Late mortality of long-term survivors of childhood cancer.

Abstract

PURPOSE To determine the frequency and patterns of late mortality among long-term survivors of childhood cancer. MATERIALS AND METHODS Medical records of patients who survived at least 5 years after the diagnosis of childhood cancer were reviewed to determine the causes of subsequent deaths. Estimated 15-year survival and standardized mortality ratios for deaths from nonneoplastic treatment complications were compared with adjusted United States population estimates. The study included 2,053 patients who had survived > or = 5 years, grouped by treatment eras that reflected increased intensity of therapy and significantly improved survival (early era, 1962 to 1970; recent era, 1971 to 1983). RESULTS There have been 258 subsequent deaths in the 2,053 childhood cancer survivors; 169 occurred 5 to 10 years postdiagnosis and 89 > or = 10 years post diagnosis. For the study period as a whole, deaths were attributed to recurrent primary malignancy in 61% of cases, second malignancy in 20%, nonneoplastic treatment complication in 10%, and unintentional injury/suicide in 8%. Late death from recurrent disease decreased significantly for survivors treated in the recent era (P < .0001), while the risk of death from second malignancies increased, although not statistically significantly (P = .10). Projected 15-year survival estimates for all > or = 5-year survivors in both treatment eras was greater than 90%, but differed from expected rates. CONCLUSION Late mortality from recurrence after treatment for childhood cancer decreases with more effective initial therapy. Prolonged disease-free status is associated with an expected survival that approaches that of the general population for patients treated from 1971 through 1983. The impact of more recent intensified and novel therapies for high-risk patients remains to be determined.