Translocation (9;11)(p21;q23) in three cases of acute monoblastic leukemia

A balanced translocation t(9;11)(p21;q23) was found in three cases of acute monoblastic leukemia (AMol or M5 according to the FAB classification). This translocation, which involves small chromosomal segments of approximately the same length, is difficult to recognize with certainty when techniques other than R-bands are used. A new specific association is proposed between this translocation and acute leukemia of the M5 type.     

Infant acute lymphoblastic leukemia with t(11;16)(q23;p13.3) and lineage switch into acute monoblastic leukemia

Rearrangements of the mixed-lineage leukemia (MLL) gene have been associated with a poor prognosis in infant acute lymphoblastic leukemia (ALL). Previously, MLL translocations involving the CREP-binding protein (CREBBP) gene at chromosome band 16p13.3 have primarily been reported in treatment-related acute myeloid leukemia, after chemotherapy for other primary malignancies using topoisomerase II inhibitors. We report a case of de novo infant ALL with t(11;16)(q23;p13.3). After chemotherapy, this patient developed an acute monoblastic leukemia (M5b) with retention of the t(11;16)(q23;p13.3), indicating that this is a lineage switch of the original leukemic clone. To our knowledge, these findings have not been previously reported.     

Translocation (11;16)(q23;p13) acute myelogenous leukemia and myelodysplastic syndrome

The purpose of this study is to examine the relationship of t(11;16)(q23;p13) to the type of myeloproliferative disorder noted by hematopathology. Previously, t(11;16) has been reported in fewer than 20 patients, all with the diagnosis of therapy-related (secondary) acute myelogenous leukemia (sAML) or myelodysplastic syndrome (MDS). Putative involved genes are the MLL on 11q23 and CBP at 16p13. Data from The University of Texas M. D. Anderson Cancer Center (UTMDACC) Cytogenetics Laboratory revealed 3 patients with t(11;16) observed during the past 5 years. Two of the patients had a prior diagnosis of non-Hodgkin lymphoma (NHL) and had been treated with chemotherapy, which included cyclophosphamide. The other patient presented with de novo AML and no history of cancer or chemotherapy. Two of the 3 patients had t(11;16) as the sole cytogenetic abnormality. One patient had a t(11;16) clone that included t(9;21) and t(10;21) as additional changes. Translocation (11;16) has previously been reported only as being therapy-related. In this study, the t(11;16) was seen in 2 patients with previous lymphomas treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). A single patient with apparently de novo AML constitutes the first reported instance of non-treatment associated t(11;16) AML.     

Translocation (8;18;16)(p11;q21;p13). A new variant of t(8;16)(p11;p13) in acute monoblastic leukemia: case report and review of the literature

A complex three-way t(8;18;16)(p11;q21;p13) was detected in a 15-month-old patient with acute myeloid leukemia (AML). The patient had typical clinical manifestation and bone marrow features of AML subtype M5b associated with t(8;16)(p11;p13). Therefore, we believe that the t(8;18;16) is a new variant of t(8;16) related to AML M4/M5. We also review other t(8;16)(p11;p13) variants reported in the literature.     

Pediatric acute myeloid leukemia with t(7;21)(p22;q22)

The t(7;21)(p22;q22) resulting in RUNX1‐USP42 fusion, is a rare but recurrent cytogenetic abnormality associated with acute myeloid leukemia (AML) and myelodysplastic syndromes. The prognostic significance of this translocation has not been well established due to the limited number of patients. Herein, we report three pediatric AML patients with t(7;21)(p22;q22). All three patients presented with pancytopenia or leukopenia at diagnosis, accompanied by abnormal immunophenotypic expression of CD7 and CD56 on leukemic blasts. One patient had t(7;21)(p22;q22) as the sole abnormality, whereas the other two patients had additional numerical and structural aberrations including loss of 5q material. Fluorescence in situ hybridization analysis on interphase cells or sequential examination of metaphases showed the RUNX1 rearrangement and confirmed translocation 7;21. Genomic SNP microarray analysis, performed on DNA extracted from the bone marrow from the patient with isolated t(7;21)(p22;q22), showed a 32.2 Mb copy neutral loss of heterozygosity (cnLOH) within the short arm of chromosome 11. After 2‐4 cycles of chemotherapy, all three patients underwent allogeneic hematopoietic stem cell transplantation (HSCT). One patient died due to complications related to viral reactivation and graft‐versus‐host disease. The other two patients achieved complete remission after HSCT. Our data displayed the accompanying cytogenetic abnormalities including del(5q) and cnLOH of 11p, the frequent pathological features shared with other reported cases, and clinical outcome in pediatric AML patients with t(7;21)(p22;q22). The heterogeneity in AML harboring similar cytogenetic alterations may be attributed to additional uncovered genetic lesions.     

Translocation (Y;1)(q12;q21) in acute leukemia

This report documents one patient with myelodysplasia evolving into acute leukemia who showed a t(Y;1) translocation confirmed by in situ hybridization. Most of the q arm of the Y chromosome was translocated to an additional q arm of chromosome 1, resulting in trisomy 1q. To our knowledge only four other cases with this t(Y;1) have been reported.     

Translocation (11;19)(q23;p13.3) associated with a novel t(5;16) (q13;q22) in a patient with acute myelocytic leukemia

A novel association of t(11;19)(q23;p13) and t(5;16)(q13;q22) was detected by G-banding and spectral karyotyping studies in an 18-year-old patient. While balanced t(11;19) has been often described in acute myelocytic leukemia (AML) French-American-British Cooperative Group subtypes M4 and M5, this patient was diagnosed with the variant AML-M4 with eosinophilia (AML-M4Eo), which is associated with abnormalities in 16q22 and has good prognosis. However, the patient relapsed after allogeneic transplant and died within 2 years of diagnosis, which suggests that the association of these two translocations correlates with a poor prognosis. This report expands the molecular basis of the variability in clinical outcomes and adds the novel t(5;16)(q13;q22) to the spectrum of chromosome 16q22 abnormalities in AML.     

A possible specific chromosome marker for monocytic leukemia: three more patients with t(9;11)(p22;q24) and another with t(11;17)(q24;q21), each with acute monoblastic leukemia

An apparently balanced 9;11 reciprocal translocation with break points most likely at 9p22 and 11q24 was found in 3 patients with acute monocytic leukemia [M5 in the French-American-British (FAB) classification schema]. This translocation was not observed in 6 other patients with M5 acute nonlymphocytic leukemia (ANLL) or in chromosome studies on 143 patients with other types of ANLL. This study supports the previously published suggestion that such 9;11 translocations may be associated with some patients with M5 ANLL. In this report, we have also included a patient with M5 ANLL who had an 11;17 translocation with break points apparently at 11q24 and 17q21. Perhaps this is a variant translocation of chromosome No. 11, which may also be associated with monocytic leukemia.     

Translocation (9;11)(p21;q23) in a case of acute myeloblastic leukemia (AML-M2)

A patient with acute myeloblastic leukemia (AML-M2) and a balanced translocation, t(9;11)(p21;q23), is described. The translocation appears to be the same as that previously reported in some patients with acute monoblastic leukemia (AMoL-M5). This suggests that, although t(9;11)(p21;q23) frequently may be associated with AMoL, the translocation may not be specific for that disorder.     

5例伴有t(16;21)(p11;q22)急性白血病的临床和实验研究

目的：报告5例伴有t(16;21)(p11;q22)的急性白血病和其中1例的染色体涂染分析。方法：骨髓细胞24h培养后按常规方法制备染色体，采用R显带技术进行染色体核型分析，并以16号和21号整条染色体涂染探针对其中1例患者进行染色体涂染检测。结果：5例均显示t(16;21)(p11;q22),占15年来进行染色体检查的急性非淋巴细胞白血病患者总数的0．3％（5／1448）。5例均无白血病细胞吞噬其他血细胞现象。1例患者的染色体涂染分析证实了16号和21号染色体之间发生了相互易位。结论：t(16;21)是急性非淋巴细胞白血病中1种少见的非随机的染色体易位，代表了1种独特的白血病亚型。染色体涂染技术是比常规核型分析更为可靠的检测该易位的手段。     

Translocation (3;6)(q21;p21) in acute myeloid leukemia with abnormal thrombopoiesis and basophilia

A case of acute myeloid leukemia (AML) with increased numbers of basophils and abnormal megakaryocytes was shown to have a t(3;6)(q21;p21) in the bone marrow cells. The morphology is described in detail and the case is discussed with reference to t(6;9)(p23;q34) and inv/ins(3)(q21q26) in AML. It is possible that increased numbers of basophils in AML may be associated with a translocation involving 6p21-6p23.     

Novel chromosome 16 abnormality--der(16)del(16) (q13)t(16;21)(p11.2;q22)--associated with acute myeloid leukemia.

Inversion of chromosome 16 is a common feature of acute myeloid leukemia (AML) M4, while t(16;21), although also associated with AML, appears to be a separate entity. We present a patient with myelodysplastic syndrome (MDS) who transformed to AML-M1. The karyotype was normal at diagnosis; at 15 months, hematological evidence of transformation was present, and repeat cytogenetics showed a novel rearrangement of one chromosome 16. Two breaks had occurred; one in the short arm at 16p11, with translocation of the segment distal to this onto chromosome 21q, and the other in the long arm at 16q22 with subsequent deletion of the segment from 16q22-->qter. Fluorescence in situ hybridization (FISH) confirmed the abnormalities detected by cytogenetics and excluded involvement of the AML1 gene on 21q22. While the 16q22 breakpoint was at the usual site for the inv(16), the 16p11 was not. The patient is more characteristic of t(16;21) than inv(16), and adds to the spectrum of chromosome 16 abnormalities in AML.     

Translocation (1;3)(p36;q21) in secondary leukemia

A case of acute nonlymphocytic leukemia (M4) secondary to treatment for multiple myeloma is described. The patient presented a translocation t(1;3)(p36;q21) and monosomy 7.     

t(9;11)(p22;q24) in a patient with acute monocytic leukemia

A case of t(9;11)(p22;q24) in a patient with acute monocytic leukemia is described. The difficulties of establishing the precise breakpoints involved in this emerging association are discussed.