NEW YORK, Oct 06 (Reuters Health) -- The vast majority of children with cancer now survive their disease for at least 15 years. However, researchers caution that specific childhood cancer therapies may increase risks for fatal heart attack or secondary cancers as these patients enter adulthood.
For example, "the relative risk of death due to cardiac disease is approximately 66 times that of the general population for those males treated with (the cancer drug) doxorubicin," according to study lead author Dr. Daniel Green of the Roswell Park Cancer Institute and State University of New York, in Buffalo. The findings were published in the October issue of the Journal of Clinical Oncology.
"Advances in treatment have increased the survival rate of children and adolescents with cancer dramatically," the investigators write. Their examination of the treatment and long-term survival of over 1,400 pediatric cancer patients found that 88% survived at least 15 years after diagnosis.
However, these patients still had significantly higher risks for death as adults compared with the general population, especially when it came to deaths due to either heart attack or secondary cancers. Among male patients, two factors -- early cancer recurrence (less than 15 years) and treatment with doxorubicin -- were most closely linked to this increase in risk. For females, early recurrence and exposure to radiation therapy were associated with increases in adult death risk.
According to the researchers, previous studies have linked the 'megavoltage' radiation used in cancer therapy with a "significant risk" for heart attack. And they point out that the negative cardiac effects of some chemotherapy treatments "may only be apparent in the course of pregnancy or with initiation of a vigorous physical training program."
The findings may prompt efforts at altering therapy dosages, the researchers note. In a Journal statement, Green explained that "studies like these can help guide changes in therapy that will maintain cure rates while improving long-term survival."
