Hematological malignancies with a deletion of 11q23: cytogenetic and clinical aspects

Abstract

Balanced translocations of 11q23 are associated with specific clinical features and a poor outcome, but the relevance of deletions involving 11q23 is not clear. Fifty-seven patients with this deletion were collected by the Workshop, 30 had terminal and 27 had interstitial deletions. Twenty-seven patients had acute lymphoblastic leukemia (ALL), 16 had acute myeloid leukemia (AML), one had acute biphenotypic leukemia, one had acute undifferentiated leukemia and 12 had myelodysplastic syndrome (MDS). ALL patients had a median age of 7 years, median white blood cell count (WBC) of 15 × 10 9 /l, and 10/24 had common ALL. AML patients had a median age of 23 years, a median WBC of 49 × 10 9 /l, and 9/16 had M4 or M5. MDS patients were all adult, median age of 69 years, median WBC of 3 × 10 9 /l, and 7/12 had refractory anemia. The clinical outcome depended on diagnosis: children with ALL had a better prognosis (4/16 relapsed, one died) than AML patients; all adults and children with AML and 5/12 MDS patients died. Fluorescence in situ hybridization (FISH) identified 3 del(11q23) as translocations or insertions. Molecular studies revealed a MLL rearrangement in 8/10 patients. Because the involvement of MLL might be of prognostic relevance, identification of a del(11q23) should be an indication for FISH and molecular studies.

Expression of the human homologue of rat NG2 in adult acute lymphoblastic leukemia: close association with MLL rearrangement and a CD10−/CD24−/CD65s+/CD15+ B-cell phenotype

“…This parallels findings from the European Union Concerted Action Workshop on 11q23: among ALL patients with t(4;11)(q21;q23) 15% (26/173) were classified as pre-B ALL and del(11)(q23) has also been demonstrated in pre-B-ALL. 22,23 Thus, the close association between NG2 positivity and the presence of MLL rearrangement in these nine patients with pre-B-ALL strongly suggest that these patients are at an increased risk for treatment failure. The fact that none of our patients with mature B-ALL and T-ALL showed NG2 expression corresponds to previous findings.…”

Deletion of 11q23 is a highly specific nonrandom secondary genetic abnormality of ETV6/RUNX1-rearranged childhood acute lymphoblastic leukemia

“…Patients with an 11q23 deletion in which an entire MLL allele may or may not be eliminated account for approximately 20% of the 11q23-rearranged cases. 2,3 Although there are limited data on the biological and clinical characteristics as well as the prognosis of a del(11)(q23) in pediatric ALL, a few previous studies showed that this abnormality was commonly associated with low-risk features at presentation and survival rates of approximately 75%. 2,3 The detection of several cases with such 11q deletions during our screening program for secondary genetic abnormalities in ETV/RUNX1 þ B-cell precursor (BCP) ALL led us assess the incidence as well as the clinical, laboratory and biological features of 11q23-deleted cases in a population-based cohort of consecutively registered BCP ALL patients.…”

“…2,3 Although there are limited data on the biological and clinical characteristics as well as the prognosis of a del(11)(q23) in pediatric ALL, a few previous studies showed that this abnormality was commonly associated with low-risk features at presentation and survival rates of approximately 75%. 2,3 The detection of several cases with such 11q deletions during our screening program for secondary genetic abnormalities in ETV/RUNX1 þ B-cell precursor (BCP) ALL led us assess the incidence as well as the clinical, laboratory and biological features of 11q23-deleted cases in a population-based cohort of consecutively registered BCP ALL patients. 4 Between 22 September 1986 and 31 May 2005, 948 previously untreated children and adolescents up to 18 years of age diagnosed with ALL were enrolled in four consecutive multicenter trials of the Berlin-Frankfurt-Mü nster (BFM) group: ALL-BFM-A (Austria) 1986 (n ¼ 142), ALL-BFM-A 1990 (n ¼ 256), ALL-BFM-A 1995 (n ¼ 230) and ALL-BFM-A 2000 (n ¼ 312).…”

Comparison of cytogenetics, Southern blotting, and fluorescence in situ hybridization as methods for detecting MLL gene rearrangements in children with acute leukemia and with 11q23 abnormalities

“…69 In part, the conflicting findings may have resulted from different laboratories using different probes for FISH and Southern blotting analysis.…”