RESUMEN
BACKGROUND: BRAFV600E mutation has been reported as a unique genetic lesion of hairy cell leukemia (HCL), a subset of which lacks this lesion and shows adverse outcomes. AIMS: To determine the prevalence of BRAFV600E in HCL from our center and derive clinicopathological correlation, if any. MATERIALS AND METHODS: A 9-year retrospective analysis of 46 consecutive cases of HCL diagnosed on morphology and immunophenotyping was done. Stained smears were used as samples for amplification refractory mutation system polymerase-chain reaction using fluorescent primers for mutation detection. RESULTS: BRAFV600E mutation was detected in 41/46 patients (89.1%) while absent in control samples of chronic lymphocytic leukemia. Cases mimicking HCL-variant clinically or immunophenotypically too showed the presence of this mutation. HCL with mutated BRAF presented at a younger age. No statistical difference in blood counts, tumor load, and immunophenotype patterns existed among BRAF mutated and unmutated group. Nine patients (45%) with mutated BRAF had residual disease following treatment with cladribine. CONCLUSION: BRAFV600E mutation analysis has a definitive role in the diagnosis of HCL.
Asunto(s)
Leucemia de Células Pilosas/genética , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Adulto , Anciano , Cladribina/uso terapéutico , Femenino , Humanos , Inmunofenotipificación , Leucemia de Células Pilosas/patología , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
INTRODUCTION: Copy number alterations (CNA) have been described in childhood precursor B-lineage acute lymphoblastic leukemia (B-ALL) which in conjunction with chromosomal abnormalities drive leukemogenesis. There is no consensus on the clinical incorporation of CNA in B-ALL. An integrated genomic classification (IGC) has been proposed which includes CNA and cytogenetics. METHODS: We correlated this IGC with immunophenotypic minimal residual disease (MRD) as well as other standard criteria for 245 patients of B-ALL such as National Cancer Institute (NCI) risk, D+8 prednisolone response, cytogenetics, and ploidy status. RESULTS: MRD was detectable in 81 patients (33.1%). The most common abnormalities were seen in CDKN2A/B (25.7%) followed by PAX5(20%), ETV6(16.7%), IKZF1(15.5%), Rb1(5.3%), BTG (3.3%), EBF1(2.0%), and PAR1(0.8%). On integrating CNA into the IGC, 170 patients (69.4%) were classified into good genomic risk (GEN-GR) whereas 75 (30.6%) belonged to the poor genomic risk (GEN-PR) category. The IGC showed a significant correlation with MRD and NCI risk. The presence of CNA predicted MRD clearance in intermediate cytogenetics group. CONCLUSION: These data seem to indicate that in addition to cytogenetics, CNA should be incorporated into routine clinical testing and risk algorithms for B-ALL. The IGC is of prognostic relevance and offers an additional avenue for prognostication and risk-adapted therapy.
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Dosificación de Gen , Neoplasia Residual/diagnóstico , Patología Molecular/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neoplasia Residual/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologíaRESUMEN
We document the characteristics of BCR-ABL kinase domain mutations (KDM) in the largest study from India comprising of 385 patients and demonstrate that more than half (51.9%) of these patients have detectable abnormalities in the KD both in adult and in pediatric chronic myelogenous leukemia (CML). These comprise singly occurring missense mutations (25.5%), polyclonal/compound point mutations (4.9%), and insertions/deletions (29.6%). Missense mutations were most commonly seen in the imatinib-binding region followed by the P-loop. The commonest mutation in our dataset was T315I. Other common missense mutations were Y253H, M244V, and F317L. A high prevalence of BCR-ABL exon7 deletion (p.R362fs*) was also seen (25.5% of the entire cohort), whereas the 35bpintron-derived insertion/truncation mutation detected in 12 patients. In the pediatric age group, 58.8% of patients harbored missense mutations, polyclonal/compound mutations as well as insertions and deletions. We detected 11 novel mutations (seven missense mutations and four insertions/deletions).