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.

Fluorescence in situ hybridization: a highly efficient technique of molecular diagnosis and predication for disease course in patients with myeloid leukemias.

The accuracy of cytogenetic diagnosis in the management of hematological malignancies has improved significantly over the past 10 years. Fluorescence in situ hybridization (FISH), a technique of molecular cytogenetics, has played a pivotal role in the detection of unique sub-microscopic chromosomal rearrangements that helped in the identification of chromosomal loci, which contain genes involved in leukemogenesis. We studied the feasibility and sensitivity of the FISH technique for molecular analysis of translocations markers, t(9;22) and t(15;17) for accurate molecular diagnosis and for monitoring the disease in 21 patients with chronic myeloid leukemia (CML) who received interferon-alpha and/or chemotherapy (7 patients), bone marrow transplantation (14 patients), and 14 patients with acute promyelocytic leukemia (APL) who received all-trans-retinoic acid (ATRA) and/or chemotherapy. We also applied conventional karyotyping (CK) for identification of t(9;22) and t(15;17) at diagnosis. All CML cases had a Ph; t(9;22) and except for two cases all APL had t(15;17). The FISH studies on CML marrows in complete cytogenetic remission (CCR) (100% Ph- by CK) achieved by IFN-alpha, showed 0-2.5% of cells with BCR-ABL fusion in first cytogenetic remission (Controls, range 0.5-1.5%). Repeat follow-up FISH studies could be done in two cases in remission, which demonstrated 0-10% of cells with BCR-ABL fusion. Evaluation of Ph positive status of CML marrow at diagnosis by CK (100% Ph+ cells) and FISH (80-92% BCR-ABL fusion) pointed the existence of dormant clone of normal residual hematopoietic cells along with actively proliferating clones of Ph positive cells. Fluorescence in situ hybridization analysis of post-BMT CML marrows in CCR (0% Ph+ mitoses) could detect MRD with range of 1-6%. Among 14 patients, 9 who showed percentage of BCR-ABL positive cells (0.0-1.5%) almost similar to normal controls, 6 patients had comparatively good prognosis (disease-free survival 7-14 months). Of five patients with residual leukemic cells in the range of 2-6%, 4 relapsed within a period of 3-24 months. Fourteen APL patients in CCR [100% t(15;17) negative cells by CK] were evaluated by FISH to check the presence of residual leukemic cells. In these patients FISH could efficiently detect 1-14.5% of residual cells with PML-RARA (patients mean MRD 5%, controls mean MRD 3.5%, P=.02). Since the time of FISH analysis, 5 to 7 patients with higher fraction of leukemic cells (5-11%) relapsed within a short period (1-7 months). On the contrary, 5 of 7 patients with either absence or low percentage of PML-RARA positive cells remained in complete remission for 11-24 months. Our data show that FISH has a potential to detect and measure the fraction of aberrant malignant cells in remission marrows, induced by BMT in CML and chemotherapy in APL. These findings encourage the investigations on a large scale to merit its potential for identification of patients at high risk. In the present studies, FISH on interphase cells also demonstrated its efficiency in the molecular diagnosis by its ability to detect BCR-ABL and PML-RARA fusion in CML with masked/variant Ph and t(15;17) negative APL, respectively. The efficiency of technique in molecular diagnosis was also proved in one of the CML patients who progressed to myeloid blastic phase where interphase FISH could identify an extra BCR-ABL fusion on both chromosomes 9 indicating insertion of BCR into ABL and its duplication.

Trilateral retinoblastoma with an RB1 deletion inherited from a carrier mother: a case report.

A presentation of intracranial tumor in bilateral and unilateral retinoblastoma with or without family history is termed as trilateral retinoblastoma (TRB). It always occurs either as a pineal tumor or supra/parasellar tumor, which differ in presentation and prognosis. We report here the first case of TRB with transmission of retinoblastoma gene (RB1) deletion from an unaffected mother (a carrier), presenting as concurrent intracranial neoplasm with bilateral retinoblastoma. The presence of RB1 mutation in both child and mother could be responsible for development of intracranial neoplasm which occurred simultaneously with bilateral RB in our patient. Our patient, who had a suprasellar mass, received radiation and intrathecal chemotherapy, and died 6 months after diagnosis. The occurrence of intracranial tumor in an asymptomatic stage can be avoided by routine computed tomography (CT) and magnetic resonance imaging (MRI) scan, and improved survival can be achieved by aggressive multimodality therapy.

Clinical significance of cytogenetic findings at diagnosis and in remission in childhood and adult acute lymphoblastic leukemia: experience from India.

We report cytogenetic findings in 114 patients of acute lymphoblastic leukemia (ALL), which includes 78 children (< or = 15 years) and 36 adults (16-60 years). Chromosome aberrations were detected in 109 (95%) cases. A lower frequency of hyperdiploidy (15%) in children and a higher frequency of hypodiploidy both in children (38.4%) and adults (44.4%) were found, in contrast to literature. Translocations were detected in one third of adult and pediatric cases. The incidence of t(9;22) was comparatively low in adults (7.7%). Frequency of t(1:19) was also low in overall ALL cases. Various other recurrent abnormalities such as del(6q), abn(11q23), i(9p), abn(12q13), del(7q), and i(17q) were seen in our cases; a striking difference in the incidence of del(6q) (41%) and abn(11q23) (30%) was found in our series versus reported literature. Ploidy distribution indicated association of pseudo- and hypodiploidy with B-lineage, and hypodiploidy with T-lineage in children. The occurrence of del(6q) was more frequent in pediatric ALL with highly aberrant pattern and also with lymphadenopathy. Abn(11q23) was found to be early-B and pre-B specific. Kaplan-Meier analysis of overall survival revealed prognostic value of sex, FAB, immunophenotype, and cytogenetic findings. Females and T-ALL patients had a better prognosis, whereas males and B-ALL patients had poor outcome in overall and pediatric age groups. Prognostic evaluation of cytogenetics indicated translocations as an independent high-risk predictor in childhood (P < 0.008) and adult ALL (P < 0.01). Childhood ALL with t(8;14) and t(4;11) and adults with t(9;22) had poor survival. Cytogenetics of remission marrows demonstrated disappearance of abnormal clones in 31.4%, and expansion in normal clones in 50% of patients. Persistence of original clones and development of new clones were observed in 20% and 33% of patients, respectively; whereas karyotype evolution was identified in 10% of patients. The prognostic significance of cytogenetic findings at diagnosis, and differential cytogenetic response in so-called clinical remission in our study indicated the utmost need for more intensive therapy for eradication of resistant clones, and necessity of sequential cytogenetic follow-up in these patients for identification of minimal residual disease.

Translocation (11;14)(q13;q32) and overexpression of cyclin D1 protein in a CD23-positive low-grade B-cell neoplasm.

We describe a case of low-grade B-cell neoplasm with features overlapping between B-chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). The patient presented with a 10-year history of stable CLL without any treatment. The peripheral-blood picture was consistent with atypical mixed CLL (French-American-British criteria), whereas the lymph-node histology was more consistent with MCL. Neoplastic cells were strongly positive for surface immunoglobulin M, kappa, CD5, CD20, CD23, and cyclin D1. Expression of CD11c was weak. Translocation (11;14) and der(10)t(10;?)(p11;?) were the primary cytogenetic changes observed in both peripheral blood (47%) and lymph node (7%). Trisomy 12 was absent. Deletion 6q21 and rearrangements involving 1p/q, consistently associated with progression in lymphomas, also were noted in the peripheral blood but were nonclonal. The present case and similar cases with features overlapping between CLL and MCL most likely represent hybrids. In cases with features of typical CLL, t(11;14) is probably associated with gradual progression and may precede clinical and histologic transformation.

Cytogenetic studies in patients from India with T-acute lymphoblastic leukemia.

Cytogenetic analysis was performed in 30 patients with T cell acute lymphoblastic leukemia (11 adults, 19 children) at initial presentation and analysis was also repeated in clinical and hematological remission in 15 patients. At initial presentation, chromosomal abnormalities were detected in 27 cases (90%) and hypodiploidy was detected in 19 patients (63.3%), followed by pseudodiploidy in six patients (20%) and hyperdiploidy in two patients (6.6%). Other karyotypic abnormalities detected were deletion 6q (40%), deletion 11 q (16.6%), deletion 7q (10%), abnormalities of chromosome 9 in (13.3%) and translocation t(11;14)(p13;q11) in 6.6% and der(12)t(12;?)(p13;?) in (3.3%). In complete remission, nine out of 15 cases (60%) showed chromosomal aberrations. Original abnormalities were detected in two cases (13.3%) and new abnormalities were detected in seven cases (46.6%).