Mortality experiences among 15+ year survivors of childhood and adolescent cancers

Abstract

Background: Studies of childhood and adolescent cancer survivorship have tended to focus on limited survival intervals (e.g., 5 and 10 years). Our report evaluates gender-specific overall mortality, as well as mortality by age group, and by cause, among 15+ year survivors of cancer diagnosed during childhood or adolescence.

Procedure: This was a retrospective cohort study of 565 15+ year childhood cancer survivors from Roswell Park Cancer Institute's Long-Term Follow-Up Project. Sex- and age-specific person-years at risk were accumulated and applied to age-specific mortality rates for New York State, excluding New York City. Standardized mortality ratios (SMRs), and 95% confidence intervals, were calculated and compared to mortality risks of the general population.

Results: Second malignancy was the leading cause of death among male and female survivors (15/38 deaths, 39%). Excess overall mortality was noted among both males (SMR = 284) and females (SMR = 371). Significant mortality excesses were seen in both genders for deaths due to primary malignant neoplasms and secondary malignancies, as well as cardiac deaths among males. Excess mortality was noted across most age strata. In the scenario of no cancer relapse, overall mortality in both genders did not differ significantly from the general population.

Conclusions: Long-term survivors of childhood and adolescent cancers continue to demonstrate significant excess mortality. However, overall mortality among 15+ year survivors without a relapse appears to be comparable to the general population. The leading cause of death among 15+ year survivors is second malignancy in this study, which represents a novel and important finding in terms of long-term follow-up.