A substantial proportion of childhood cancer survivors experience serious health problems as young adults, particularly those who received radiation treatment, according to a study in the June 27 issue of JAMA: The Journal of the American Medical Association, a theme issue on chronic diseases of children.
Huib N. Caron, M.D., Ph.D., of Emma Children's Hospital/Academic Medical Center, Amsterdam, presented the findings of the study at a JAMA media briefing in New York.
The introduction of more effective treatments for childhood cancer has dramatically improved survival rates, but this has been accompanied by the occurrence of late, treatment-related complications such as second cancers, organ dysfunction, and psychosocial and cognitive problems. Information is limited on the occurrence and risk of subsequent illnesses among adults who had cancer as children, according to background information in the article.
Dr. Caron and colleagues conducted a study to assess the total burden of adverse health outcomes (adverse events) following childhood cancer and evaluated treatment-related risk factors. The study included 1,362 five-year survivors of childhood cancer treated in a single institution in the Netherlands between 1966 and 1996. All survivors were invited to a clinic for medical assessment of adverse events. Medical follow-up was completed for 94.3 percent of survivors (median [midpoint] follow-up, 17.0 years). At the end of follow-up the median age of the survivors was 24.4 years, with 88 percent of survivors younger than 35 years.
The researchers found that of the 1,362 survivors, 19.8 percent had no adverse events, 74.5 percent had one or more events and 24.6 percent had five or more events. Additionally, 36.8 percent of the survivors had at least one severe or life-threatening or disabling disorder, and 3.2 percent died due to an adverse event. Almost 22 percent of adverse events were severe, life-threatening or disabling, or caused death. Of those events, orthopedic disorders occurred most often, followed by second tumors, obesity, fertility disorders, psychosocial or cognitive disorders, neurologic disorders and endocrine disorders.
Of all patients treated with radiotherapy only, 55 percent had a high or severe burden of events (defined as at least two severe events or one or more life-threatening or disabling event), compared with 15 percent of patients treated with chemotherapy only and 25 percent of patients who had surgery only. Survivors of bone tumors most often had a high or severe burden of events (64 percent), while survivors of leukemia or Wilms tumor (tumor of the kidney) least often had a high or severe burden of events (12 percent each).
In conclusion, childhood cancer survivors are at increased risk of many severe health problems, resulting in a high burden of disease during young adulthood. This will inevitably affect the survivors quality of life and also will ultimately reduce their life expectancy. Therefore, we feel that risk-stratified lifelong medical surveillance of childhood cancer survivors is needed to allow early detection of adverse events that are amenable to intervention. Future studies should focus on the efficacy of follow-up programs and other intervention strategies for adverse events, to further improve health outcomes in survivors of childhood cancer, the authors write.