Cancer is not only a disease that strikes adults. In fact, it now kills more American children past the age of infancy than any other illness, according to the National Cancer Institute (NCI). Over the past 35 years, the rate of cancer in youngsters has increased annually. In all, about 11,000 new cases of childhood cancer are expected to be diagnosed this year — about half will be acute lymphocytic leukemia (ALL), brain, and other central nervous system tumors, and neuroblastoma (cancers that begin in nerve cells).
But despite these worrisome statistics, there is good news about kids and cancer. The five-year survival rate for all childhood cancers combined has increased dramatically. It rose from 60 percent in the 1970s to almost 90 percent in recent years, the NCI reports.
This improved outlook is the result of changes in pediatric cancer treatments, along with improved follow-up care for young cancer survivors, according to the Childhood Cancer Survivor Study headed by investigators at St. Jude Children’s Research Hospital. The researchers studied 34,033 childhood cancer survivors whose disease was diagnosed and treated between 1970 and 1999, when the patients were 20 years old and younger. The analysis revealed the steadily decreasing death rate for these youngsters since 1970 coincided with changes in pediatric cancer therapy and follow-up care.
Side effects from several cancer therapies can leave young patients at increased risk for serious and even life-threatening medical conditions (including additional cancers, lung problems, and heart failure) that may not develop until years after initial cancer treatments are finished. And for certain childhood cancers with low cure rates, like high-risk neuroblastoma and bone tumors, aggressive treatments remain the best available treatments, despite the risks from strong doses of chemotherapy and intensive radiation.
But for other forms of cancer, gentler therapies have been shown to be effective — and these less toxic treatments are helping save lives, according to the St. Jude research.
Young patients who benefited the most from this evolving therapy were those diagnosed with ALL, Hodgkin lymphoma, or Wilms tumor (a form of kidney cancer) — malignancies that make up about 30 percent of all childhood cancers diagnosed annually in the U.S. Thanks in part to a reduction in the use and dose of radiation therapy and chemotherapy drugs called anthracyclines to treat these diseases in recent years, the five year survival rate for kids with these three cancers is currently 90 percent or better, according to the American Cancer Society (ACS). (The ACS offers resources, news and support for families coping with childhood cancer.)
Youngsters with ALL have benefited especially from the change in cancer treatment. St. Jude researchers published evidence in 2009 that pediatric ALL is curable without treating the brain with radiation. Now children with ALL are not given radiation therapy and are far more likely to survive than in previous years.
“These results suggest that we have learned how and when to back off of therapy, and we are better about recognizing and managing the late effects of treatment,” said Greg Armstrong, MD, of St. Jude’s Department of Epidemiology and Cancer Control, who headed the study. “The bottom line is that childhood cancer survivors in more recent eras are living longer.”
As children who have been treated for cancer grow up, they now have better follow-up care than in previous years — including screenings that zero in on any increased health risks caused by past treatments.
“For survivors at risk of breast cancer due to chest radiation or heart problems because of anthracyclines, screening tests like mammograms, and echocardiograms that result in early detection of late effects of cancer therapy may make a lifesaving difference,” Armstrong explained.
September 11, 2015
Christopher Nystuen, MD, MBA