Cancer and cardiac mortality among 15-year survivors of cancer diagnosed during childhood or adolescence

Purpose: To evaluate the impact of cardiac disease and second malignant neo plasms on late mortality rate and to identify risk factors for late mortali ty among 15-year survivors of cancer diagnosed during childhood or adolesce nce. Patients and Methods: Gender-specific all-cause and cause-specific (cardiac disease, cancer) standardized mortality ratios were calculated. Kaplan-Mei er survival estimates and Cox regression analyses were performed to determi ne the relationship of several demographic and treatment variables to survi val. Results: Patients who survived for 15 years after diagnosis had excess subs equent all-cause, cancer (second malignant neoplasms only), and cardiac mor tality rates. No decrease in the late mortality rate by treatment era (1960 to 1970, 1971 to 1984) was identified. Risk factors for moles included dis ease recurrence during the first 15 years after diagnosis, treatment with d oxorubicin, and the diagnosis of Hodgkin's disease. Those for females inclu ded treatment with radiation therapy, treatment with an alkylating agent, a nd disease recurrence during the first 15 years after diagnosis. Cox regres sion analysis demonstrated that only an initial duration of remission of le ss than 15 years (P < .01) and treatment with doxorubicin (P = .08) were si gnificantly associated with shorter survival time for males. No variable wa s significantly associated with shorter survival time for females in Cox re gression analysis. Conclusion: Fifteen-year survivors of childhood cancer have excess mortalit y. More effective treatments must be developed to reduce this excess risk. Fifteen-year relapse-free survivors did not have excess mortality. This gro up will require continued observation to determine whether excess mortality will become apparent as more events occur. (C) 1999 by American Society of Clinical Oncology.