Neeraj Arora

Gastrointestinal lymphomas: Pattern of distribution and histological subtypes: 10 years experience in a tertiary centre in South India

BACKGROUND AND AIM Gastrointestinal tract (GIT) is one of the major sites of extra-nodal lymphomas constituting 10-15% of all non-Hodgkins lymphoma cases and about 30-40% of extra-nodal lymphomas. Considerable variation exists in the literature with respect to incidence of the various histological subtypes and sites of involvement. This study was undertaken to ascertain the anatomic distribution, histological subtypes and sites of all GIT lymphomas presenting to a tertiary referral hospital in southern India. MATERIALS AND METHODS The histological material of 361 patients over a period of 10 years (2001-2010), with histopathological diagnosis of lymphoma involving the GIT (both primary and secondary), was analyzed retrospectively. All lymphomas were reclassified according to the World Health Organization 2008 classification. RESULTS These 361 cases include 336 primary and 25 cases of lymphomas, where the involvement was secondary. Primary lymphomas consisted of 267 males (79.64%) and 68 females (20.24%) with a male:female ratio of 3.93:1. The mean age was 45 years (range 3-88). Diffuse large B-cell lymphoma (DLBCL) was the commonest subtype (222 cases; 66.71%), followed by low-grade marginal zone lymphoma of the mucosa associated lymphoid tissue (MALT) type (34 cases; 10.12%) and Burkitts lymphoma (35 cases; 10.48%). The commonest site was stomach (180 cases; 53.57%), followed by small intestine (79 cases; 23.51%) and large intestine (68 cases; 20.23%), respectively. There were some uncommon types of GIT lymphomas documented during the study. CONCLUSION In this largest retrospective single centre study from India, we establish that the pattern of distribution of primary GIT lymphomas (PGLs) in India is similar to the western literature in that the stomach is the commonest site of PGL and DLBCL is the commonest histological subtype. Immunoproliferative small intestinal disease cases were seen in this study, which is uncommon in the west.

Frequency and distribution of lymphoma types in a tertiary care hospital in South India: analysis of 5115 cases using the World Health Organization 2008 classification and comparison with world literature

Abstract This study aimed to analyze the distribution of lymphoid neoplasms in a single tertiary care center in India using the World Health Organization (WHO) 2008 classification. Histological material of 5115 patients with histopathological diagnosis of lymphoma, diagnosed over a period of 10 years (2001–2010), was analyzed retrospectively. Hodgkin lymphoma (HL) constituted 21.3% (n = 1089) and non-Hodgkin lymphomas (NHLs) constituted 78.7% (n = 4026). Of these, B-cell neoplasms accounted for 78.6% (n = 3166) and T-cell/natural killer (NK)-cell neoplasms 20.2% (n = 815) of the NHLs. The commonest subtype of NHL was diffuse large B-cell lymphoma (n = 1886, 46.9%). The frequency of peripheral T-cell/NK-cell lymphomas in this study was higher than in the Western literature but less than the frequency documented in some Asian countries. Similar to the Western literature but in contrast to previous Indian studies, peripheral T-cell lymphoma, not otherwise specified (PTCL NOS) (n = 238) was the commonest histological subtype of T-cell/NK-cell NHL in this study and constituted 5.9% of the total NHLs. Mixed cellularity (MC-CHL) (n = 488, 45%) was the major subtype of HL. Primary extranodal lymphoma (ENL) accounted for 32.8% (n = 1321) of all NHLs and most frequently involved the gastrointestinal tract. This study also documents the frequency of many rare types of lymphoma in South India.

Next-generation sequencing unravels homozygous mutation in glucose-6-phosphate isomerase, GPIc.1040G > A (p.Arg347His) causing hemolysis in an Indian infant

INTRODUCTION Inherited anemias diagnostic workup requires a step-wise algorithm. Causal genes implicated in congenital hemolytic anemia are numerous, making a gene-by-gene approach by Sanger sequencing time consuming, expensive and labour intensive. Targeted resequencing can be of great use in explaining these cases. METHODOLOGY Six months female presented with neonatal jaundice and negative family history. Clinical and laboratory evidences were suggestive of hemolytic anemia. G6PD deficiency, thalassemias, hemoglobinopathies, autoimmune hemolytic anemia, hereditary spherocytosis and pyruvate kinase deficiency were excluded. Targeted resequencing on Illumina MiSeq using TruSight One sequencing panel was performed to identify the causative mutations. RESULTS 35-40% of RBCs were acanthocytes and echinocytes. A missense homozygous mutation was found inglucose-6-phosphate isomerase, GPI [c.1040G>A (p.Arg347His), rs137853583] which results in nonspherocytic hemolytic anemia. CONCLUSION This study describes GPI p.Arg347His mutation for the first time from India and is the first report of red cell GPI deficiency diagnosed using NGS-based resequencing and highlights the potential of this technique in clinical practice.

Molecular basis of quantitative fibrinogen disorders in 27 patients from India

Congenital fibrinogen deficiency is an extremely rare (1:1 000 000) hereditary bleeding disorder caused by defects in genes coding for fibrinogen Aα‐, Bβ‐ and γ‐chains, respectively. We report here the molecular basis of fibrinogen deficiency in a large series of patients from India. Twenty‐seven patients with clinical features suggestive of fibrinogen deficiency and with prolonged plasma clotting times and low fibrinogen levels were studied. Genomic DNA was screened for mutations in the fibrinogen alpha (FGA), beta (FGB), gamma (FGG) genes by PCR and conformation sensitive gel electrophoresis. Fourteen different disease‐causing mutations including frameshifts (51.9%), splice site (22.2%), missense (18.5%) and nonsense mutation (7.4%) were identified in 27 patients. Thirteen of them were novel, including seven frameshifts (fibrinogen Aα: p.Asp296 fs*59, p.Thr466 fs*17 and p.Lys575 fs*74; fibrinogen Bβ: p.Gly414 fs*2 and fibrinogen γ: p.Ser81 fs*5, p.Lys185 fs*13 and p.Asp278_279 fs*17), three splice site mutations (FGA gene c.364+1G>A; c.510+2 T>G; FGB gene c.851+1G>A), two missense substitutions (fibrinogen Bβ: p.Gly288Ser; p.Arg445Thr) and a nonsense mutation in fibrinogen Aα (p.Tyr127*). Two common mutations (FGA: c.364+1G>A, n = 6, FGG: p.Lys185 fs*13, n = 7) affecting 13 patients were identified in this series, suggesting that these mutations could be screened first in Indian patients with fibrinogen deficiency. The molecular data presented here is the largest series of patients with fibrinogen deficiency reported so far, adding significantly to the mutation database of this condition. It also helps create an algorithm for its genetic diagnosis in India.

Two novel missense mutations in iron transport protein transferrin causing hypochromic microcytic anaemia and haemosiderosis: molecular characterization and structural implications

This study was supported in part by a grant BT/PR-13968/MED/12/465/2010 from the Department of Biotechnology, Government of India to ES and by the grant SAF2012-40106 from the Spanish Secretary of Research, Development and Innovation (MINECO) and the grant CIVP16A1857 “Ayudas a proyectos de Investigacion en Ciencias de la Vida- Fundacion Ramon Areces” to M.S. M.S. held a research contract under the Ramon y Cajal program from the Spanish Ministry of Science and Innovation (RYC-2008-02352).

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.

Mean reticulocyte volume enhances the utility of red cell mean sphered cell volume in differentiating peripheral blood spherocytes of hereditary spherocytosis from other causes

CONTEXT Mean sphered cell volume (MSCV) and mean reticulocyte volume (MRV) are additional reticulocyte parameters generated while processing the blood samples on Beckman coulter LH 755 in the reticulocyte mode using the volume, conductivity and scatter technology. It has been observed that the difference between mean corpuscular volume (MCV) and MSCV is higher in the cases of hereditary spherocytosis (HS) and this difference is increasingly being utilized as a screening tool for spherocytes. In addition now there have been new observations that reticulocyte volume in cases of HS is less as compared to normal reticulocyte. AIMS Our aim was to test the usefulness of reticulocyte parameters like MSCV and MRV in distinguishing cases of HS and autoimmune hemolytic anemia (AIHA). MATERIALS AND METHODS This is a retrospective and partly prospective study where peripheral blood ethylenediaminetetraacetic acid samples from cases of HS (n = 57) and AIHA (n = 29) were processed on LH 755 in both the differential and the reticulocyte mode. The data generated were analyzed and compared with data from normal healthy donors (n = 46). RESULTS Using an algorithm of MCV - MSCV >10 and MRV - MSCV <25, a sensitivity of 84.2% and specificity of 94.7% was observed in cases of HS. CONCLUSIONS With the reticulocyte analysis, we may now have a simple and cheap additional tool for screening of HS.

Identification of rare and novel deletions that cause (δβ)0‐thalassaemia and hereditary persistence of foetal haemoglobin in Indian population

Hereditary persistence of foetal haemoglobin (HPFH) and (δβ)0‐thalassaemia are conditions caused by large deletions that involve δ‐ and β‐globin genes in the β‐globin cluster, and they are characterized by increased haemoglobin (HbF) levels in adults. Significant phenotypic diversity is observed between the different mutations that cause these conditions. Molecular characterization of these deletions is important for accurate molecular diagnosis, and they will also provide the information on the cis‐acting genetic regulatory elements present in the β‐globin cluster.

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.

Epidemiology of Non-Hodgkin's Lymphoma in India.

Non-Hodgkins lymphoma (NHL) is a common hematological malignancy. The age-adjusted incidence rates for NHL in men and women in India are 2.9/100,000 and 1.5/100,000, respectively. These are about one fourth of the incidence rates reported from Western Europe or North America. Within India, the incidence is several-fold higher in urban cancer registries compared to rural areas; the incidence being higher in metropolitan cities and Indian immigrants suggesting that urban lifestyles and economic progress may increase the cancer incidence. Compared to developed nations, the key differences in the presentation in India include: median age of 54 years (almost a decade less), higher male to female ratio, higher proportion of patients with B-symptoms (40-60 vs. 20-30%), poor ECOG performance status (≥2) at diagnosis (50 vs. 20-30%), higher frequency of diffuse large B-cell lymphomas (60-70 vs. <40%), lower frequency of follicular NHL (<20 vs. 30-40%) and T-cell type in 10-20 vs. <10%. The estimated mortality rate due to NHL is higher in India than in North America and Western Europe. Diagnostic and treatment delays, incorrect diagnosis and inappropriate or suboptimal treatment may be possible reasons for the poor outcome. Any improvement in the outcomes for NHL in India will require a nationwide approach, e.g. creation of several regional and district-level centers with expertise in lymphoma management. Collection of data on patient- and disease-related characteristics, treatment outcome, development of infrastructure, centralized review of histopathology subtype, novel treatment protocols, rigorous follow-up, training of staff, and financial support towards treatment could be possible strategies to improve the outcome.