Incidence of secondary acute myelogenous leukemia after treatment of childhood acute lymphoblastic leukemia.

BACKGROUND: Recent reports of secondary acute myelogenous leukemia (AML) occurring in children previously treated for acute lymphoblastic leukemia (ALL) prompted a review of patients with ALL treated at the Dana Farber Cancer Institute consortium (DFCI) between 1973 and 1987. Seven hundred fifty-two of 779 children treated for ALL entered complete remission. The mean follow-up time for the 752 patients was 4.4 years. Two children had AML develop 12 and 13 months after the diagnosis of ALL, respectively. METHODS: The estimated overall risk of secondary AML was calculated for the patient population as instances per 1000 patient-years of follow-up. This was compared with recent reported cases from another institution. RESULTS: The estimated overall risk of secondary AML was 0.61 instances per 1000 patient-years of follow-up (95% confidence interval: 0.15, 4.4). The difference between the risk of 0.61 among DFCI patients versus previously reported risk of 5.8 among a differently treated group of patients with ALL was statistically significant (P = 0.0008). No epipodophyllotoxin was used in the patients in the DFCI consortium. In contrast, an epipodophyllotoxin was used in 12 of 13 previously reported patients who had secondary AML develop. CONCLUSIONS: The authors concluded that the use of epipodophyllotoxins may be associated with an increased risk of having secondary AML develop in patients with ALL.