-21 or monosomy 21 (solely)

2002-08-01   Daniel L. Van Dyke 

1.FACMG, Cytogenetics Laboratory, Mayo Clinic, USA

Clinics and Pathology


See Acute myeloid leukemia
See Chronic lymphocytic leukemia (CLL)


Most of the AML patients were male and most over age 40 at diagnosis.


Some of the patients achieved complete remission, with survival ranging from 30+ months to 54+ months. Other patients succumbed to their disease in 2-13 months.


Four cases of CLL have been reported, with 15-41% of metaphase cells exhibiting monosomy 21 as a sole cytogenetic abnormality. Most cases were staged A/O in the Binet/Rai classification.


All five cases were males aged 45-77 years


One CLL patient exhibited a 13q deletion by FISH that was not observed in the metaphase analysis.


Survival was 77 months and 90+ months in the two cases where information was provided.


Pubmed IDLast YearTitleAuthors
85110321993Improvement of cytogenetic results in B-cell chronic lymphocytic leukemia using immuno-purified leukemic cells.Brizard A et al
9250825199711q13 rearrangement in B cell chronic lymphocytic leukemia.Brizard F et al
16384891992Monosomy 21 in two patients with acute nonlymphocytic leukemia.Chang JJ et al
26322601989Differences in bone marrow cytogenetic characteristics between treated and untreated myeloma.Clark RE et al
77801521995Cytogenetic profile of minimally differentiated (FAB M0) acute myeloid leukemia: correlation with clinicobiologic findings.Cuneo A et al
107597142000Four novel non-random chromosome rearrangements in B-cell chronic lymphocytic leukaemia: 6p24-25 and 12p12-13 translocations, 4q21 anomalies and monosomy 21.Cuneo A et al
91937551997What happens subsequently in AML when cytogenetic abnormalities persist at bone marrow harvest? Results of the 10th UK MRC AML trial. Medical Research Council Leukaemia Working Parties.Grimwade D et al
65745881983Correlation between chromosomal pattern, cytological subtypes, response to therapy, and survival in acute myeloid leukaemia.Li YS et al
37085551986Detection of clonal karyotypic abnormalities in most patients with acute nonlymphocytic leukemia examined using short-term culture techniques.Misawa S et al
65793411983Prognosis in acute lymphoblastic leukemia of childhood as determined by cytogenetic studies at diagnosis.Morse HG et al
67049431984Nonrandom cytogenetic changes in human acute leukemia and their clinical implications.Ohyashiki K et al
13779331992Frequent clonal abnormalities of chromosome band 13q14 in B-cell chronic lymphocytic leukemia: multiple clones, subclones, and nonclonal alterations in 82 midwestern patients.Peterson LC et al
38552851985Chromosomal alterations in acute leukemia patients studied with improved culture methods.Testa JR et al
31627011988Chromosome studies on 30 Chinese patients with acute nonlymphocytic leukemia in Taiwan.Tien HF et al
126998912003Monosomy 21 in hematologic diseases.Van Dyke DL et al



True monosomy 21 mosaicism can appear as the sole cytogenetic abnormality but it is rare. Many of the reported cases in the literature probably represent technical artifacts due to random loss of chromosome 21 in multiple cells by chance alone. Suspected monosomy 21 mosaicism should be confirmed by analysis of additional metaphase cells and by FISH analysis of interphase cells. Of the reported cases that are most likely to represent true clonal disease, Acute myeloid leukemia (AML) and chronic myelogenous leukemia (CML) were the most common diagnoses, with one case each of myelodyplasia (MDS), MDS/MPD (myelodysplastic syndrome), acute lymphocytic leukemia (ALL), and multiple myeloma .


Daniel L. Van Dyke

-21 or monosomy 21 (solely)

Atlas Genet Cytogenet Oncol Haematol. 2002-08-01

Online version: http://atlasgeneticsoncology.org/haematological/1225/21-or-monosomy-21-(solely)