i(22)(q10) in myeloid malignancies

2018-03-01   Adriana Zamecnikova 

1.Kuwait Cancer Control Center, Kuwait annaadria@yahoo.com


Isochromosome i(22)(q10) is a rare but non-random karyotypic change in hematologic malignancies, often associated with complex karyotypes and with partial or complete loss of chromosomes 5 and/or 7.

Clinics and Pathology


Chronic and acute myeloid malignancies

Phenotype stem cell origin

Chronic myeloid malignancies in 7 (4 males and 3 females aged 59 to 73 years, median 68 years): refractory anemia with excess of blasts in 5 (Musilova & Michalova 1988; Geddes et al., 1990; Padua et al., 1998; Martinez-Ramirez et al., 2004; Lessard et al., 2007), 1 myelodysplastic syndrome (Andersen et al., 2005) and 1 chronic myeloid leukemia (Werner et al., 1991).
Acute myeloid leukemia in 16 (10 males and 6 females; median age 61 years; range 2-76 years): 5 with M2 (Berger et al., 1987; Van Limbergen et al., 2002; Rucker et al., 2006; Xu et al., 2008; ), 2 with M4 (Shurtleff et al., 1995; Johansson et al., 1997; Asou et al., 2009; ), 1 with M5 (Gervais et al., 2008), 1 with M6 (Bitter et al., 1985) and 7 with unspecified AML (Michels et al., 1989; Pedersen & Jensen; GFCH 1996; Morrison et al., 2002; Lugthart et al., 2010; Haferlach et al., 2012; Lavallee et al., 2015).


23 patients (14 males, 9 females aged 2 to 76 years; median 63 years).


The presence of i(22)(q10) in association with chromosome 5 and/or chromosome 7 anomalies in complex karyotypes is indicator of poor prognosis, representing a therapeutic challenge.



To exclude the possibility that der(22) chromosome contain two centromeres, use of centromere 22-specific FISH probes is recommended.

Cytogenetics morphological

Sole anomaly in 1 patient, loss of 5 and/or 7 chromosomal material seemed the most common event, and their losses in combination were observed in many cases: found with del(5q)/-5 in 4, with simultaneous del(5q)/del(7q) or del(7q)/-7 in 8 and with monosomy of both chromosomes in 2. Found as an additional anomaly to inv(16)(p13q22) in 2 and with miscellaneous or highly complex anomalies in the remaining patients.

Result of the Chromosomal Anomaly


While trisomy 22 is a well know anomaly in myeloid leukemia, in particular, acute myelomonocytic leukemia with eosinophilia, i(22)(q10) is less common. The i(22q) formation leads to the gain of the entire long arm of chromosome 22 suggesting its possible role in oncogenesis. Gain of the whole long arm leads to overexpression of genes located on 22q due to a dosage effect. i(22)(q10) is mainly found as part of complex karyotypes, therefore may not be the primary disease determining aberration but rather a secondary event associated with disease evolution.


Pubmed IDLast YearTitleAuthors
156454892005Centromeric breakage and highly rearranged chromosome derivatives associated with mutations of TP53 are common in therapy-related MDS and AML after therapy with alkylating agents: an M-FISH study.Andersen MK et al
193588302009Identification of a common microdeletion cluster in 7q21.3 subband among patients with myeloid leukemia and myelodysplastic syndrome.Asou H et al
34781331987Cytogenetic studies on 519 consecutive de novo acute nonlymphocytic leukemias.Berger R et al
40635251985Rearrangements of chromosome 3 involving bands 3q21 and 3q26 are associated with normal or elevated platelet counts in acute nonlymphocytic leukemia.Bitter MA et al
89319991996Cytogenetic analysis in patients with primary myelodysplastic syndromes in leukaemic transformation. A report on 94 cases. Groupe Français de Cytogénétique Hématologique (GFCH).
20943221990Clonal karyotype abnormalities and clinical progress in the myelodysplastic syndrome.Geddes AA et al
185284282008Acute myeloid leukaemia with 8p11 (MYST3) rearrangement: an integrated cytologic, cytogenetic and molecular study by the groupe francophone de cytogénétique hématologique.Gervais C et al
221622882012ETV6 rearrangements are recurrent in myeloid malignancies and are frequently associated with other genetic events.Haferlach C et al
92643711997Deletion of chromosome arm 3p in hematologic malignancies.Johansson B et al
253311162015EVI1-rearranged acute myeloid leukemias are characterized by distinct molecular alterations.Lavallée VP et al
175749592007Fluorescence in situ hybridization analysis of 110 hematopoietic disorders with chromosome 5 abnormalities: do de novo and therapy-related myelodysplastic syndrome-acute myeloid leukemia actually differ?Lessard M et al
206608332010Clinical, molecular, and prognostic significance of WHO type inv(3)(q21q26.2)/t(3;3)(q21;q26.2) and various other 3q abnormalities in acute myeloid leukemia.Lugthart S et al
153250922004Cytogenetic profile of myelodysplastic syndromes with complex karyotypes: an analysis using spectral karyotyping.Martínez-Ramírez A et al
28049251989Refractory anemia with excess of blasts in transformation hematologic and clinical study of 52 patients.Michels SD et al
122282082002Therapy-related myeloid leukemias are observed in patients with chronic lymphocytic leukemia after treatment with fludarabine and chlorambucil: results of an intergroup study, cancer and leukemia group B 9011.Morrison VA et al
31642391988Chromosome study of 85 patients with myelodysplastic syndrome.Musilova J et al
96394161998RAS, FMS and p53 mutations and poor clinical outcome in myelodysplasias: a 10-year follow-up.Padua RA et al
20727421991Clinical and prognostic implications of chromosome 5q deletions: 96 high resolution studied patients.Pedersen B et al
168648562006Disclosure of candidate genes in acute myeloid leukemia with complex karyotypes using microarray-based molecular characterization.Rücker FG et al
77801531995Heterogeneity in CBF beta/MYH11 fusion messages encoded by the inv(16)(p13q22) and the t(16;16)(p13;q22) in acute myelogenous leukemia.Shurtleff SA et al
117469882002Identification of cytogenetic subclasses and recurring chromosomal aberrations in AML and MDS with complex karyotypes using M-FISH.Van Limbergen H et al
19322981991Cytogenetics of chronic myelogenous leukemia (CML) correlated to the histopathology of bone marrow biopsies.Werner M et al
187873512008Trisomy 22 as the sole abnormality is an important marker for the diagnosis of acute myeloid leukemia with inversion 16.Xu W et al


Atlas Image
Partial karyotypes with i(22)(q10) (A). Fluorescence in situ hybridization with LSI BCR/ABL dual color probe revealing extra copy of the BCR gene on 22q11 as a result of isochromosome formation (Abott Molecular/Vysis, US) (B).


Adriana Zamecnikova

i(22)(q10) in myeloid malignancies

Atlas Genet Cytogenet Oncol Haematol. 2018-03-01

Online version: http://atlasgeneticsoncology.org/haematological/1819/i(22)(q10)-in-myeloid-malignancies

External Links