Mayur Parihar

Metabolic reprogramming of bone marrow stromal cells by leukemic extracellular vesicles in acute lymphoblastic leukemia

To the editor: Cancer cells produce unique heterogeneous vesicles[1][1] capable of transferring oncogenic material[2][2],[3][3] to other cells,[4][4],[5][5] with the potential of modulating a tumor-supportive environment.[6][6][⇓][7]-[8][8] We have previously reported the presence of lipid-

Cytogenetic analysis of acute myeloid leukemia with t(8;21) from a tertiary care center in India with correlation between clinicopathologic characteristics and molecular analysis

Abstract The t(8;21)(q22;q22) is the most common translocation in acute myeloid leukemia (AML). We describe the clinicopathologic and cytogenetic profile of 117 patients with t(8;21) AML. There were 76 males and 88 adults. The median age was 26 years. Most patients (80%) had AML M2. Dysplasia was present in 68% of patients and eosinophilia in 18%. Eight patients had fewer than 20% blasts. Additional chromosomal aberrations were seen in 103 patients (88%) with loss of a sex chromosome (LSC) in 78 patients (66%) and deletion 9q in 21 (18%). The other recurrent abnormalities were trisomies 4, 8 and 15, monosomy 17 and deletion 7q (less than 5% each). Three- or four-way variant t(8;21) were seen in 6% of patients and 3% had tetraploidy. Aberrant expression of CD19 was seen in 54% of patients. FLT3 mutations were seen in 7.5% of patients (3/40) and c-KIT mutations in 6.6% (2/30). None had NPM1 or JAK2 V617F mutations. One patient had a granulocytic sarcoma. Complete remission was achieved in 96% of the 26 newly diagnosed patients after first induction. The median follow-up was 25 months (range 4–68). The overall survival was 69% at 31 months.

Mosaic double aneuploidy: Down syndrome and XYY.

Chromosomal abnormalities are seen in nearly 1% of live born infants. We report a 5-year-old boy with the clinical features of Down syndrome, which is the most common human aneuploidy. Cytogenetic analysis showed a mosaicism for a double aneuploidy, Down syndrome and XYY. The karyotype was 47, XY,+21[19]/48, XYY,+21[6]. ish XYY (DXZ1 × 1, DYZ1 × 2). Mosaic double aneuploidies are very rare and features of only one of the aneuploidies may predominate in childhood. Cytogenetic analysis is recommended even if the typical features of a recognized aneuploidy are present so that any associated abnormality may be detected. This will enable early intervention to provide the adequate supportive care and management.

Clinicopathological features of hepatosplenic T cell lymphoma: a single centre experience from India

Abstract In a first series from India, we report 9 cases of hepatosplenic T cell lymphoma (HSTCL) seen in 23 months accounting for 4.2% of all mature T-non-Hodgkin lymphomas (NHLs) in our institution. All patients presented with organomegaly, cytopenias and had evidence of bone marrow involvement. The tumor cells had a blastic (55%) morphology with predominantly intrasinusoidal (33.3%) or intrasinusoidal with an additional interstitial component (33.3%). On flow cytometry, the classical phenotype (CD3+, CD7+, CD4−, CD8−, CD5−, CD56+/−) was seen only in 4 patients. Unusual variations included CD45 (overexpression), CD7 (dim expression), CD3 (overexpression, heterogeneous and dim), CD2 (overexpression), CD5 (heterogeneous), CD8 (heterogeneous or dim or overexpression) and aberrant expression of CD19. Fluoresvent in situ hybridisation (FISH) and karyotyping was abnormal in 5 out of 7 patients evaluated. All of the 5 cases showed abnormalities in chromosome 7 (ring chromosome or isochromosome 7q). Five patients died of disease and related complications in a span of 1–3 months after diagnosis whereas 4 were alive at their last follow up out of which 2 had documented a relapse. In our series, HSTCL was characterized by typical clinical and variable immunophenotypic features and a dismal clinical outcome.

Mixed-phenotypic acute leukemia series from tertiary care center

Introduction: Mixed-phenotype acute leukemias (MPALs) are a heterogeneous group of rare leukemias constituting approximately 2%–5% of all leukemias, in which assigning a single lineage of origin is not possible. They are diagnosed by either the presence of antigens of more than one lineage or by the presence of dual population of blasts belonging to two or more lineages. We highlight the clinicopathological, immunophenotype, and genetic data of a cohort (n = 14) of patients diagnosed and treated at our center. Materials and Methods: We retrospectively analyzed consecutive cases of MPAL diagnosed in our flow cytometry laboratory from May 2012 to August 2015. These cases were diagnosed based on immunophenotyping of peripheral blood/bone marrow aspirates and morphology/genetics wherever available as per the World Health Organization (WHO) 2008 guideline. Results: Among 628 consecutive acute leukemia (AL) cases diagnosed and evaluated during this period, we identified 14 (2.2%) patients with MPAL fulfilling WHO 2008/EGIL criteria for immunological characterizing of AL criteria. Majority of these were males (n = 8, male:female ratio 1.3:1) and adults (n = 11, 78.5%). The median age of this cohort was 41 years (range 2–80). These cases were further classified as: B/myeloid (n = 9), T/myeloid (n = 4), and B/T MPAL (n = 1). Cytogenetics was available in 12 out of 14 cases, out of which, three cases had normal karyotype, three with t(9;22)(q34;q11), and two cases with complex karyotype. We also came across a rare case of B + T lymphoid MPAL who had mixed-lineage leukemia gene t(v; 11q23) rearrangement. Conclusion: MPAL is a complex entity with heterogeneous clinical, immunophenotypic, cytogenetic, and molecular features. Multiparametric flowcytometry by using comprehensive antibody panels is a valuable tool for diagnosis. Subsequent cytogenetic and molecular analysis for further prognostic stratification and treatment modalities are important.

Jumping translocation in a case of de novo infant acute myeloid leukemia.

An infant presented with fever and purulent discharge from the left ear, proptosis of the right eye, and hepatosplenomegaly. She was diagnosed with acute monoblastic leukemia on morphological and flowcytometric analysis of the bone marrow. Karyotyping showed a jumping translocation (JT) involving the long arm of chromosome 1 as the sole cytogenetic abnormality in 29 metaphases. The patient died within 2 months of diagnosis. The presence of JT in a de novo infant AML as a sole cytogenetic abnormality indicates its possible role in leukemogenesis unlike previous reports that have implicated its role in tumor progression only. Pediatr Blood Cancer 2014;61:387–389.

Novel t(2;12)(q31;p13) in a case of pediatric T-cell acute lymphoblastic leukemia.

Background: The role of ETV6 in B-cell acute lymphoblastic leukemia (ALL) has been extensively studied, whereas only rare cases of ETV6 involvement in pediatric T-cell ALL have been described. Observation: We report a case of T-cell ALL in a 13-year-old boy with t(2;12)(q31;p13) involving ETV6, resulting in the relocation of the ETV6 from 12p13 to 2q31 locus that harbors the class 1 homeobox gene (HOX) cluster D, which is expressed during the early stages of T-cell development. Conclusions: We report a novel translocation in T-cell ALL highlighting the involvement of ETV6 and potentially the HOXD gene cluster in a case of T-cell ALL.

Loss of chromosome Y in acute lymphoblastic leukemia: Age related or neoplastic phenomenon?

Loss of chromosome Y (LOY) in the bone marrow has long been considered as an age-related phenomenon with an incidence of more than 25% in males beyond the age of 80 years. Though reported as an acquired abnormality in myeloid neoplasms, it has rarely been described in B-lymphoblastic leukemia which primarily is a disease of the young. We describe here in three cases of pediatric B-lymphoblastic leukemia with LOY. Conventional cytogenetic studies and fluorescence in situ hybridization studies using centromeric probes for chromosome X and Y on peripheral blood samples ruled out constitutional LOY in all the three cases favoring it to be a neoplastic phenomenon.

TP53 Mutation, MYCN Amplification, and Large Cell/Anaplastic Histology in Medulloblastoma

To the Editor: A 2.5-y-old girl had headache and vomiting for one month. She was referred following subtotal excision of a posterior fossa mass, with postoperative mutism, hypotonia and hemiparesis. MRI brain demonstrated residual disease (Fig. 1a). Spine showed meningeal enhancement. Cerebrospinal fluid (CSF) demonstrated malignant cells. Histopathology suggested medulloblastoma, large cell/anaplastic (LCA) variant (Fig. 1c). Age < 3 y, residual tumor >1.5cm and M1 stage classified her as ‘high risk.’ She was started on chemotherapy (vincristine, cisplatin, cyclophosphamide) with plan for radiotherapy once she would complete 3 y of age. Initial clinical improvement was noted in weakness and verbal output. TP53 mutation was detected on Sanger sequencing (Fig. 1f). Insitu hybridization demonstrated cells with deletion of TP53 gene and amplification of MYCN (Fig. 1d, e). After cycle-2 of chemotherapy she had recurrence of headache, irritability and vomiting. MRI was suggestive of progressive disease (Fig. 1b). The family opted for palliative care. The child died a month later. Developing countries lack access to molecular subgrouping of medulloblastoma [1] . Immunohistochemical correlates have limitations [2]. We used in-situ hybridization and Sanger sequencing to diagnose MYCN amplification and TP53 mutation respectively. TP53 mutations do not alter prognosis in the WNT-subtype, but are associated with dismal prognosis in the SHH-subgroup. Loss of chromosome 17p is observed in the latter and was present in our patient [3]. MYCN, when amplified and intrinsically deregulated, induces and maintains SHH-medulloblastoma progression [4]. LCA pathology (p = 0·00050), MYCN amplification (p < 0·0001), and TP53 mutations (p < 0·0001) are enriched in the recently reported ‘MBSHH-Child’ subgroup [1]. In presence of incomplete resection, this disease would classify as ‘very high risk’ [1]. These tumors are refractory to current treatment strategies. Chromothripsis results in radiation resistance and promotes radiation induced genomic instability. Though commoner in older children >3 y, our case demonstrates that a combination of age with other parameters, rather than an absolute cut-off , is important in riskstratification [5]. In conclusion, the triad of LCA morphology, TP53 mutation and MYCN amplification, with incomplete resection, correctly predicted medulloblastoma at high risk of treatment failure in this young child. While this information aided prognostication, novel strategies are plausibly needed for these patients, including limiting radiation, and using lithium for selective WNT * Anirban Das anirban.das13@gmail.com;

MYD88 and CXCR4 Mutation Profiling in Lymphoplasmacytic Lymphoma/Waldenstrom’s Macroglobulinaemia

Recurrent mutations affecting MYD88 and CXCR4 gene nowadays form the basis for the diagnosis, risk stratification and use of inhibitors targeting these signalling pathways in LPL/WM which are rare B cell neoplasms. MYD88 L265P mutation analysis was performed on 33 cases of LPL/WM by AS-PCR (positivity-84.8%, n = 28/33) and by Sanger sequencing (positivity-39.3%, n = 13/33). We had only two cases with CXCR4 non-sense (NS) mutation (p.S338*) using Sanger sequencing. MYD88 (L265P) mutation detection by AS-PCR can form reliable biomarker for the diagnosis of LPL/WM in molecular labs. Although the cohort is small, still the CXCR4 mutation frequency in our study is low as compared to the published literature.