No abstract available.
Aged ; Bone Marrow/pathology ; Genome, Human ; Humans ; Isochromosomes/*genetics ; Karyotyping ; Leukemia, Myeloid, Acute/complications/*diagnosis/genetics ; *Loss of Heterozygosity ; Male ; Oligonucleotide Array Sequence Analysis ; Thrombocytosis/*etiology

OBJECTIVETo assess the prevalence of several tyrosine kinases (TKs) gene mutations including c-Kit, FLT3 and JAK2 V617F in core binding factor related acute myeloid leukemia (CBF-AML), and analyze their impact on clinical characteristics and prognosis.

METHODSMutations of c-Kit, FLT3-ITD and FLT3-TKD were detected by genomic DNA PCR and sequencing, and JAK2 V617F mutation screening by allele-specific PCR in 58 newly diagnosed CBF-AML patients [28 AML with inv(16) and 30 with t(8;21)], and analyze the patients clinical characteristics and prognoses.

RESULTSc-Kit aberrations were detected in 32.8% cases, including 6 cases mutated in exon 8 (mutKIT8) and 13 mutated in exon 17 (mutKIT17). MutKIT8 was more prominent in inv(16) than in t(8;21) patients (21.4% vs 0, P = 0.009). Only 2 cases had FLT3-ITD and 7 (12.1%) FLT3-TKD mutations. The result of JAK2 V617F mutation screenings in these CBF-AML patients was negative. The frequency of receptor tyrosine kinases(RTK) mutations was 46.6% and only one case had two kinds of missense mutations (mutKIT8 & TKD(+)). Median age of onset was higher for mutKIT17 than for wide-type c-Kit (wtKIT) patients (55 vs 31, P = 0.003). c-Kit mutations were significantly associated with decreased overall survival (OS) and continuous complete remission (CCR) rates (P = 0.053, and 0.048 respectively), and so did more for exon17 mutated patients reduced (P = 0.005, and 0.013 respectively). FLT3-TKD mutation showed no effects on prognosis of CBF-AML patients.

CONCLUSIONSRTK mutations are common in patients with CBF-AML. c-Kit mutations frequently and JAK2V617F mutation rarely appear in CBF-AML. c-Kit mutations, especially mutKIT17 confers higher relapse risk and poorer prognosis.

Adolescent ; Adult ; Aged ; Core Binding Factors ; DNA Mutational Analysis ; Female ; Humans ; Janus Kinase 2 ; genetics ; Leukemia, Myeloid, Acute ; diagnosis ; etiology ; genetics ; Male ; Middle Aged ; Mutation ; Prognosis ; Protein-Tyrosine Kinases ; genetics ; Proto-Oncogene Proteins c-kit ; genetics ; Young Adult ; fms-Like Tyrosine Kinase 3 ; genetics

BACKGROUND: Therapy-related myeloid neoplasms (t-MN) occur as late complications of cytotoxic therapy. This study reviewed clinical and cytogenetic characteristics of patients with t-MN at a single institution in Korea. METHODS: The study subjects included 39 consecutive patients diagnosed with t-MN. Each subject's clinical history of previous diseases, treatments, and laboratory data was reviewed, including cytogenetics. The primary diagnosis was hematologic malignancy in 14 patients and solid tumor in 25 patients. RESULTS: Therapy-related acute myeloid leukemia (t-AML, 66.7%) was found to be more common than therapy-related myelodysplastic syndrome (t-MDS). Primary hematologic malignancies that were commonly implicated included mature B-cell neoplasm and acute leukemia. Breast cancer was the most common primary solid tumor. The mean time interval from cytotoxic therapy initiation to t-MN detection was 49 months. Chromosomal aberrations were observed in 35 patients, and loss of chromosome 5, 7, or both accounted for 41% of all cases. Balanced rearrangements occurred in 13 patients; these patients showed shorter latency intervals (mean, 38 months) than patients with loss of chromosome 5 or 7 (mean, 61 months). CONCLUSIONS: In this study, we determined the clinical and cytogenetic characteristics of Korean patients with t-MN. Although our results were generally consistent with those of previous reports, we found that t-MN resulting from de novo leukemia was common and that t-AML was more common than t-MDS at presentation. Multi-institutional studies involving a larger number of patients and additional parameters are required to investigate the epidemiology, genetic predisposition, and survival rate of t-MN in Korea.
Adolescent ; Adult ; Aged ; Antineoplastic Agents/*adverse effects/therapeutic use ; Asian Continental Ancestry Group ; Bone Marrow/pathology ; Breast Neoplasms/drug therapy/pathology/radiotherapy ; Child ; Child, Preschool ; Chromosome Aberrations ; Chromosomes, Human, Pair 5 ; Chromosomes, Human, Pair 7 ; Female ; Hematologic Neoplasms/drug therapy/pathology/radiotherapy ; Humans ; Karyotyping ; Leukemia, Myeloid, Acute/*diagnosis/etiology/genetics ; Male ; Middle Aged ; Myelodysplastic Syndromes/*diagnosis/etiology/genetics ; Neoplasms, Second Primary/*diagnosis/etiology/genetics ; Republic of Korea ; Young Adult