Childhood Cancer Survivors Continue To Have Higher Mortality Rates than the General Population

The proportion of childhood and adolescent cancer patients who survive five years after their diagnosis has been growing over the last four decades. However, past studies indicated that these individuals continue to have excess morbidity and mortality due to their original disease and treatments.

To find out what the long-term risk of death is for these individuals, Ann Mertens, Ph.D., of Emory University and Children's Healthcare of Atlanta and colleagues examined data from 20,483 five-year survivors who were diagnosed with childhood or adolescent cancer between January 1, 1970 and December 31, 1986 and enrolled in the Childhood Cancer Survivor Study.

The researchers searched the National Death Index and state death records for deaths occurring between January 1, 1976 and December 31, 2002. With that information, they calculated cause-specific mortality rates and the overall ratio of observed deaths relative to the number of expected deaths in the general population, which is called the standardized mortality ratio.

During the follow-up period, 2,821 (13.8%) of the five-year survivors died. The overall standardized mortality ratio was 8.4 and the absolute excess risk of death from any cause was 7.36 deaths per 1,000 person-years. Of the 2,534 individuals whose cause of death could be identified, 57.5% died due to disease recurrence. When compared with what would be expected in a population of this age group, substantial increases in deaths due to subsequent malignancy, heart disease, and pulmonary problems were found.

"In conclusion, children and adolescents diagnosed with cancer continue to be at elevated risk for death due to recurrences of the primary disease, and as a result of late effects of therapy," the authors write.