title: Loss of heterozygosity on chromosome 6q14-q24 is associated with poor outcome in children and adolescents with T-cell lymphoblastic lymphoma.
abstract: Deletions of chromosome 6q have been reported in several hematological malignancies, but data are not conclusive regarding their biological and prognostic impact. Therefore, we focused on pediatric patients diagnosed with T-cell lymphoblastic lymphoma (T-LBL) treated uniformly according to the NHL-BFM95 protocol. We used loss-of-heterozygosity (LOH) analysis of 25 microsatellite markers located on chromosome 6q14-q24. Fragment-length analysis was performed on ABI-PRISM3100 Genetic-Analyzer. Eligibility criterion was > or =3 informative markers. Between April 1995 and March 2003, 185 T-LBL patients were treated according to the NHL-BFM95 protocol. Five-year event-free (EFS) and disease-free survival (DFS) were 79+/-3 and 87+/-3% (median follow-up 4.7 [1.2-10.1] years). Sixty-one patients were evaluable for LOH analysis, including 18 out of 23 patients with relapse. EFS and DFS were 67+/-6 and 69+/-6% for these 61 patients. Testing of 853 markers in the 61 patients identified the presence of LOH in 19 patients (31%): 13 of the 18 relapse patients and five of the 41 in complete remission (odds ratio 18.7, 95% confidence interval 4.7-75.3). One LOH-positive patient died from treatment-related toxicity. We conclude that LOH on chromosome 6q14-q24 may have conferred a high risk of relapse on our group of children with T-LBL treated according to the NHL-BFM95 protocol.
authors.affiliation: Department of Pediatric Hematology and Oncology, Justus-Liebig University, Giessen, Germany. birgit.brukhardt@paediat.med.uni-giessen.de
authors.forename: B
authors.initials: B
authors.lastname: Burkhardt
authors.forename: J
authors.initials: J
authors.lastname: Bruch
authors.forename: M
authors.initials: M
authors.lastname: Zimmermann
authors.forename: K
authors.initials: K
authors.lastname: Strauch
authors.forename: R
authors.initials: R
authors.lastname: Parwaresch
authors.forename: W-D
authors.initials: WD
authors.lastname: Ludwig
authors.forename: L
authors.initials: L
authors.lastname: Harder
authors.forename: B
authors.initials: B
authors.lastname: Schlegelberger
authors.forename: F
authors.initials: F
authors.lastname: Mueller
authors.forename: J
authors.initials: J
authors.lastname: Harbott
authors.forename: A
authors.initials: A
authors.lastname: Reiter
mesh_terms: D000293:Adolescent; D002648:Child; D002896:Chromosomes, Human, Pair 6; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000235:genetics* / Q000401:mortality; D019656:Loss of Heterozygosity; D008297:Male