Abnormalities of chromosome bands 15q13-15 in childhood XXXX .

@entity1 @entity1778 @entity981 @entity5
BACKGROUND: Recurring breakpoints in chromosome bands 15q13-15 occur infrequently in @entity1778 . To the authors' knowledge, the clinical significance of these breakpoints in childhood @entity981 ( @entity981 ) has not been previously investigated. METHODS: Centrally reviewed karyotypes of @entity1 with newly diagnosed @entity981 enrolled on @entity1 's @entity5 Group protocols from 1988 to 1995 formed the basis of the current report. Statistical analyses used chi-square tests for homogeneity of proportions, and outcome was analyzed using life table methods and associated statistics. RESULTS: Of 1946 cases with centrally reviewed and accepted cytogenetic analyses, 23 cases (1%) had breakpoints in chromosome bands 15q13-15. Most @entity1 with 15q13-15 breakpoints had standard risk @entity981 , although breakpoints in 15q13-15 occurred more frequently in @entity1 than in older @entity1 . The majority of these @entity1 (16 @entity1 ; 70%) had balanced 15q13-15 rearrangements. Additional chromosomal abnormalities not involving 15q included abnormal 12p, abnormal 9p, Philadelphia chromosome, deletion 6q, and an 11q23 breakpoint. Thirteen (57%) 15q13-15 breakpoints occurred in pseudodiploid karyotypes; five (22%) were in hyperdiploid karyotypes with 47-50 chromosomes; two (9%) were in hyperdiploid karyotypes with > 50 chromosomes; and three (13%) were in hypodiploid karyotypes. Of the 23 @entity1 with 15q13-15 breakpoints, 21 were survivors, 18 survived event-free for 2.2-9.3 years, and 3 were alive 1 to 3 years after a relapse at time of writing. CONCLUSIONS: The current study suggests that genes at 15q13-15 may be involved in the leukemogenesis of some cases of @entity981 , but that with current intensive therapy such aberrations do not confer increased risk of treatment failure.
