarcomas are very different, so, Loeb says, more information on the biology of the cancer obtained through next generation sequencing would help greatly with diagnosis and treatment.
“There are a slew of chromosomal abnormalities associated with this cancer, but we don’t
know anything about their significance,” says Loeb. “We know that chemotherapy works better in some patients than others, but we understand so little about the molecular
biology of the cancer, we don’t know why. Clearly there are genetic differences
among patients, and we need to learn what they are.”
Right now, there is one therapy, and it is given to everyone with Ewing’s sarcoma. “We can’t intelligently choose other therapies or develop new targets because we don’t know enough about the biology of the cancer,” says Loeb. “If we did, we could identify genetic markers and distinguish those patients who can be cured with standard therapy
from those who will not.”
Despite early good news, Megan ended up among the latter group— those not cured with standard therapy. In May, follow up tests revealed that a small speck on her lung was cancer.
Additional radiation therapy and chemotherapy could not stop the progression of Megan’s cancer, and sadly, in October, she lost her battle.
Her story underscores the urgency of this research. Loeb and Small believe that sequencing the genomes of Ewing’s sarcoma and other pediatric cancers could reveal the unique genetic characteristics that cause certain cancers to grow and spread even when treated with the strongest therapies. It is knowledge that could help them save
the lives of patients like Megan.
Articles in this Issue
- Cancer Cells Revealed in a Drop of Fluid
- Cancer Causing Bacteria
- Lung Cancer In Never Smokers A Different Disease with Different Treatments
- Headline Makers In Brief
- Lab On A Chip Shows How Cancer Spreads
- New Anticancer Drug for Skin and Brain Cancers
- Colon Cancer Needs a Sugar Fix
- Internet Hoax Revealed
- Beyond Colonoscopy