Influence of JAK2V617F allele burden on clinical phenotype of polycythemia vera patients: A study from India.

BACKGROUND: Elevated JAK2V617F allele burden is associated with enhanced expression of downstream target genes in Philadelphia negative chronic myeloproliferative neoplasms (CMPNs) which include PV, ET & PMF. Previous studies have shown the impact of JAK2V617F allele burden on clinical phenotype of CMPNs. However, there is no data from India regarding the association between JAK2V617F allele burden and clinical phenotype in PV. AIMS/SETTINGS AND DESIGN: We aimed to investigate the effect of allele burden on clinical phenotype in 90 JAK2V617F positive PV patients and to see its influence on disease related complications. MATERIAL AND METHODS: Allele burden of 90 JAK2V617F positive PV patients was quantified by Real-time polymerase chain reaction (RQ-PCR). RESULTS: 74/90 (82.22%) were males and 16/90 (17.78%) were females (median 45 years, range 35-78). Patients with age >50 years had significantly higher JAK2V617F allele burden (median 40.15%, range 0.49-91.62 %) than patients with ≤ 50 years age (median 48.59 %, range 0.56-86.74 %; P < 0.032). Patients with splenomegaly had significantly higher JAK2V617F allele burden (mean 50.24%, range 6.91-84.17%) than patients without splenomegaly (mean 33.82 %, range 0.49-71.83 %; P < 0.017). Patients with higher allele burden (median 57.20, range 43.4-72.03%) had significantly raised thrombotic events than the patients with lower allele burden (median 37.38, range 0.49-84.17%; P < 0.043). 49/90 (54%) were homozygous and 41/90 (46%) were heterozygous. CONCLUSIONS: Higher JAK2V617F allele burden showed association with increased age, splenomegaly and thrombotic events. Thus, it may be considered for prognostication and setting up the treatment protocol in PV patients.

Distribution of common BCR-ABL fusion transcripts and their impact on treatment response in Imatinib treated CML patients: A study from India.

BACKGROUND: Philadelphia chromosome (Ph): Hallmark of CML is caused by reciprocal translocation between chromosomes 9 and 22 resulting in BCR-ABL fusion protein. Most commonly associated breakpoint with CML is M-bcr in exon 13 or exon 14, producing splice variant b2a2 or b3a2 respectively. The distribution of these transcripts and their influence on clinico-hematological parameters is variable. Impact of the fusion transcripts on treatment outcome in Imatinib treated CML patients is still a matter of debate. AIMS/SETTINGS AND DESIGN: We conducted this study on 400 CML-CP patients to look for the distribution of fusion transcripts i.e. b3a2 and b2a2, their clinico-hematological profile and impact on treatment response in patients treated with Imatinib. MATERIAL AND METHODS: CML-CP was diagnosed by reverse transcriptase PCR (RT-PCR) for the BCR-ABL fusion transcript. Real-time quantitative PCR (RQ-PCR) was performed on peripheral blood every 3-6 monthly to look for treatment response. RESULTS: The overall frequency of b3a2 transcript was observed in 288 (72%) followed by b2a2 in 104 (26%) and hybrid fusion transcript (b3a2 + b2a2) was seen in 8 (2%) cases. MMR was attained in 198/288 (68.7%) patients with b3a2 transcript and 90/288 (31.3%) patients failed to achieve MMR after 12 months of Imatinib therapy. Among the patients with b2a2 transcript, 44/104 (42.3%) patients achieved MMR and 60/104 (57.7%) patients failed to achieve MMR after 12 months of Imatinib therapy. CONCLUSIONS: In conclusion, the frequency of b3a2 transcript was more as compared to b2a2 transcript. MMR was significantly higher in patients with b3a2 transcript as compared to patients with b2a2.

Comparative analysis of the Sokal, Euro and European Treatment and Outcome Study score in prognostication of Indian chronic myeloid leukemia-chronic phase patients on imatinib.

INTRODUCTION: The ultimate goal for CML management is risk stratification of the patients to design the appropriate treatment approach. The Sokal, Euro and EUTOS risk scores were established to prognosticate the patients on therapy. AIM: To perform a comparative assessment of the Sokal, Euro and EUTOS prognostic score in Indian CML-CP patients on imatinib. METHODS: This is a retrospective study performed in 260 Ph+ CML-CP patients who were administered oral imatinib (400 mg/day). RESULTS: 166/260 were males and 94/260 were females (M: F::1.6:1) with median age 35 years (range 20-70). 92 (35.38%), 125 (48.07%) and 43 (16.5%) patients were divided into low, intermediate and high risk Sokal score respectively. 102 (39.23%), 106 (40.76%) and 52 (20%) patients were discriminated into low, intermediate and high risk Euro score respectively. 210 (80.7%) and 50 (19.2%) patients were divided into low and high risk EUTOS score. Cumulative incidence of MMR for low, intermediate and high-risk Sokal score was 87%, 76% and 84% respectively (P = 0.016). Incidence of MMR in low, intermediate and high-risk Euro score was 93%, 85% and 68% respectively (P = 0.001). Incidence of MMR was 80 % and 81% for low and high risk EUTOS score (P = 0.764). Both EFS and OS are significantly correlated with Sokal score (P = 0.004, P = 0.007) and Euro score (P = 0.009, P = 0.001) but not with EUTOS score (P = 0.581, P = 0.927). CONCLUSION: The present study highlights the significant prognostic role of Sokal and Euro score in predicting the treatment outcome of the CML- CP patients on imatinib.

Association of JAK2V617F mutation with thrombosis in Indian patients with Philadelphia negative chronic myeloproliferative neoplasms.

BACKGROUND: : It is still a matter of debate regarding the association of JAK2V617F mutation with thrombosis in BCR-ABL negative CMPN patients. The role of JAK2V617F mutation in increasing the thrombotic risk in CMPNs is yet unequivocal. AIMS: : To clarify the contribution of JAK2V617F mutation in thrombosis in CMPN patients. SETTINGS AND DESIGN: This retrospective study was done to evaluate role of JAK2V617F mutation in thrombosis in CMPNs. MATERIALS AND METHODS: 65 CMPN patients (PV, ET and PMF) were analyzed for JAK2V617F mutation using ARMS-PCR and detailed history of thrombosis was recorded in these patients. STATISTICAL ANALYSIS: P values were 2 tailed, and statistical significance was set at P < 0.05. RESULTS: : 46/65 were males and 19/65 were females [M: F: 2.4:1] with median age 46 years [range, 14-80 years]. Patients had median Hb 15.6 g/dl [range, 5.1-20.3], median TLC 10.7 × 109/l [range 2.4-216] and platelet count 360 × 109/l [range, 20-1859]. 32 were JAK2V617F positive and 33 were negative for this mutation. On comparing the prevalence of thrombosis in JAK2V617F positive patients with JAK2V617F negative patients, we observed that 20/32 (62.5%) JAK2V617F positive patients had thrombosis as compared to 16/33 (48%) in JAK2V617F negative patients (P = 0.04). We observed significant association of JAK2V617F mutation with thrombosis, however no association of this mutation with thrombosis was observed among the JAK2V617F negative patients. CONCLUSION: Our study suggests that JAK2V617F mutation may increase the risk of thrombosis in CMPNs. This finding could lead to risk stratification, setting up the treatment strategy in CMPNs.

Reversal of Glanzmann thrombasthenia platelet phenotype after imatinib treatment in a pediatric chronic myeloid leukemia patient.

Chronic Myelogenous Leukemia (CML) is a myeloproliferative neoplasm characterized by proliferation of Philadelphia positive clonal pluripotent hematopoietic cells. Bleeding is a rare presentation of CML that can occur due to platelet dysfunction. Both pre-treatment and post-treatment platelet function abnormalities in CML have been described in the literature. We describe a rare case of childhood CML who presented with mucocutateous bleeding manifestations. On laboratory workup, a Glanzmann Thrombasthenia (GT) like platelet phenotype was demonstrated along with confirmation of diagnosis of CML in chronic phase. The acquired nature of platelet function defect was confirmed by demonstrating recovery of platelet antigens glycoprotein IIb/IIIa after achieving complete hematological response with Imatinib. Due to presenting complaint of bleeding diathesis and absence of hepatosplenomegaly, the case was undiagnosed for CML until the patient reported to us. Careful evaluation of complete blood counts, peripheral blood picture and detailed laboratory workup was the window to proper diagnosis and treatment in this case.

NPM1 and FLT3 mutations in acute myeloid leukemia with normal karyotype: Indian perspective.

BACKGROUND: FLT3-ITD and NPM1 mutations are considered to be the major determinants of the patient response to therapy and outcome. The primary aim of this study was to establish the correlation between these molecular mutations and the clinico-hematologic parameters as well as the prognostic outcome of the Indian acute myeloid leukemia (AML) patients. MATERIALS AND METHODS: This prospective study involved newly diagnosed nonpromyelocytic AML patients who had undergone complete diagnostic workup, including immunophenotyping, conventional cytogenetics and molecular analysis for NPM1 and FLT3-ITD mutation by reverse transcriptase polymerase chain reaction at presentation. RESULTS: Overall, the prevalence of NPM1 and FLT3-ITD mutations was found to be 14.4% and 10.8%, respectively. Among patients with normal karyotype, leukocytosis was significantly associated with NPM1+ group than the NPM1- group (P = 0.0019) and more severe degree of anemia was observed in the FLT3-ITD+ patients than the other groups (P = 0.025). No significant correlation was found in terms of age at presentation (P = 0.56), sex ratio (P = 0.467), median platelet count (P = 0.27), and blast percentage between NPM1+ and FLT3-ITD+ groups. Complete remission (CR) rates were better in the NPM1+/FLT3-ITD- group than the other three groups. Unlike most other studies, improved CR rates as well as disease-free survival were observed in the NPM-/FLT3-ITD- group than the FLT3-ITD+ groups although not reaching statistically significant levels. CONCLUSION: Some differences in the clinical behavior of the Indian AML patients in comparison to that of the West in the presence of NPM1 and FLT3-ITD suggests that comprehensive studies are required to confirm the definitive role of these mutations among AML patients, especially with normal karyotype.

Does Indian Myelodysplastic Syndrome Have a Biology Different from That in the West ?

abstract.

Correlation of JAK2V617F mutational status in primary myelofibrosis with clinico-hematologic characteristics and international prognostic scoring system scoring: a single center experience.

INTRODUCTION: Somatic mutation in the exon 14 of Janus Kinase 2 gene is an established diagnostic marker in bcr-abl negative myeloproliferative neoplasms, especially primary idiopathic myelofibrosis (PIMF). AIM: Our primary aim was to find out the correlation between the JAK2V617F mutational status and the clinico-hematologic characteristics, as well as the international prognostic scoring system (IPSS) scoring of patients with PIMF. MATERIALS AND METHODS: Clinical and hematologic features were reviewed for 68 patients with primary idiopathic myelofibrosis (PIMF). JAK2V617F mutation status was analyzed by amplification refractory mutation screening-polymerase chain reaction. The patients were further stratified into low, intermediate-1, intermediate-2 and high-risk groups on the basis of IPSS scoring. RESULTS: The JAK2V617F mutation was detected in 58.8% patients. Univariate analysis of variables at presentation identified that JAK2V617F negative patients were significantly associated with more severe anemia (P = 0.045), younger age (P = 0.008), higher transfusion requirement (P = 0.017), and thrombocytopenia (P = 0.015). Patients who were homozygous for JAK2V617F mutation were associated with thrombocytosis (P = 0.014) and also had higher median total leucocyte count (P = 0.20) than the other groups. No significant correlation was detected between JAK2V617F mutational status and the presence of constitutional symptoms, spleen size, grade of bone marrow fibrosis or prognostic risk stratification of the PIMF patients. CONCLUSION: The variations in the prognostic implication of PIMF patients with mutation status as stated by various publications worldwide, reinstates the need for larger prospective studies using standardized JAK2V617F quantification methods as well as estimation of other newer molecular markers to develop deeper insight into various molecular alterations involving PIMF patients in India as well as worldwide.

C1236T polymorphism in MDR1 gene correlates with therapeutic response to imatinib mesylate in Indian patients with chronic myeloid leukaemia.

Patients with chronic myeloid leukaemia show an excellent response to treatment with imatinib. However, in some patients, the disease is resistant to imatinib. This resistance may be related to the presence of genetic variations on the drug's pharmacokinetics and metabolism. We therefore studied three polymorphisms (C1236T, G2677T and C3435T) in the human multidrug-resistance gene (MDR1) in 86 patients with chronic myeloid leukaemia treated with imatinib. Imatinib resistance was more frequent in patients with TT genotype at locus 1236 than in those with CT/CC genotypes (p=0.003). For the other two loci (G2677T and C3435T), resistance was seen to be higher for TT genotype when compared to GG/GT and CT/CC but it was not statistically significant (p=0.13 and p=0.099). In conclusion, determination of C1236T MDR1 genotype may help to predict response to imatinib therapy in patients with chronic myeloid leukaemia.