RUNX1 amplification in lineage conversion of childhood B-cell acute lymphoblastic leukemia to acute myelogenous leukemia

Amplification of RUNX1 (alias AML1) is a recurrent karyotypic abnormality in childhood acute lymphoblastic leukemia (ALL) that is generally associated with a poor outcome. It does not occur with other primary chromosomal abnormalities in acute ALL. AML1 amplification in acute myelogenous leukemia (AML) is a rare secondary event described mainly in therapy-related cases. AML1 amplification was found in a 13-year-old patient with AML M4/M5 leukemia that occurred 5 years after she had been diagnosed with common B-cell ALL. Conventional cytogenetic, fluorescent in situ hybridization (FISH), and polymerase chain reaction methods revealed no other chromosomal change expected to occur in a disease that we assumed to be a secondary leukemia. Due to the lack of cytogenetic data from the diagnostic sample, we developed a new approach to analyze the archived bone marrow smear, which had been stained previously with May-Grünwald-Geimsa by the FISH method. This analysis confirmed that in addition to t(12;21), AML1 amplification and overexpression existed already at the time the diagnosis was made. The chromosomal changes, however, were found in different clones of bone marrow cells. While the first course of chemotherapy successfully eradicated the cell line with the t(12;21), the second cell line with AML1 amplification remained latent during the time of complete remission and reappeared with a different immunophenotype.     

Acute myeloid leukemia in children treated with epipodophyllotoxins for acute lymphoblastic leukemia

BACKGROUND AND METHODS. Treatment of cancer with the epipodophyllotoxins (etoposide and teniposide) has been linked to the development of acute myeloid leukemia (AML) in children and adults, but the factors that might influence the risk of this complication of therapy are poorly defined. We therefore assessed the importance of potential risk factors for secondary AML in 734 consecutive children with acute lymphoblastic leukemia who attained complete remission and received continuation (maintenance) treatment according to different schedules of epipodophyllotoxin administration. RESULTS. Secondary AML was diagnosed in 21 of the 734 patients, in 17 of whom this complication was the initial adverse event. Prolonged administration of epipodophyllotoxin (teniposide with or without etoposide) twice weekly or weekly was independently associated with the development of secondary AML (P less than 0.01 by Cox regression analysis). The overall cumulative risk of AML at six years was 3.8 percent (95 percent confidence interval, 2.3 percent to 6.1 percent); but within the subgroups treated twice weekly or weekly, the risks were 12.3 percent (95 percent confidence interval, 5.7 percent to 25.4 percent) and 12.4 percent (95 percent confidence interval, 6.1 percent to 24.4 percent), respectively. In the subgroups not treated with epipodophyllotoxins or treated with them only during remission induction or every two weeks during continuation treatment, the highest cumulative risk was 1.6 percent (95 percent confidence interval, 0.4 percent to 6.1 percent). After adjustment for treatment frequency, there was no apparent relation between the total dose of epipodophyllotoxins and the development of secondary AML. The relative hazard of etoposide as compared with teniposide could not be determined. CONCLUSIONS. The risk of epipodophyllotoxin-related AML depends largely on the schedule of drug administration. Other factors, including the cumulative dose of epipodophyllotoxin, radiotherapy, and the initial biologic features of the leukemic blast cells, do not appear to have critical roles.     

DNA aneuploidy in adult acute leukemia

Using flow cytometric techniques, we determined DNA ploidy levels in the bone marrow of 318 successive adult patients with newly diagnosed acute leukemia. Overall, 26% exhibited DNA stem line abnormalities, usually with a 10%-15% DNA excess, regardless of morphologic diagnosis. DNA aneuploidy was seen most frequently in patients with a hyperdiploid chromosome number and karyotype instability (50%), but was also present in a third of patients with chromosomal translocations and in 20% of patients with a normal diploid karyotype. Thus, among 73 patients with DNA aneuploidy, quantitatively concordant karyotype abnormalities were observed in almost 40% of patients; the discrepancy between DNA content and chromosome number in the remaining patients may reflect differences in the cell cycle position of target cells in G1/0 phase or mitosis, respectively. Cytogenetics affected treatment outcome in acute myelogenous leukemia (AML) with more favorable short- and long-term prognosis among patients with translocations compared with those with numeric abnormalities. The presence of an abnormal DNA stem line, among AML patients with translocations, identified a favorable subgroup with significantly longer remission duration and survival (25 and 26 months versus 18 and 13 months, respectively). In addition, the prognostic implications of DNA aneuploidy in AML were age-dependent, in that favorable effects among patients with translocations and unfavorable effects among those with numeric abnormalities or diploid karyotypes were most obvious in young and not in older patients (greater than or equal to 40 years). In adults with ALL, DNA aneuploidy was associated with shorter survival (15 versus 39 months in the diploid group), an observation that is distinctly at variance with recent findings in childhood ALL. Our results indicated that DNA flow cytometry was complementary to standard cytogenetics for the detection of genomic abnormalities; and DNA aneuploidy emerged, like in children but not in adults with ALL, as a new favorable prognostic feature in a subgroup of adults with AML, the biologic basis of which remains to be determined.     

Allogeneic bone marrow transplantation after hyperfractionated total-body irradiation and cyclophosphamide in children with acute leukemia

Ninety-seven children with either acute lymphoblastic leukemia (ALL) or acute myelogenous leukemia (AML) received HLA-identical bone marrow transplants from sibling donors, after preparation with 1320 cGy of hyperfractionated total-body irradiation and high-dose cyclophosphamide. Kaplan-Meier product-limit estimates (means +/- SE) of disease-free survival at five years among patients with ALL in second remission, third remission, and fourth remission or relapse were 64 +/- 9, 42 +/- 14, and 23 +/- 11 percent, respectively, with probabilities of relapse of 13 +/- 7, 25 +/- 13, and 64 +/- 16 percent. Among patients with AML in first remission, second remission, and third remission or relapse, five-year disease-free survival estimates were 66 +/- 10, 75 +/- 15, and 33 +/- 19 percent, with respective relapse probabilities of 0, 13 +/- 12, and 67 +/- 19 percent. The most frequent cause of death in patients in early remission (ALL in second or third remission or AML in first or second remission) was bacterial sepsis, fungal sepsis, or both, most often in the presence of acute or chronic graft-versus-host disease. Among patients with ALL who received transplants while in second remission, the duration of the initial remission had no effect on the probability of relapse after transplantation. The only pretransplantation factor that significantly affected outcome was the disease status at the time of transplantation; patients in early remission had better disease-free survival. We conclude that transplantation after preparation with hyperfractionated total-body irradiation and cyclophosphamide is an effective mode of therapy in children with refractory forms of acute leukemia.     

Cytogenetic study of acute lymphoblastic leukemia and its correlation with immunophenotype and genotype.

Among 72 Chinese patients with acute lymphoblastic leukemia (ALL), 50 had clonal chromosomal abnormalities. Structural abnormalities were detected in 42 patients: these included t(9;22) in 9, t(1;19) in 6, t(4;11) in 5, del(11)(q23) in 4, and del(6q) in 4. Adults had a higher incidence of t(9;22) and t(1;19) but a lower incidence of t(4;11) and hyperdiploid greater than 50 karyotype than children. A significant difference was also noted in white blood cell (WBC) count among various karyotypic groups. Patients with chromosomal abnormalities t(9;22), t(1;19), t(4;11) and del(11) (q23) had a shorter complete remission duration as compared with patients free of these abnormalities. Immunophenotyping was performed on 69 patients. All patients with t(9;22), t(1;19), and t(4;11) had B-lineage ALL restricted to certain stages of maturation: groups III and IV, groups IV and V, and group II, respectively (according to the classification of Foon and Tood). Among patients with t(9;22), t(4;11), and del(11)(q23), which have been considered to be associated with acute mixed-lineage leukemia, one each, respectively, showed myeloid antigen expression on the leukemic blasts (My+ ALL). No cross-lineage rearrangements of immunoglobulin (Ig) or T-cell receptor (TCR) genes were detected in these karyotypic subgroups of patients who underwent gene analysis.     

Acute lymphoblastic leukemia. Survey of immunophenotype, French-American-British classification, frequency of myeloid antigen expression, and karyotypic abnormalities in 210 pediatric and adult cases

Immunophenotypic studies are essential to distinguish acute lymphoblastic leukemia (ALL) from minimally differentiated acute myeloid leukemia (AMLM0) and to classify ALL into immunologic subtypes. Frequently, immunophenotyping identifies myeloid antigen expression in ALL, causing a potential diagnostic problem. To evaluate the immunophenotype of ALL, we studied 210 cases of pediatric and adult ALL by flow cytometry and compared the results with the French-American-British (FAB) Cooperative Group classification and the karyotypic findings. Myeloid-associated antigens were expressed in 78 (45.6%) of precursor B-cell ALL cases. Pediatric precursor B ALLs had a higher frequency of myeloid antigen expression than did adult cases. All mature B-cell ALL cases were negative for TdT and myeloid antigens. Myeloid antigen expression was less frequent in T-cell ALL cases compared with precursor B-cell ALL cases. Of the 192 cases submitted for cytogenetic analysis, 147 were abnormal. The most common chromosomal translocation was the Philadelphia chromosome, which was more likely to have L2 blast morphology and a precursor B immunophenotype. Myeloid antigen expression was present in 70.8% of Ph-positive cases (P = .008). Chromosome rearrangements involving 11q23 also showed an increased frequency of myeloid antigen expression. Chromosome translocations involving regions of T-cell receptor genes were present in 24% of T-cell ALL cases. A high percentage of ALL cases, however, had various other cytogenetic abnormalities, many of which involved less well-studied chromosomal regions.     

Amplification of the 11q23 region in acute myeloid leukemia.

Cytogenetic abnormalities involving the 11q23 region are found in both acute lymphoblastic leukemia (ALL) and myeloid leukemia (AML). Molecular consequences of 11q23 translocations are the formation of chimeric genes, all of them involving the MLL (mixed-lineage leukemia) gene. To evaluate the usefulness of fluorescence in situ hybridization (FISH) in detecting MLL rearrangements in AML, we analyzed 181 patients with an MLL-specific probe. Among them, we detected three patients with multiple FISH signals, reflecting genomic amplification of this chromosomal region. Extra copies of MLL have been reported previously in four patients, but did not correspond to a true gene amplification. For the first time, we describe genomic amplification of the 11q23 region (up to more than 50 copies) in AML patients. This genomic amplification could affect MLL, but other genes in the vicinity could also be the primary target. Genes Chromosomes Cancer 26:166-170, 1999.     

MLL-CBP fusion transcript in a therapy-related acute myeloid leukemia with the t(11;16)(q23;p13) which developed in an acute lymphoblastic leukemia patient with Fanconi anemia

We describe a boy with Fanconi anemia (FA) who developed acute lymphoblastic leukemia (ALL) (FAB-LI) followed by acute myeloid leukemia (AML) (FAB-M5) at relapse. The patient was diagnosed with early pre-B-cell ALL without preceding aplastic anemia and was treated with ALL-oriented chemotherapy which included doxorubicin (a total dose of 140 mg/m(2) administered), which is a topoisomerase II inhibitor. Complete remission was obtained, but after 38 weeks AML developed. The karyotype of ALL cells at diagnosis showed 46,XY, and that of AML cells at relapse was 46,XY, t(11;16)(q23;p13). An MLL gene rearrangement and MLL-CBP chimeric mRNA were found in AML, but not in ALL. A diagnosis of FA was confirmed by an increased number of chromosomal breaks and rearrangements in peripheral blood lymphocytes cultured with mitogen in the presence of mitomycin C. We conclude that this FA patient developed ALL followed by a therapy-related t(11;16)-AML resulting in an MLL-CBP fusion. Further examination of such patients would shed light on leukemogenesis in FA patients. Genes Chromosomes Cancer 27:264-269, 2000.     

Loss or downregulation of HLA class I expression at the allelic level in acute leukemia is infrequent but functionally relevant, and can be restored by interferon

Human leukocyte antigen (HLA) class I expression at the allelic level was analyzed in 397 acute myeloid leukemia (AML) and 186 acute lymphoid leukemia (ALL) using a complement-dependent cytotoxicity assay. Impaired recognition possibly due to HLA downregulation was observed in 2% of the patients with AML and ALL in complete remission, and in 8%-15% in the groups with blasts. In 15 instances of diminished cytotoxicity, leukemic cells and control PHA blasts from the same patients were further analyzed using flow cytometry. In 4/6 ALL and 4/9 AML patients HLA downregulation or complete loss (2 patients) of cell surface expression could be confirmed. No genomic abnormalities were observed. In addition, 12 AML and 13 ALL patients were tested during relapse using flow cytometry. In 1/12 AML patients and 1/13 ALL patients allelic downregulation of cell surface expression was found. In two patients tested, downregulation or loss of cell surface expression of HLA class I antigens corresponded with impaired T cell mediated lysis by HLA restricted cytotoxic T lymphocyte.Treatment of the cells with alpha- or gamma-interferon could restore HLA class I expression and T-cell recognition. In conclusion, downregulation of cell surface expression of HLA class I expression at the allelic level in AML and ALL is infrequent but functionally relevant. HLA downregulation was reversible and T-cell recognition could be restored by alpha- or gamma-interferon.     

Long-term survival in acute leukemia. Twenty-two adult patients surviving for over five years

An intermittent combination chemotherapy program was initiated in 1971-79 in 172 patients, aged 15-59 years, with acute leukemia (131 myelogenous (AML) and 41 lymphoblastic (ALL]. Sixteen patients with AML and 6 with ALL have survived for more than 5 years. These long-term survivors represent 24% of AML and 18% of ALL patients who obtained complete remission. Twelve patients (10 AML and 2 ALL) are in continuous first remission 5.5-13.5 years after diagnosis. Occasional late relapses up to 9 years after diagnosis make it impossible to declare any individual patient cured.     

CD64在急性白血病免疫分型中的意义

目的探讨CD64在急性白血病免疫分型中的意义。方法应用直接荧光标记法,经流式细胞术对116例急性髓系白血病(AML)和70例急性淋巴细胞白血病(ALL)进行免疫表型的检测。结果 AML组CD64的表达阳性率明显高于ALL组(41.4%vs 2.9%,P<0.01)。CD64在M5和M4的表达阳性率最高,分别为77.1%和55.6%。CD64的阳性表达率在M0(0)、M1(0)、M2(7.9%)明显低于M3(47.1%)、M4与M5(P<0.01)。各亚型CD64阳性病例中,M4、M5的CD64阳性细胞表达率分别为(62.5±24.7)%、(68.7±25.9)%,均明显高于M2(28.3%±5.7%)、M3(34.3%±6.3%)(P<0.01)。CD64对诊断AML的灵敏度优于CD14,其特异度优于CD117、CD33及CD13。虽然CD64诊断M4\M5的特异度较CD14稍差(82.5%vs 100%),但是灵敏度高于CD14(69.8%vs 41.5%)。结论 CD64可作为辅助诊断AML的髓系标志抗原,有助于提高M4/M5的检出率及其与其他AML亚型的鉴别诊断。     

Nonrandom cytogenetic changes in New Zealand patients with acute myeloid leukemia

Bone marrow clones with abnormal chromosomes were observed in 56% of 66 patients with forms of acute myeloid leukemia [French-American-British (FAB) M1-M6]. Acute myeloblastic leukemia (AML, M1 and M2) was the most common form, and 65% of these patients showed chromosomal abnormalities compared with 41% of patients with acute myelomonocytic leukemia (AMMoL, M4). The recognized nonrandom chromosomal abnormalities found were trisomy 8, monosomy 5 or 7, trisomy 1q, t(6;9), t(8;21), t(15;17), and abnormalities in 17q. There was also a strong involvement of chromosome No. 11: Abnormalities were found in eight patients when their leukemia was diagnosed and in a further three patients during the course of karyotypic evolution. Six of these patients had AMMoL or AMoL. Complex or multiple clones were found in 37% of AML patients at diagnosis. Our AML patients had a reduced frequency of abnormalities in chromosome No. 5 or 7 and an increased frequency of abnormalities in chromosome No. 8 compared with studies reported in other countries (p = 0.01). This difference suggests that in New Zealand AML might be caused by factors different from those operating in more industrialized centers.     

Cytogenetic abnormalities during clinical, immunophenotypic, and molecular remission in pediatric acute lymphoblastic leukemia

The significance of random cytogenetic abnormalities detected in pediatric acute lymphoblastic leukemia (ALL) during remission is unknown. We studied 10 of 72 consecutive ALL patients who developed cytogenetic abnormalities during clinical remission to determine their effect on remission status. The cytogenetic abnormalities occurred at a median of 14.5 months (range 5-72) from the initial diagnosis. Five abnormalities were designated as clonal (monosomy 21 in three metaphases and 64 approximately 69,XXY in three metaphases from one patient at different times, and del(20)(q12q13) in three metaphases, add(13)(q34) in two metaphases, and ?del(19)(p11) in two metaphases from three different patients). Seven abnormalities were previously described: del(5)(q12), del(5)(q33), -7, del(11)(q23), +12, and +13 each in one metaphase, and del(20)(q12q13) in three metaphases). The remaining cytogenetic abnormalities were nonclonal and random. Flow cytometry and analysis of IgH and TcR gene rearrangements showed that all evaluable patients were in immunophenotypic and molecular remission, respectively. Eight patients remain in clinical and molecular remission a median of 9 months (range 7-18) after detecting the cytogenetic abnormality, and the leukemia in two patients has relapsed. During remission, cytogenetic abnormalities may not be a harbinger of leukemia relapse in pediatric ALL; therefore, a wait-and-see approach is prudent.     

The proportion of abnormal karyotypes in acute leukemia samples related to method of preparation

Bone marrow and peripheral blood were studied from 200 patients with acute leukemia [109 with acute myeloid leukemia (AML), 91 with acute lymphoblastic leukemia (ALL)] who had samples cultured for varying times and who had a mixture of chromosomally abnormal and normal cells. The mean percentage of abnormal metaphase cells increased with culture time. The peak was reached at 48 hours and declined slightly after 72 hours in culture for ALL patients. The mean percentage of abnormal cells increased up to 72 hours in culture for AML patients. In 68 patients (31 AML and 37 ALL), cytogenetic data were available from samples processed with both direct preparations and culture methods. The percentage of abnormal cells increased after culture in 49 patients (23 AML and 26 ALL), while it decreased or remained at the same level in 19 patients. For AML patients, the mean percentage of abnormal cells was significantly different between direct (38%) and cultured preparations (63%), (p less than 0.001). Seven of 9 patients with AML who showed a greater than 50% increase in abnormal cells after culture had either a t(8;21), t(15;17), or abnormalities involving 11q23. The two patients who showed a significant decrease in abnormal cells both had a translocation involving 11q13. Compared with ALL, more AML patients showed greater than 80% abnormal bone marrow metaphase cells at diagnosis or at relapse.     

Cytogenetic studies of 44 T-cell acute lymphoblastic leukemias

Cytogenetic studies on 44 patients with T-cell acute lymphoblastic leukemia (ALL) were reported. The incidence of leukemia without detectable chromosomal changes was 25%. Hyperdiploidy with more than 50 chromosomes was found in only one patient. Previously described nonrandom abnormalities like 6q-, 9p-, and 12p- were observed, and it was confirmed that they are not specific for a particular type of ALL. The incidence of chromosomal rearrangements on chromosomes 7 and 14 where the T-cell receptor gene loci are located was 36% of those with abnormal karyotypes and 27% of the total. This was clearly different from the frequency of rearrangements of these bands found in T-cell lymphoma. Finally, a rearrangement on bands 11q14-q21 was detected in five cases.     

Pediatric T-cell acute lymphoblastic leukemia with aberrations of both MLL loci

Translocations involving the MLL gene at 11q23 have been implicated in acute lymphoblastic leukemia (ALL), as well as acute myeloid leukemia (AML). Such translocations result in gain of function fusion proteins that drive cell proliferation. Except in cases of T-cell ALL, MLL rearrangement is typically associated with a poor prognosis. We report a case of T-cell ALL with a t(11;19)(q23;p13.3) and deletion of the other chromosome 11 homolog at band q23. Fluorescence in situ hybridization (FISH) analyses confirmed involvement of the MLL loci in both the translocation and deletion. This case is unique in that deletions of 11q23 reported in ALL generally do not involve MLL. We are unaware of a previous report showing rearrangement of the MLL loci on both chromosome 11 homologues.     

Frequent deletions at 12q14.3 chromosomal locus in adult acute lymphoblastic leukemia

Cytogenetic abnormalities at the 12q12-q14 chromosomal locus are rarely detected in acute lymphoblastic leukemia (ALL). To examine submicroscopic deletions at this locus, we analyzed 78 adult precursor B- and T-cell ALL cases [27 with Philadelphia chromosome (Ph)-negative B-cell ALL, 20 with Ph-negative B-cell ALL with expression of one or two myeloid markers, 18 with Ph-positive B-cell ALL, and 13 with T-cell ALL] using a panel of 13 microsatellite (MST) markers that span the 12q12-q14.3 region. The status of MST markers was evaluated by use of polymerase chain reaction performed with fluorescence-labeled primers and automated fragment analysis. The MST marker analyses showed submicroscopic deletions at the 12q14.3 locus in 20 of the 78 ALL cases (26%). The frequency of deletions was highest in Ph-negative B-cell ALL (13 of 27, 48%) compared with that in Ph-negative B-cell ALL with expression of myeloid markers (4 of 20, 20%), Ph-positive B-cell ALL (2 of 18, 11%), and T-cell ALL (1 of 13, 8%). Deletion frequencies of MST markers along the 12q12-q14.3 locus suggest that the targeted gene of deletion is located within a 170-kb region bordered by the markers D12S1504 (approximately 65 kb upstream of HMGA2) and D12S1509 (in intron 3 of HMGA2) at the 12q14.3 locus. These submicroscopic deletions at the 12q14.3 locus may play a role in the pathogenesis of ALL, particularly in Ph-negative precursor B-cell ALL.     

A t(4;11)(q21;p15) in a case of T-cell lymphoma and a case of acute myelogenous leukemia

The translocation (4;11)(q21;p15) has been observed in acute lymphoblastic as well as acute myeloid leukemias (ALL and AML, respectively). We report the first case of T-cell lymphoma with t(4;11)(q21;p15) and a case of AML. The clinical history of and cytogenetics in the latter is suggestive of a secondary leukemia; his karyotype revealed emergence of a t(3;11)(q21;q13) in addition to the t(4;11). Previously reported cases with t(4;11)(q21;p15) are reviewed, clinical and morphological characteristics of cases with t(4;11)(q21;q23) and t(4;11)(q21;p15) are compared, and chromosome abnormalities involving the NUP98 gene in hematologic malignant disorders are reviewed.