A new study shows the number of childhood cancer survivors is increasing, but not all are living with a clean bill of health.

A cancer diagnosis will impact nearly 16,000 American children this year alone. The good news is that more and more kids with childhood cancers are surviving, with the majority living five years or longer after diagnosis, according to a new study from Northwestern University.

There were an estimated 388,500 survivors of childhood cancer in the United States as of January 2011, of whom 83.5 percent had lived for five or more years after diagnosis. But there’s a downside. Researchers also found that a majority of those survivors had some kind of chronic condition.

As it turns out, a clean bill of health after childhood cancer is still a very rare thing.

The study was published in Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research. The authors found that among survivors who had lived for five years or longer, 66 percent between ages 5 and 19, and 88 percent between 40 and 49, had some sort of chronic condition.

Certain conditions were more common than others. The study found that 12 percent of survivors had pain, while 35 percent had some kind of neurocognitive dysfunction. About 15 percent of survivors between 20 and 49 had self-reported functional impairment, activity limitations, impaired mental health, pain, anxiety, or fear.

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“This is the first study to estimate the number of survivors with chronic conditions at the population level,” said study co-author Siobhan Phillips, Ph.D., an assistant professor in the department of preventative medicine at Northwestern.

The study found that in survivors of childhood cancer who had lived for at least five years, about 70 percent had a mild or moderate chronic condition, while about 32 percent had a severe, disabling, or life-threatening chronic illness, Phillips said.

“When you consider that all of these estimates are based on survivors less than 50 years of age, the magnitude of these morbidities at relatively young ages is quite striking,” Phillips told Healthline. “Typically, you would not expect many of these morbidities to be a problem in the general population until older ages.”

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Instead of just focusing on the number of survivors, as researchers did in previous studies, Phillips’ team was interested in trying to understand the lives of these survivors, not just in terms of disease burden but also mental and physical function and quality of life.

“The motivation behind this was to be able to really shed some light on the magnitude of the issues affecting this population and stimulate future research,” Phillips said.

“While there have been many advances in life-saving treatments for childhood cancer, these treatments are not without consequences. This is a population experiencing co-occurring treatment benefits and morbidity,” she added.

Because these patients are so young at diagnosis, the consequences of harsh chemotherapy and radiation treatments, as well as repeat surgeries, have implications for the future, both for the patients and for the healthcare system in general.

“Therefore,” Phillips concluded, “understanding how to ensure children diagnosed with cancer not only survive but thrive is extremely important.”

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