[Characteristics and outcome of chromosomal abnormalities in Ph negative cells of chronic myelogenous leukemia patients treated with tyrosine kinase inhibitors].

OBJECTIVE: To investigate cytogenetic features and outcome of chromosomal abnormalities in Philadelphia negative cells (Ph(-)CAs) of chronic myelogenous leukemia (CML) patients treated with tyrosine kinase inhibitors. METHODS: Clinical and laboratory data of 15 CML patients in which Ph(-)CAs occurred after tyrosine kinase inhibitors therapy were collected and analyzed. RESULTS: Of 15 cases with Ph(-)CAs, 12 patients were treated with imatinib, 2 were treated with dasatinib and 1 was treated with bosutinib. + 8 was the most common abnormality in Ph(-)CAs, which accounted for 46.7% of all. Ph(-)CAs usually occurred when Ph(+)cells decreased or disappeared due to tyrosine kinase inhibitors therapy. The average time for the appearance of Ph(-)CAs was 11.1 months (1-28 months). In 7 patients, the Ph(-)CAs have disappeared in 10.9 months (3-24 months). In such patients, no myelodysplastic syndrome or acute leukemia was observed. One patient has progressed to acute monocytic leukemia with Ph(+)cells. All remaining patients have achieved bone morrow remission, among which 11 patients achieved complete cytogenic response and 4 patients even achieved complete molecular response. CONCLUSION: The majority of Ph(-)CAs developed in CML patients are transient in nature. They may develop following imatinib, dasatinib or bosutinib therapy but do not interfere with the therapeutic effects of tyrosine kinase inhibitors.

[Cytogenetic analysis of 154 case of acute myeloid leukemia with t(8;21)].

OBJECTIVE: To investigate the cytogenetic features of acute myeloid leukemia (AML) with t(8;21). METHODS: The clinical characteristics of 154 cases of acute myeloid leukemia with t(8;21) in our hospital were analyzed retrospectively. According to the chromosome karyotype, all cases were divided into three groups: the group without additional chromosome abnormality, the group with single sex chromosome loss and the group with additional chromosome abnormalities other than sex chromosome loss. RESULT: In this study, according to FAB classification, there were 127 cases of M2 (82.5%), 15 of M5 (9.7%), 6 of M4 (3.9%), 4 of M1(2.6%) and 2 of M0(1.3%). Cytogenetically, 85 (55.2%) AML patients with t(8;21) had additional chromosome abnormalities. The most common abnormalities were sex chromosome loss, of which -Y was detected in 44.1% of the male karyotype and X in 27.9%. Beside that, there were 9 cases of 9q- (5.8%), 5 of +8(3.3%),3 of +4(2.0%) and 17 of other chromosome anomalies (11.4%). In the group of t(8;21) with additional chromosome abnormalities, 11 cases (35.5%) were non-M2 AML, higher than that in single t(8;21) group (17.4%)(P<0.05); however, there was no significant difference between the group of single t(8;21) and the group of t(8;21) with single sex chromosome loss(P>0.05). CONCLUSION: t(8;21) translocation is usually accompanied by additional chromosome abnormalities, particularly in M2; while t(8;21) with additional chromosome abnormalities other than sex chromosome loss is more frequently observed in non-M2 AML.

CD19-positive acute myeloblastic leukemia with trisomy 21 as a sole acquired karyotypic abnormality.

We report that a 63-year-old Chinese female had acute myeloblastic leukemia (AML) in which trisomy 21 (+21) was found as the sole acquired karyotypic abnormality. The blasts were positive for myeloperoxidase, and the immunophenotype was positive for cluster of differentiation 19 (CD19), CD33, CD34, and human leukocyte antigens (HLA)-DR. The chromosomal analysis of bone marrow showed 47,XX,+21[2]/46,XX[18]. Fluorescent in situ hybridization (FISH) showed that three copies of AML1 were situated in separate chromosomes, and that t(8;21) was negative. The patient did not have any features of Down syndrome. A diagnosis of CD19-positive AML-M5 was established with trisomy 21 as a sole acquired karyotypic abnormality. The patient did not respond well to chemotherapy and died three months after the diagnosis. This is the first reported case of CD19-positive AML with trisomy 21 as the sole cytogenetic abnormality. The possible prognostic significance of the finding in AML with +21 as the sole acquired karyotypic abnormality was discussed.