Clinico-pathological impact of cytogenetic subgroups in B-cell chronic lymphocytic leukemia: Experience from India.

BACKGROUND: The present study of 238 B‑cell Chronic Lymphocytic Leukemia (B‑CLL) patients were undertaken to seek the prevalence and to evaluate clinico‑pathological significance of recurrent genetic abnormalities such as del(13q14.3), trisomy 12, del(11q22.3) (ATM), TP53 deletion, del(6q21) and IgH translocation/deletion. MATERIALS AND METHODS: We applied interphase – fluorescence in situ hybridization (FISH) on total 238 cases of B‑CLL. RESULTS: Our study disclosed 69% of patients with genetic aberrations such as 13q deletion (63%), trisomy 12 (28%), 11q deletion (18%), 6q21 deletion (11%) with comparatively higher frequency of TP53 deletion (22%). Deletion 13q displayed as a most frequent sole abnormality. In group with coexistence of ≥2 aberrations, 13q deletion was a major clone indicating del(13q) as a primary event followed by 11q deletion, TP53 deletion, trisomy 12, 6q deletion as secondary progressive events. In comparison with del(13q), trisomy 12, group with coexistence of ≥2 aberrations associated with poor risk factors such as hyperleukocytosis, advanced stage, and multiple nodes involvement. In a separate study of 116 patients, analysis of IgH abnormalities revealed either partial deletion (24%) or translocation (5%) and were associated with del(13q), trisomy 12, TP53 and ATM deletion. Two of 7 cases had t(14;18), one case had t(8;14), and four cases had other variant IgH translocation t(?;14). CONCLUSION: Detail characterization and clinical impact are necessary to ensure that IgH translocation positive CLL is a distinct pathological entity. Our data suggests that CLL with various cytogenetic subsets, group with coexistence of ≥2 aberrations seems to be a complex cytogenetic subset, needs more attention to understand biological significance and to seek clinical impact for better management of disease.

Systemic mastocytosis with associated acute myeloid leukemia with t (8; 21) (q22; q22).

Systemic mastocytosis with associated clonal hematological nonmast cell lineage disease (SM-AHNMD) is a subtype of mastocytosis associated commonly with myeloid neoplasms, Non-Hodgkin's lymphoma, or other hematological neoplasms. In these conditions, mastocytosis needs to be differentiated from mast cell hyperplasia or mast cell activation states. Neoplastic nature of mastocytosis is proved either by morphology, aberrant immunophenotype, or detection of point mutation at codon-816 of c-kit gene. This is a rare entity, even more so in pediatric population. Herein, we report a case of 14-year-old girl with SM associated with acute myeloid leukemia with maturation with t(8;21). Multifocal dense infiltrate of spindle-shaped mast cells on bone marrow aspirate and biopsy with coexpression of CD2 and CD25 by flow cytometric analysis proved the SM component at the time of diagnosis and persistence at post induction status also.

Role of RT-PCR and FISH in diagnosis and monitoring of acute promyelocytic leukemia.

Background: Patients with a presence of Promyelocytic Leukemia-Retinoic Acid Receptor Alpha (PML-RARA) genes rearrangement predict a favorable response to all-trans retinoic acid (ATRA), and a significant improvement in survival. Therefore, establishing the presence of PML-RARA rearrangement is important for optimal patient management. Aim: The objective of this study is to compare and assess the role of fluorescent in situ hybridization (FISH) and reverse transcriptase polymerase chain reaction (RT-PCR) in the diagnosis and long-term monitoring of Acute Promyelocytic Leukemia (APL). Materials and Methods: We compared 145 samples received at different interval of times to analyze the sensitivity of RT-PCR and FISH. Results: The failure rate for RT-PCR was 4% at baseline, 13% at induction, and 0% at the end of consolidation. And for FISH it was 8% at baseline, 38% at induction, and 66% at the end of consolidation. The predictive values of relapse in the patients who were positive and negative by RT-PCR, at the end of induction, were 60 % and 3%, respectively, and at end of consolidation it was 67 % and 4%, respectively. On the other hand the predictive values of relapse in patients who were positive and negative by FISH at end of induction were 57 % and 6%, respectively; while at end of consolidation it was 14% who were negative by FISH. Conclusion: Both RT-PCR and FISH are important for the diagnosis of APL cases, as both techniques complement each other in the absence or failure of any one of them. However, RT-PCR is more sensitive than FISH for the detection of minimal residual disease in the long-term monitoring of these patients. The present study shows that the predictive value of relapse is more associated with minimal residual disease (MRD) results by RT-PCR than that by FISH.

Clinico-hematological profile in biphenotypic acute leukemia.

BACKGROUND: We present a clinico-hematological profile and treatment outcome of Biphenotypic Acute Leukemia (BAL). AIM: Study incidence and subtypes of BAL, correlate with age, morphology, and cytogenetic findings and correlate the clinico-hematological data with the treatment response. St Jude's and the EGIL's criteria have been compared for their diagnostic and clinical relevance. MATERIAL AND METHODS: Diagnosis was based on WHO classification, including clinical details, morphology, cytochemistry, immunophenotyping, and molecular genetics. We included those cases, which fulfilled the European Group for the Immunological Characterization of Acute Leukemia's (EGIL's) scoring system criteria for the diagnosis of BAL, as per recommendation of the WHO classification. RESULTS: There were 32 patients diagnosed with BAL, based on EGIL's criteria. Incidence of BAL was 1.2%. B-Myeloid (14 cases) followed by T-Myeloid BAL (13 cases) were the commonest subtypes. Polymorphous population of blasts (16 cases) was commonly associated with T-Myeloid BAL (10 cases). BCR ABL fusion positivity was a common cytogenetic abnormality (seven cases). Fifteen patients received chemotherapy; eight achieved complete remission (CR) at the end of the induction period. CONCLUSIONS: Pediatric BAL and T-B lymphoid BAL have a better prognosis. A comprehensive panel of reagents is required, including cytoplasmic markers; to diagnose BAL. St Jude's criteria is a simple, easy, and cost-effective method to diagnose BAL. The outcome-related prognostic factors include age, HLA-DR, CD34 negativity, and subtype of BAL. BCR-ABL expression is an important prognostic factor, as these cases will be labeled as Chronic myeloid leukemia (CML) in blast crisis with biphenotypic expression and treated accordingly.