Children with cancer have almost a 80% chance of winning a battle with cancer, as opposed to adults, and children who were diagnosed for cancer 20 to 30 years ago. A recent report has explained that despite braving odds and coming out of cancer, this does not absolve them from the risks of long-term health problems in adulthood.
One of the co-authors of the Childhood Cancer Survivor Study is a long-standing pioneer in the field. Anna T. Meadows, M.D., and colleagues at The Children's Hospital of Philadelphia were the first researchers to investigate the late effects of childhood cancer, starting in the mid-1970s. An oncologist, Dr. Meadows is the medical director of the Cancer Survivorship Program at Children's Hospital.
Dr. Meadows serves on the steering committee of the Childhood Cancer Survivor Study (CCSS), which published the research, the largest-ever study of adult survivors of childhood cancer in the Oct. 12 issue of the New England Journal of Medicine. Sponsored by the National Cancer Institute, the collaborative study drew on researchers from more than two dozen cancer centers throughout the U.S. and Canada.
In comparing more than 10,000 adult survivors of pediatric cancer to approximately 3,000 of their siblings, the researchers found survivors to be more than three times as likely to have chronic health condition, and more than eight times as likely to have a severe or life-threatening condition. The incidence of these chronic conditions increased over time and did not appear to level off over the time span that was studied.
The long-term survivors, first diagnosed with cancer between 1970 and 1986, were particularly vulnerable to second cancers, heart conditions, kidney disease, severe musculoskeletal problems and endocrine abnormalities such as thyroid disease, osteoporosis and sterility. Female survivors were at higher risk than male survivors for chronic illnesses.
One implication of the current study, said Dr. Meadows, is the need for continued medical surveillance of adult survivors of childhood cancer. "Fewer than 20 percent of these patients are followed by an oncologist or at a cancer center, but they clearly have special medical needs and higher risks," she added. There are currently 270,000 survivors of pediatric cancer in the U.S.
Dr. Meadows is nationally recognized as an expert in treatment-related effects of children's cancer. Her studies in the 1970s and 1980s showed that brain radiation used to treat children with leukemia damaged the children's cognitive development and raised their risk of later brain cancer. That research helped to change medical practice, as physicians eliminated or reduced radiation doses to the head during treatment for childhood leukemia.
Because of such studies on treatment effects, and based on many clinical trials in pediatric oncology that have led to improved treatments over the years, Dr. Meadows predicts that children diagnosed with cancer since 1987 will have fewer chronic problems as survivors than the cohort analyzed in the current study.
On the strength of her clinical and research experience with childhood cancer survivors, Dr. Meadows became the first director of the Office of Cancer Survivorship at the National Cancer Institute, serving from 1996 to 1999. She has been part of the CCSS since its inception in 1993, and chairs its publication committee, guiding the organization's output of some 50 articles.