Acute lymphoblastic leukemia occurring as a second malignant neoplasm in childhood: report of three cases and review of the literature.

PURPOSE: The long-term effects of childhood cancer and its therapy are a problem of increasing concern. One of the most important of these late effects is the development of second malignant neoplasms (SMNs), which occur in approximately 8% of children within 20 years of diagnosis of a malignancy. These secondary cancers may result (individually or in combination) from increased genetic susceptibility, the mutagenic effects of chemotherapy and/or radiation therapy, or chance. Whereas the development of acute nonlymphocytic leukemia (ANLL) as an SMN is a well-recognized phenomenon, acute lymphoblastic leukemia (ALL) has been infrequently described as an SMN in either adults or children.

PATIENTS AND

METHODS

We report three patients treated at our institution in whom ALL developed as an SMN after treatment for neuroblastoma, Wilms' tumor, and Hodgkin's disease. These cases prompted us to review the published literature for cases of secondary ALL in childhood. Patients whose initial malignancy was diagnosed at age less than 16 years were classified as pediatric patients. SMNs were defined as cancers of clearly distinct histologic type occurring 6 or more months after diagnosis of the first malignant neoplasm.

RESULTS

Including the three index cases, a total of 18 children with secondary ALL are reviewed, and the clinical features are discussed and compared with those of secondary ANLL.

CONCLUSIONS

This review summarizes the published case histories of secondary ALL. The data suggest that ALL represents approximately 5% to 10% of the cases of acute leukemia that arise as SMNs in both adults and children.