Wen-Chien Chou

Multicenter, Randomized, Open-Label, Phase III Trial of Decitabine Versus Patient Choice, With Physician Advice, of Either Supportive Care or Low-Dose Cytarabine for the Treatment of Older Patients With Newly Diagnosed Acute Myeloid Leukemia

PURPOSE This multicenter, randomized, open-label, phase III trial compared the efficacy and safety of decitabine with treatment choice (TC) in older patients with newly diagnosed acute myeloid leukemia (AML) and poor- or intermediate-risk cytogenetics. PATIENTS AND METHODS Patients (N = 485) age ≥ 65 years were randomly assigned 1:1 to receive decitabine 20 mg/m(2) per day as a 1-hour intravenous infusion for five consecutive days every 4 weeks or TC (supportive care or cytarabine 20 mg/m(2) per day as a subcutaneous injection for 10 consecutive days every 4 weeks). The primary end point was overall survival (OS); the secondary end point was the complete remission (CR) rate plus the CR rate without platelet recovery (CRp). Adverse events (AEs) were recorded. RESULTS The primary analysis with 396 deaths (81.6%) showed a nonsignificant increase in median OS with decitabine (7.7 months; 95% CI, 6.2 to 9.2) versus TC (5.0 months; 95% CI, 4.3 to 6.3; P = .108; hazard ratio [HR], 0.85; 95% CI, 0.69 to 1.04). An unplanned analysis with 446 deaths (92%) indicated the same median OS (HR, 0.82; 95% CI, 0.68 to 0.99; nominal P = .037). The CR rate plus CRp was 17.8% with decitabine versus 7.8% with TC (odds ratio, 2.5; 95% CI, 1.4 to 4.8; P = .001). AEs were similar for decitabine and cytarabine, although patients received a median of four cycles of decitabine versus two cycles of TC. The most common drug-related AEs with decitabine were thrombocytopenia (27%) and neutropenia (24%). CONCLUSION In older patients with AML, decitabine improved response rates compared with standard therapies without major differences in safety. An unplanned survival analysis showed a benefit for decitabine, which was not observed at the time of the primary analysis.

AML1/RUNX1 Mutations in 470 Adult Patients with De Novo Acute Myeloid Leukemia: Prognostic Implication and Interaction with Other Gene Alterations.

Somatic mutation of the AML1/RUNX1(RUNX1) gene is seen in acute myeloid leukemia (AML) M0 subtype and in AML transformed from myelodysplastic syndrome, but the impact of this gene mutation on survival in AML patients remains unclear. In this study, we sought to determine the clinical implications of RUNX1 mutations in 470 adult patients with de novo non-M3 AML. Sixty-three distinct RUNX1 mutations were identified in 62 persons (13.2%); 32 were in N-terminal and 31, C-terminal. The RUNX1 mutation was closely associated with male sex, older age, lower lactic dehydrogenase value, French-American-British M0/M1 subtypes, and expression of HLA-DR and CD34, but inversely correlated with CD33, CD15, CD19, and CD56 expression. Furthermore, the mutation was positively associated with MLL/PTD but negatively associated with CEBPA and NPM1 mutations. AML patients with RUNX1 mutations had a significantly lower complete remission rate and shorter disease-free and overall survival than those without the mutation. Multivariate analysis demonstrated that RUNX1 mutation was an independent poor prognostic factor for overall survival. Sequential analysis in 133 patients revealed that none acquired novel RUNX1 mutations during clinical courses. Our findings provide evidence that RUNX1 mutations are associated with distinct biologic and clinical characteristics and poor prognosis in patients with de novo AML.

Distinct clinical and biologic characteristics in adult acute myeloid leukemia bearing the isocitrate dehydrogenase 1 mutation

Mutations of nicotinamide adenine dinucleotide phosphate-dependent isocitrate dehydrogenase gene (IDH1) have been identified in patients with gliomas. Recent genome-wide screening also revealed IDH1 mutation as a recurrent event in acute myeloid leukemia (AML), but its clinical implications in AML are largely unknown. We analyzed 493 adult Chinese AML patients in Taiwan and found 27 patients (5.5%) harboring this mutation. IDH1 mutation was strongly associated with normal karyotype (8.4%, P = .002), isolated monosomy 8 (P = .043), NPM1 mutation (P < .001), and French-American-British M1 subtype (P < .001), but inversely associated with French-American-British M4 subtype (P = .030) and expression of HLA-DR, CD13, and CD14 (P = .002, .003, and .038, respectively). There was no impact of this mutation on patient survival. Sequential analysis of IDH1 mutation was performed in 130 patients during follow-ups. None of the 112 patients without IDH1 mutation at diagnosis acquired this mutation at relapse. In all 18 IDH1-mutated patients studied, the mutation disappeared in complete remission; the same mutation reappeared in all 11 samples obtained at relapse. We conclude that IDH1 is associated with distinct clinical and biologic characteristics and seems to be very stable during disease evolution.

TET2 mutation is an unfavorable prognostic factor in acute myeloid leukemia patients with intermediate-risk cytogenetics.

The studies concerning clinical implications of TET2 mutation in patients with primary acute myeloid leukemia (AML) are scarce. We analyzed TET2 mutation in 486 adult patients with primary AML. TET2 mutation occurred in 13.2% of our patients and was closely associated with older age, higher white blood cell and blast counts, lower platelet numbers, normal karyotype, intermediate-risk cytogenetics, isolated trisomy 8, NPM1 mutation, and ASXL1 mutation but mutually exclusive with IDH mutation. TET2 mutation is an unfavorable prognostic factor in patients with intermediate-risk cytogenetics, and its negative impact was further enhanced when the mutation was combined with FLT3-ITD, NPM1-wild, or unfavorable genotypes (other than NPM1(+)/FLT3-ITD(-) or CEBPA(+)). A scoring system integrating TET2 mutation with FLT3-ITD, NPM1, and CEBPA mutations could well separate AML patients with intermediate-risk cytogenetics into 4 groups with different prognoses (P < .0001). Sequential analysis revealed that TET2 mutation detected at diagnosis was frequently lost at relapse; rarely, the mutation was acquired at relapse in those without TET2 mutation at diagnosis. In conclusion, TET2 mutation is associated with poor prognosis in AML patients with intermediate-risk cytogenetics, especially when it is combined with other adverse molecular markers. TET2 mutation appeared to be unstable during disease evolution.

Nucleophosmin mutations in De novo acute myeloid leukemia : The age-dependent incidences and the stability during disease evolution

Nucleophosmin (NPM) mutations have been found in a significant proportion of adults with de novo acute myeloid leukemia (AML), especially in those of a normal karyotype. These results provide a basis for studies of the pathogenesis in this specific subgroup of AML. In this study, NPM mutations were analyzed in 173 Chinese patients of de novo AML, including adults and children. We found that NPM mutations were present in 19.1% of the overall population and 40.3% of those with a normal karyotype. Adults had a significantly higher incidence of NPM mutations than children [32 of 126 (25.4%) versus 1 of 47 (2.1%), P < 0.001]. NPM mutations were closely associated with normal karyotype (P < 0.001) and internal tandem duplication of FLT3 (P = 0.002), but negatively associated with CEBPA mutations (P = 0.032) and expression of CD34 (P < 0.001) and HLA-DR (P = 0.003). Serial analyses of NPM mutations showed the mutation disappeared at complete remission, but the same mutation reappeared at relapse, except for one who lost the mutation at the second relapse, when new cytogenetic abnormalities emerged. None acquired novel mutations during the follow-up period. In conclusion, NPM mutations occur in an age-dependent fashion. Moreover, the findings that NPM mutations are stable during disease evolution and closely associated with disease status make it a potential marker for monitoring minimal residual disease.

Distinct clinical and biological features of de novo acute myeloid leukemia with additional sex comb-like 1 (ASXL1) mutations

Mutations in the additional sex comb-like 1 (ASXL1) gene were recently shown in various myeloid malignancies, but they have not been comprehensively investigated in acute myeloid leukemia (AML). In this study, we analyzed ASXL1 mutations in exon 12 in 501 adults with de novo AML. ASXL1 mutations were detected in 54 patients (10.8%), 8.9% among those with normal karyotype and 12.9% among those with abnormal cytogenetics. The mutation was closely associated with older age, male sex, isolated trisomy 8, RUNX1 mutation, and expression of human leukocyte antigen-DR and CD34, but inversely associated with t(15;17), complex cytogenetics, FLT3-internal tandem duplication, NPM1 mutations, WT1 mutations, and expression of CD33 and CD15. Patients with ASXL1 mutations had a shorter overall survival than patients without, but the mutation was not an independent adverse prognostic factor in multivariate analysis. Sequential analyses showed that the original ASXL1 mutations were lost at relapse and/or refractory status in 2 of the 6 relapsed ASXL1-mutated patients studied, whereas 2 of the 109 ASXL1-wild patients acquired a novel ASXL1 mutation at relapse. In conclusion, AML bearing ASXL1 mutations showed distinct clinical and biological features. The ASXL1 mutation status can change during disease evolution in a few patients.

DNMT3A mutations in acute myeloid leukemia: stability during disease evolution and clinical implications

DNMT3A mutations are associated with poor prognosis in acute myeloid leukemia (AML), but the stability of this mutation during the clinical course remains unclear. In the present study of 500 patients with de novo AML, DNMT3A mutations were identified in 14% of total patients and in 22.9% of AML patients with normal karyotype. DNMT3A mutations were positively associated with older age, higher WBC and platelet counts, intermediate-risk and normal cytogenetics, FLT3 internal tandem duplication, and NPM1, PTPN11, and IDH2 mutations, but were negatively associated with CEBPA mutations. Multivariate analysis demonstrated that the DNMT3A mutation was an independent poor prognostic factor for overall survival and relapse-free survival in total patients and also in normokaryotype group. A scoring system incorporating the DNMT3A mutation and 8 other prognostic factors, including age, WBC count, cytogenetics, and gene mutations, into survival analysis was very useful in stratifying AML patients into different prognostic groups (P < .001). Sequential study of 138 patients during the clinical course showed that DNMT3A mutations were stable during AML evolution. In conclusion, DNMT3A mutations are associated with distinct clinical and biologic features and poor prognosis in de novo AML patients. Furthermore, the DNMT3A mutation may be a potential biomarker for monitoring of minimal residual disease.

Acute and chronic arsenic poisoning associated with treatment of acute promyelocytic leukaemia

Seven relapsed and/or refractory acute promyelocytic leukaemia patients were treated by arsenic trioxide (As2O3). Four patients (4/7, 57%) achieved complete remission after one to three cycles of treatment and the most common acute side‐effect was fluid retention (in six patients, 86%), including weight gains and pleuro‐pericardial effusions. Evident polyneuropathy compatible with chronic arsenic toxicity was noted in two of the three patients who received As2O3 maintenance therapy and one of them had marked distal muscular atrophy. We suggest that As2O3 may be a useful salvage therapy for relapsed and refractory APL patients, but the acute or chronic arsenic toxicity should be carefully monitored.

WT1 mutation in 470 adult patients with acute myeloid leukemia: stability during disease evolution and implication of its incorporation into a survival scoring system

The impact of WT1 mutations in acute myeloid leukemia (AML) is not completely settled. We aimed to determine the clinical implication of WT1 mutation in 470 de novo non-M3 AML patients and its stability during the clinical course. WT1 mutations were identified in 6.8% of total patients and 8.3% of younger patients with normal karyotype (CN-AML). The WT1 mutation was closely associated with younger age (P < .001), French-American-British M6 subtype (P = .006), and t(7;11)(p15;p15) (P = .003). Multivariate analysis demonstrated that the WT1 mutation was an independent poor prognostic factor for overall survival and relapse-free survival among total patients and the CN-AML group. A scoring system incorporating WT1 mutation, NPM1/FLT3-ITD, CEBPA mutations, and age into survival analysis proved to be very useful to stratify CN-AML patients into different prognostic groups (P < .001). Sequential analyses were performed on 133 patients. WT1 mutations disappeared at complete remission in all WT1-mutated patients studied. At relapse, 3 of the 16 WT1-mutated patients who had paired samples lost the mutation and 2 acquired additional mutations, whereas 3 of 110 WT1-wild patients acquired novel mutations. In conclusion, WT1 mutations are correlated with poor prognosis in AML patients. The mutation status may be changed in some patients during AML progression.

Arsenic inhibition of telomerase transcription leads to genetic instability

Arsenic is effective in the treatment of acute promyelocytic leukemia. Paradoxically, it is also carcinogenic. In the process of elucidating a mechanism of arsenic resistance in a leukemia cell line, NB4, we discovered that arsenic exposure causes chromosomal abnormalities, with a preponderance of end-to-end fusions. These chromosomal end fusions suggested that telomerase activity may be inhibited by arsenic. We found that arsenic inhibits transcription of the hTERT gene, which encodes the reverse transcriptase subunit of human telomerase. This effect may in part be explained by decreased c-Myc and Sp1 transcription factor activities. Decreased telomerase activity leads to chromosomal end lesions, which promote either genomic instability and carcinogenesis or cancer cell death. These phenomena may explain the seemingly paradoxical carcinogenic and antitumor effects of arsenic.