Incidence and clinical significance of FLT3 and nucleophosmin mutation in childhood acute myeloid leukemia in Chile

Abstract Introduction Acute myeloid leukemia (AML) is a heterogeneous disease and approximately one-third of its carriers do not have evident genetic abnormalities. The mutation of specific molecular markers, such as fms-like tyrosine kinase 3 (FTL3) internal tandem duplication (ITD), FLT3 tyrosine kinase domain (TKD) and nucleophosmin (NPM1), are associated with an adverse and favorable prognosis, respectively. Objective The objective was to determine the prevalence of FLT3/ITD and NPM1 in Chilean patients and their association with clinical data and prognosis. Method and Results Two hundred and thirty-two children were studied between 2011 and 2017, the median being 8.6 years (ranging from 1 to 18 months). Acute promyelocytic leukemia (APL) was diagnosed in 29%. The FLT3/ITD-mutated in non-promyelocytic AML was at 10% (14/133) and the FLT3/TKD, at 3.7% (2/54). In APL, it was at 25.4% (16/63). In non-promyelocytic AML, the FLT3/ITD-mutated was associated with a high leucocyte count, the median being 28.5 x mm3 (n= 14) versus 19.4 x mm3 (n= 119), (p= 0.25), in non-mutated cases. In APL, the median was 33.6 x mm3 (n= 15) versus 2.8 x mm3 (n= 47), (p < 0.001). The five-year overall survival (OS) in non-promyelocytic AML with non-mutated and mutated FLT3/ITD were 62.7% and 21.4%, respectively, (p < 0.001); the 5-year event-free survival (EFS) were 79.5% and 50%, respectively, (p < 0.01). The five-year OS in APL with non-mutated and mutated FLT3/ITD was 84.7% and 62.5%, respectively, (p= 0.05); the 5-year EFS was 84.7% and 68.8%, respectively, (p= 0.122). The NPM1 mutation was observed in 3.2% (5/155), all non-promyelocytic AML with the normal karyotype. Conclusion The FLT3/ITD mutation was observed more frequently in APL and associated with a higher white cell count at diagnosis. However, the most important finding was that the FLT3/ITD mutation was associated with a shorter survival in non-promyelocytic AML.

The clinical observation of relapsed or refractory acute myeloid leukemia in patients with high CD117 expression but no FLT3-ITD mutation treated with sorafenib alone / 天津医药

@#Objective To make a primary investigation of outcomes in relapsed or refractory (R/R) acute myeloid leukemia (AML) patients who were FLT3-ITD mutation negative and treated with sorafinib alone. Methods The clinical responses and survival of R/R AML patients who underwent sorafenib treatment only were retrospectively analyzed. The side effects and response results were assessed according to common terminology criteria for adverse events (CTCAE) v 4.0 from US National Institutes of Health and NCCN guideline. Results Four out of seven patients achieved complete remission by sorafenib treatment alone. The median time required for remission was 36 days in the four patients. Among them, only 1 patient stopped the maintenance treatment because of side effect of serious skin lesion. Three patients showed no response to sorafenib, including 2 accepted stem cell transplantation and 1 retrieved to salvage chemotherapy. All of them achieved complete remission later. One patient developed grade 1 adverse event of liver. Another one developed grade 3 skin lesion. All patients experienced neutropenia of more than 7 days without unendurable infections and early deaths. The median follow-up time for the whole cohort was more than 22 months. Three patients passed away for relapse of AML and their disease-free survival time with sorafenib ranged from 2 to 20 months. All four patients accepted stem cell transplantation were still surviving no matter whether or not they were responsive to sorafinib before. The median survival time for these seven patients was 650 days. Conclusion The R/R AML patients with negative FLT3-ITD mutation and high expression of CD117 treated with sorafenib alone have good remission and long term survival.

Effect of FLT3-ITD with DNMT3A R882 double-mutation on the prognosis of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation / 中华血液学杂志

Objective@#To investigate the impact of FLT3-ITD and DNMT3A R882 double mutations to the prognosis of acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT).@*Methods@#FLT3-ITD, DNMT3A, C-kit, CEBPA, FLT3-TKD and NPM1 mutations were detected in 206 newly diagnosed AML patients by Sanger sequencing (M3 and those received FLT3 inhibitor were excluded). Clinical data of AML patients were retrospectively analyzed to compare the prognosis of each gene mutation group.@*Results@#①Of 206 patients, 104 were male and 102 female with a median age of 38 (3-63) years, including 6 cases of M0, 24 cases of M1, 56 cases of M2, 39 cases of M4, 63 cases of M5, 6 cases of M6 and 12 unclassified cases. ②All 206 patients were divided into four groups according to the mutation gene at the time of diagnosis: FLT3-ITD+ DNMT3A R882+ group (group A), FLT3-ITD+ DNMT3A R882- group (group B), FLT3-ITD- DNMT3A R882+ group (group C) and FLT3-ITD- DNMT3A R882- groups (group D). Gender, leukocyte count at diagnosis, chromosome karyotype, the median age, FAB classification, disease status prior to transplantation, type of donor, conditioning regimen and GVHD were not significantly different between four groups (P>0.05). ③The 2-year cumulative recurrence rate (CIR) of group A was significantly higher than that of other groups [group A (72.2±2.6)%, group B (38.6±0.6)%, group C (36.8±1.6)%, group D (27.8±0.1)%, respectively, P<0.05], while the 2-year overall survival (OS) rate and 2-year leukocyte-free survival (LFS) rate were lower than those of other groups [group A (30.9±13.3)%, (11.3±10.2)%; group B (67.5±7.8)%, (47.9±8.4)%; group C (61.4±12.4)%, (56.8±12.5)%; group D (80.1±3.7)%, (79.7±3.6)%, respectively, P<0.05].@*Conclusion@#AML patients with FLT3-ITD and DNMT3A R882 double mutations had a very high CIR and low OS, LFS after transplantation.

The analysis of prognosis-associated factors in adults with acute promyelocytic leukemia / 中华血液学杂志

Objective@#To explore the prognostic value of CD34, CD2, CD56 expressions and FLT3-ITD mutation in adults with acute promyelocytic leukemia (APL) .@*Methods@#The immuno-phenotypic and molecular characteristics of 137 adult patients with APL (from January 2010 to March 2016, in Henan Provincial People’s Hospital) were investigated. And the relationships between CD34, CD2, CD56 expressions, FLT3-ITD mutation and the outcomes of high WBC counts at onset, complete remission (CR) rate, early mortality, relapse rate (RR) , overall survival (OS) , disease free survival (DFS) were explored.@*Results@#①Among the 137 patients, the positive ratios of CD34, CD2, CD56 expressions and mutation rate of FLT3-ITD were 26.3%, 25.5%, 10.2% and 17.5%, respectively. The morbidities of positive CD34, CD2, CD56 expressions and FLT3-ITD mutation in the high-risk group were 43.2%, 47.7%, 18.2% and 27.3% respectively, while those in the low-/intermediate-risk groups were 18.3%, 15.1%, 6.5% and 12.9%, respectively (P<0.05) . ②At a median follow-up of 41 months, the total CR rate of the 137 adults APL patients was 96.9%, early mortality 6.6% and relapse rate 7.3% respectively. And RR of positive CD34 or CD2 expression patients was higher than negative CD34/CD2 expression ones (18.8% vs 3.3%, χ2=8.462, P=0.004; 16.1% vs 4.3%, χ2=4.382, P=0.028, respectively) . In addition, the early mortality of patients with positive CD56 expression or FLT3-ITD mutation was extremely higher than in negative ones (21.4% vs 4.9%, χ2=5.610, P=0.018; 16.7% vs 4.4%, χ2=4.833, P=0.028, respectively) . ③The whole OS and DFS were 88.3% and 84.7%, respectively. Wherein, OS and DFS in patients with CD34+, CD56+ or FLT3-ITD mutation were worse (P<0.05) .@*Conclusions@#Positive CD34, CD2, CD56 expression and FLT3-ITD mutation were latent poor prognostic factors in adults with APL.

Sorafenib in combination with chemotherapy as first-line therapy for FLT3-ITD positive acute myeloid leukemia / 中华血液学杂志

Objective@#To analyze the clinical features of acute myeloid leukemia patients with Fms-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) mutation and the therapeutic effect of sorafenib in combination with chemotherapy as first-line therapy for these patients.@*Methods@#Clinical features and therapeutic effect were retrospectively analyzed in 53 AML patients with FLT3-ITD mutation diagnosed in Henan Cancer Hospital from January 2013 to August 2016. The biological characteristics and clinical efficacy of chemotherapy in combination with or without Sorafeinb were analyzed.@*Results@#FLT3-ITD mutation was identified in 53 AML patients, 22 cases (41.5%) were M5 subtype. The median of the peripheral WBC was 61.00 (0.98-920.00) ×109/L, and there were 50 (94.3%) patients with WBC>10×109/L. The median of blast cell in bone marrow was 0.730 (0.234-0.966) . The total remission rate of all these 53 patients was 56.6% (30/53) . The complete remission (CR) rates in patients treated with chemotherapy in combination with sorafenib and patients with chemotherapy alone were 86.4% (19/22) and 35.5% (11/31) , respectively. The 1-year overall survival rates of the two groups were 78.3%% and 50.0% (P=0.041) , and 1-year progression free survival rates were 75.9% and 42.4% (P=0.044) , respectively.@*Conclusion@#AML patients with FLT3-ITD mutation have the characteristics of high peripheral WBC, high blast cells in bone marrow and accompanying with M5 subtype. Sorafeinb combined with chemotherapy can significantly improve CR rate and short term survival.

Analysis of the presence of FLT3 gene mutation and association with prognostic factors in adult and pediatric acute leukemia patients

ABSTRACT When the FLT3 gene is mutated, it originates a modified receptor with structural changes, which give survival advantage and malignant hematopoietic cell proliferation. Thus, the presence of mutations in this gene is considered an unfavorable prognostic factor. A total of 85 consecutive samples of newly diagnosed untreated patients with AL were included in the study after they provided their informed consent. FLT3 gene mutations were detected by PCR. For the pediatric group, a positive correlation was observed between WBC count and the presence of FLT3-ITD in patients with AML and ALL. Furthermore, children with AML who had the FLT3-ITD mutation showed a tendency to express CD34 in blast cells. In the adult group, the AML patients with FLT3-ITD who expressed CD34 in blast cells had a tendency to worse progression. The present data indicate no association between the prognostic factors evaluated and FLT3 gene mutations in adult with AL. Yet, the presence of FLT3-ITD mutation was significantly related with WBC count in the pediatric group. These findings demonstrate that FLT3 gene mutations can be considered as independent poor prognostic factors.

Clinical outcome of FLT3-ITD (+) acute myeloid leukemia patients treated with allogeneic hematopoietic stem cell transplantation / 中华内科杂志

Objective To study the clinical outcome of patients with fns-like tyrosine kinase-3internal tandem duplication (FLT3-ITD) positive acute myeloid leukemia (AML) treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT) and to explore the potential prognostic factors to patients' survival including transplant types or disease status.Methods A total of 314 AML patients in our center from October 2006 to October 2012 were retrospectively analyzed,among whom,54 patients were defined with FLT3-ITD positive.Survival rates and treatment-related mortality were further analyzed.Results For all 54 FLT3-ITD positive patients,the 3-year overall survival (3-OS) rate was 56％ and 3-year leukemia-free survival (3-LFS) rate was 47％.The outcome of haplo-identical HSCT was similar as that of sibling donors(3-OS rate:60％ vs 54％ ; 3-LFS rate:54％ vs 45％,respectively).There were 47 patients who received transplantation in first complete remission(CR1).The other 7 patients were of disease relapse or in CR2 before transplantation.Not surprisingly,patients in CR1 had better prognosis than those in nonCR1.Conclusions Allo-HSCT is an effective treatment for AML patients with FLT3-ITD positive mutation.The survival outcome of haplo-identical HSCT was comparable with that of sibling donors.Relapse of AML was the dominant factor related to the mortality of FLT3-ITD positive AML patients after allo-HSCT.

Meta analysis on the relationship between cuplike nuclei morphology and FLT3-ITD mutation in acute myeloid leukemia / 白血病·淋巴瘤

ObjectiveTo investigate the association between cuplike nuclei morphology and FLT3-ITD mutation, so as to provide evidence for the minor classification of AML. MethodsThe articles on the association of cuplike nuclei morphology and FLT3-ITD mutation were retrieved by searching international and national databases from 1999 to 2011. The relationship was assessed by meta analysis with Statal 1 software.The OR value and confidence interval(CI)were calculated, and the publication bias was assessed by Begg test and Egger test.ResultsThere was significant difference between cuplike nuclei morphology appearance and FLT3-ITD mutation (OR =2.59,95 ％ CI 1.55-4.33,P =0.00).Results from both Begg' s test and Egger’ s test did not show significant difference indicating that there was no publication bias existed.ConclusionThe uncommon morphologic variant of AML with cuplike nuclei is highly associated with FLT3-ITD mutation, and the presence of cuplike nuclei in AML represents a distinctive morphologic finding that can be used to prioritize the molecular workup of patients with AML.

The expression and clinical significance of FLT3/ITD gene mutation in hematologic malignancies / 中国实用内科杂志

Objective To explore Fms-like tyrosine kinase 3(FLT3)gene internal-tandem duplications(ITD)mutation in hematologic malignancy.Methods FLT3/ITD gene mutation was analyzed by polymerase chain reaction(PCR)amplification on the DNA samples from 332 patients with hematologic malignancies at the Nanfang Hospital from 2001 to 2005.Results The mutation of FLT3/ITD gene was detected in 22.3% acute myeloid leukemia(AML)cases,in 6.5% chronic myeloid leukemia(CML)-blast crisis(BC)cases,in 5.6% myelodysplastic syndromes(MDS)cases and in 2.6% acute lymphoblastic leukemia(ALL)cases;FLT3/ITD gene mutation was not detected in CML-chronic phase(CP),multiple myeloma(MM),non-Hodgkin lymphoma(NHL)and chronic lymphocytic leukemia(CLL)cases.FLT3/ITD+ AML indicate high white blood cell count and high percentage of bone marrow blast cells and had a unfavourable cumulative relapse rates.Conclusion AML patients with FLT3/ITD have a poor prognosis.Detection of FLT3/ITD gene mutation may be valuable in hematologic malignancy.