FRIDAY, June 2, 2017 (HealthDay News) -- For people who battled cancer in childhood, the prospects for a long life without cancer recurrence or chronic illness are better than ever, a new study finds.
That's largely due to changes in cancer treatment protocols that have meant less toxicity to children and less chance for long-term side effects, researchers said.
This is the first "comprehensive" study on the issue, said study author Dr. Todd Gibson, who's with the cancer control department at St. Jude Children's Research Hospital in Memphis, Tenn.
As the researchers explained, more children are surviving cancer, but the chemotherapy and radiation they receive as treatment can raise their risk for adult illness years later.
So, cancer specialists have worked hard over time to modify treatments to maximize benefits but minimize long-term risks.
And it seems to have paid off.
In the new study, Gibson's team tracked health outcomes for almost 24,000 U.S. survivors of childhood cancer. These were patients who'd survived a childhood cancer for at least five years and who were diagnosed between 1970 and 1999. All were diagnosed with a cancer prior to the age of 21.
The survivors averaged 28 years of age by the time the study was done.
The researchers found that the percentage of survivors who'd experienced a serious chronic health condition dropped from nearly 13 percent in the 1970s to under 9 percent by the 1990s.
Further analysis indicated that reductions in the amount or intensity of treatments children with cancer received was linked to lower rates of long-term illness. The study could not prove that changes in treatment caused the drop in later health problems, however.
Still, the finding held true for some of the most common pediatric cancers, including Wilms tumor, Hodgkin lymphoma, non-Hodgkin lymphoma and acute lymphoblastic leukemia, Gibson's team said. Most of the decrease in long-term illness was tied to declines in secondary cancers, hormonal issues, or gastrointestinal or neurological conditions, the research team noted.
The bottom line, according to the study authors: "Changes in childhood cancer treatment protocols have not only extended life span for many survivors, but have also reduced the incidence of serious chronic [illness] in this population."
Dr. Jonathan Fish directs the Survivors Facing Forward Program at Cohen Children's Medical Center of New York in New Hyde Park, N.Y. He reviewed the findings and agreed that recent efforts to make treatments less toxic have helped.
"This approach has been effective -- as we reduce chemotherapy, radiation and surgery exposures, long-term survivors of childhood cancer live healthier," Fish said.
But study author Gibson stressed that childhood cancer survivors still face some risk for future health issues.
"We have not identified any age or time since diagnosis when survivors no longer need to be concerned about their risk of treatment-related late health effects, as they seem to persist throughout their lifetime," he said.
The findings were to be presented Friday at the annual meeting of the American Society of Clinical Oncology, in Chicago. Findings presented at medical meetings should be considered preliminary until published in a peer-reviewed journal.
For more on childhood cancers, head to the American Cancer Society.