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- Davidsson, Josef, et al.
(författare)
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Relapsed childhood high hyperdiploid acute lymphoblastic leukemia : presence of preleukemic ancestral clones and the secondary nature of microdeletions and RTK-RAS mutations.
- 2010
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Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 24:5, s. 924-31
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Tidskriftsartikel (refereegranskat)abstract
- Although childhood high hyperdiploid acute lymphoblastic leukemia is associated with a favorable outcome, 20% of patients still relapse. It is important to identify these patients already at diagnosis to ensure proper risk stratification. We have investigated 11 paired diagnostic and relapse samples with single nucleotide polymorphism array and mutation analyses of FLT3, KRAS, NRAS and PTPN11 in order to identify changes associated with relapse and to ascertain the genetic evolution patterns. Structural changes, mainly cryptic hemizygous deletions, were significantly more common at relapse (P<0.05). No single aberration was linked to relapse, but four deletions, involving IKZF1, PAX5, CDKN2A/B or AK3, were recurrent. On the basis of the genetic relationship between the paired samples, three groups were delineated: (1) identical genetic changes at diagnosis and relapse (2 of 11 cases), (2) clonal evolution with all changes at diagnosis being present at relapse (2 of 11) and (3) clonal evolution with some changes conserved, lost or gained (7 of 11), suggesting the presence of a preleukemic clone. This ancestral clone was characterized by numerical changes only, with structural changes and RTK-RAS mutations being secondary to the high hyperdiploid pattern.
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| 2. |
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| 3. |
- Ofverholm, I. Ivanov, et al.
(författare)
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PROGNOSTIC IMPACT OF IKZF1 DELETIONS IN PEDIATRIC B-CELL PRECURSOR ACUTE LYMPHOBLASTIC LEUKEMIA TREATED ACCORDING TO NOPHO PROTOCOLS - THE SWEDISH EXPERIENCE
- 2014
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Ingår i: Haematologica. - 0390-6078 .- 1592-8721. ; 99:Suppl 1, s. 9-9
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Recently, IKZF1 deletions have been shown to be associated notonly with the leukemogenic process but also to confer a poor prognosis in allrisk groups of B-cell precursor ALL. In a previous study, we used Multiplex Ligation-dependentProbe Amplification (MLPA) to investigate the presence ofIKZF1 deletions in bone marrow DNA from 116 children diagnosed with BCPALL in a single center and treated according to NOPHO protocols. Deletionswere detected in 16% of cases; both event free survival and overall survivalwere significantly reduced in the IKZF1-deleted group compared to the groupwith intact IKZF1.
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| 5. |
- Zachariadis, V., et al.
(författare)
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The frequency and prognostic impact of dic(9;20)(p13.2;q11.2) in childhood B-cell precursor acute lymphoblastic leukemia : results from the NOPHO ALL-2000 trial
- 2011
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Ingår i: Leukemia. - London : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 25:4, s. 622-628
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Tidskriftsartikel (refereegranskat)abstract
- The dic(9;20)(p13.2;q11.2) is reported to be present in similar to 2% of childhood B-cell precursor acute lymphoblastic leukemia (BCP ALL). However, it easily escapes detection by G-banding analysis and its true prevalence is hence unknown. We performed interphase fluorescence in situ hybridization analyses-in a three-step manner-using probes for: (i) CDKN2A at 9p21, (ii) 20p and 20q subtelomeres and (iii) cen9 and cen20. Out of 1033 BCP ALLs diagnosed from 2001 to 2006, 533 were analyzed; 16% (84/533) displayed 9p21 deletions, of which 30% (25/84) had dic(9;20). Thus, dic(9;20)-positivity was found in 4.7% (25/533), making it the third most common genetic subgroup after high hyperdiploidy and t(12;21)(p13;q22). The dic(9;20) was associated with a female predominance and an age peak at 3 years; 18/25 (72%) were allocated to non-standard risk treatment at diagnosis. Including cases detected by G-banding alone, 29 dic(9;20)-positive cases were treated according to the NOPHO ALL 2000 protocol. Relapses occurred in 24% (7/29) resulting in a 5-year event-free survival of 0.69, which was significantly worse than for t(12;21) (0.87; P = 0.002) and high hyperdiploidy (0.82; P = 0.04). We conclude that dic(9;20) is twice as common as previously surmised, with many cases going undetected by G-banding analysis, and that dic(9;20) should be considered a non-standard risk abnormality.
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