A new, high-quality study reveals that the cardioprotective drug dexrazoxane significantly reduces the heart damage caused by chemotherapy received by pediatric cancer patients 15 years or more after treatment ends.
The research, which builds on previous studies at earlier follow-up times, is the first large, long-term study suggesting that receiving dexrazoxane may change how doctors should follow survivors for decades after treatment. The findings could also help steer prescribing recommendations while providing families and patients with some reassurance about the long-term effects of cancer treatment on young patients.
"When people receive chemotherapy it goes all over the body; it doesn't just go to one location. Chemotherapy does a lot of good in killing cancer cells, but it also harms our healthy cells," said Erin Mobley , Ph.D., an assistant professor of surgery at the University of Florida College of Medicine in Jacksonville and first author of the new study. "Especially in young, growing people, those healthy cells include the heart."
Mobley collaborated with the original leaders of the clinical trial, including Eric Chow, M.D., at the Fred Hutchinson Cancer Center and Steven Lipshultz, M.D., at the University of Buffalo. The researchers published their findings , which were supported in part by the National Institutes of Health and the Children's Oncology Group Aug. 6 in the Journal of Clinical Oncology.
The study followed nearly 900 childhood cancer survivors into young adulthood, including 230 survivors who had been followed for at least a decade, with almost 200 participants tracked for more than 15 years.
The researchers focused on pediatric patients receiving doxorubicin, a type of chemotherapy known as an anthracycline, for the treatment of different types of leukemia, lymphoma and sarcoma. Despite advances in cancer treatment, more than half of treatment regimens still include anthracyclines — the class of drugs most strongly associated with damage to the heart.
Half of the patients in the study received dexrazoxane, which was originally approved to help protect heart tissue in adults undergoing chemotherapy and is now commonly prescribed to children as well. Chemotherapy can expand the size of the heart's chambers, weakening the organ and potentially leading to heart failure.
In echocardiogram tests years after treatment, patients who received dexrazoxane had significantly healthier hearts. Many survivors who received the drug were able to be classified as at moderate risk of heart damage, rather than high risk. This classification could mean that survivors who received dexrazoxane during chemotherapy require less intensive screening after finishing treatment, although any potential changes to screening recommendations would require additional studies.
"Now that we've established there's this benefit, and the majority of cancer patients do receive this drug, we will hopefully be able to decrease the frequency of their echocardiograms as they age, although we need to keep studying these survivors to better understand how their cardiovascular health changes as they enter their 50s and 60s," Mobley said.
Mobley, a pediatric cancer survivor who received anthracyclines herself, said that in addition to updating screening guidelines for survivors, one of the biggest benefits of this kind of long-term study could be in helping families imagine brighter futures after treatment ends.
"It could give patients and their families a little bit of a piece of mind," she said. "It's what makes me want to get out of bed and do cancer research every day. The opportunity to make the cancer survivorship experience better for people, whether they're diagnosed at 5 or 95."
