Development of an NPM1/MLF1 D-FISH probe set for the detection of t(3;5)(q25;q35) identified in patients with acute myeloid leukemia.

The t(3;5)(q25;q35) NPM1/MLF1 fusion has an incidence of approximately 0.5% in acute myeloid leukemia (AML) and has an intermediate prognosis at diagnosis. We have developed a dual-color, dual-fusion fluorescence in situ hybridization (D-FISH) assay to detect fusion of the MLF1 and NPM1 genes.

ALK-negative anaplastic large cell lymphoma is a genetically heterogeneous disease with widely disparate clinical outcomes.

Anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma (ALCL) is a CD30-positive T-cell non-Hodgkin lymphoma that morphologically resembles ALK-positive ALCL but lacks chromosomal rearrangements of the ALK gene. The genetic and clinical heterogeneity of ALK-negative ALCL has not been delineated. We performed immunohistochemistry and fluorescence in situ hybridization on 73 ALK-negative ALCLs and 32 ALK-positive ALCLs and evaluated the associations among pathology, genetics, and clinical outcome.

Mutations and thrombosis in essential thrombocythemia: prognostic interaction with age and thrombosis history.

Background: Vascular events in essential thrombocythemia (ET) are associated with advanced age and thrombosis history. Recent information suggests additional effect from the presence of specific mutations.

Objectives: To examine the influence of age and thrombosis history on the reported association between mutational status and thrombosis-free survival in ET.

Intralymphatic cutaneous anaplastic large cell lymphoma/lymphomatoid papulosis: expanding the spectrum of CD30-positive lymphoproliferative disorders.

Intravascular large B-cell lymphomas and EBV NK/T-cell lymphomas commonly follow an aggressive clinical course. We recently reported an entirely intravascular anaplastic large cell lymphoma (ALCL) in the skin with a surprisingly indolent clinical course; interestingly, this lymphoma involved the lymphatic rather than the blood vasculature. We hypothesized that intravascular skin-limited ALCL is distinct from aggressive systemic intravascular lymphomas in its intralymphatic localization and clinical course.

Type 1 versus Type 2 calreticulin mutations in essential thrombocythemia: a collaborative study of 1027 patients.

CALR (calreticulin) trails JAK2 as the second most mutated gene in essential thrombocythemia (ET). Mutant CALR in ET is a result of frameshift mutations, caused by exon 9 deletions or insertions; type-1, 52-bp deletion (p.L367fs*46), and type-2, 5-bp TTGTC insertion (p.

Prolonged administration of azacitidine with or without entinostat for myelodysplastic syndrome and acute myeloid leukemia with myelodysplasia-related changes: results of the US Leukemia Intergroup trial E1905.

Purpose: Although azacitidine (AZA) improves survival in patients with high-risk myelodysplastic syndrome, the overall response remains approximately 50%. Entinostat is a histone deacetylase inhibitor that has been combined with AZA with significant clinical activity in a previous phase I dose finding study.

Design: Open label phase II randomized trial comparing AZA 50 mg/m(2)/d given for 10 days ± entinostat 4 mg/m(2)/d day 3 and day 10.

Histiocytoid Sweet syndrome may indicate leukemia cutis: a novel application of fluorescence in situ hybridization.

Background: In patients with malignancy-associated Sweet syndrome, a thorough evaluation for leukemia cutis should be considered.

Objective: We sought to describe the clinicopathologic characteristics of histiocytoid Sweet syndrome.

Methods: We retrospectively identified patients with histiocytoid Sweet syndrome at our institution from January 1992 through December 2010.

Development of acute megakaryoblastic leukemia in Down syndrome is associated with sequential epigenetic changes.

Acute megakaryoblastic leukemia (AMKL) is more frequently observed in Down syndrome (DS) patients, in whom it is often preceded by a transient myeloproliferative disorder (TMD). The development of DS-TMD and DS-AMKL requires not only the presence of the trisomy 21 but also that of GATA1 mutations. Despite extensive studies into the genetics of DS-AMKL, the importance of epigenetic deregulation in this disease has been unexplored.

Clonally related follicular lymphomas and Langerhans cell neoplasms: expanding the spectrum of transdifferentiation.

The traditional model of hematopoiesis is based on unidirectional maturation of hematopoietic precursors into lineage-committed cells. However, recent studies indicate that mature B lymphocytes may demonstrate significant lineage plasticity. We and others have reported transdifferentiation of follicular lymphomas (FLs) into clonally related histiocytic/dendritic cell neoplasms.

Evaluation of revised IPSS cytogenetic risk stratification and prognostic impact of monosomal karyotype in 783 patients with primary myelodysplastic syndromes.

Cytogenetic classification by the revised international prognostic scoring system (IPSS-R) and the prognostic value of monosomal karyotype (MK) were assessed in 783 patients with primary myelodysplastic syndromes (MDS). At 22 months median follow-up, 562 (72%) deaths were recorded. Percentages of patients with IPSS-R "very good," "good," "intermediate," "poor," and "very poor" cytogenetic categories was 5, 63, 18, 4, and 10%, respectively.

Chromosomal rearrangements of 6p25.3 define a new subtype of lymphomatoid papulosis.

Lymphomatoid papulosis (LyP) is an indolent cutaneous lymphoproliferative disorder with clinical and pathologic features overlapping those of both reactive conditions and aggressive lymphomas. Recurrent genetic abnormalities in LyP have not been previously identified. Here, we describe the clinical, immunophenotypic, and genetic characteristics of cutaneous lymphoproliferative lesions showing distinctive and previously undescribed histologic features in 11 patients.

Differences in the distribution of cytogenetic subtypes between multiple myeloma patients with and without a family history of monoclonal gammopathy and multiple myeloma.

We previously reported an increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first-degree relatives of MGUS and multiple myeloma patients. Here, we examine whether primary cytogenetic categories of myeloma differ between patients with and without a family history of MGUS or myeloma. We studied 201 myeloma patients with available data on family history and molecular cytogenetic classification.

Atypical generalized eruptive histiocytosis clonally related to chronic myelomonocytic leukemia with loss of Y chromosome.

Generalized eruptive histiocytosis, described in 1963 by Winklemann and Muller, is a reactive, self-healing form of non-Langerhans histiocytosis. Rare cases of atypical generalized eruptive histiocytosis have been reported in patients with hematopoietic malignancy, but the biological relationship between the two disorders is not known. We report an 84-year-old man with chronic myelomonocytic leukemia who presented with coalescing erythematous papules and plaques on the posterior neck, ear and lower lip, followed by development of blast crisis.

t(8;9)(p22;p24)/PCM1-JAK2 activates SOCS2 and SOCS3 via STAT5.

Fusions of the tyrosine kinase domain of JAK2 with multiple partners occur in leukemia/lymphoma where they reportedly promote JAK2-oligomerization and autonomous signalling, Affected entities are promising candidates for therapy with JAK2 signalling inhibitors. While JAK2-translocations occur in myeloid, B-cell and T-cell lymphoid neoplasms, our findings suggest their incidence among the last group is low. Here we describe the genomic, transcriptional and signalling characteristics of PCM1-JAK2 formed by t(8;9)(p22;p24) in a trio of cell lines established at indolent (MAC-1) and aggressive (MAC-2A/2B) phases of a cutaneous T-cell lymphoma (CTCL).

Spliceosome mutations involving SRSF2, SF3B1, and U2AF35 in chronic myelomonocytic leukemia: prevalence, clinical correlates, and prognostic relevance.

SRSF2, SF3B1, and U2AF35 (U2AF1) are the three most frequent genes involved with spliceosome mutations in myeloid malignancies. SF3B1 mutations are most frequent (~80%) in myelodysplastic syndromes (MDS) with ring sideroblasts (RS) but lack prognostic relevance. SRSF2 mutations are associated with shortened overall (OS) and leukemia-free survival (LFS) in both MDS and myelofibrosis.

A case of nonleukemic myeloid sarcoma with FIP1L1-PDGFRA rearrangement: an unusual presentation of a rare disease.

Rearrangement of the PDGFRA gene defines a distinct group of hematopoietic neoplasms that commonly present with persistent eosinophilia and are highly sensitive to low-dose imatinib mesylate treatment. Although rare cases of PDGFRA rearrangement-associated acute myeloid or lymphoblastic leukemia can occur, nonleukemic myeloid sarcoma has not been reported, and its sensitivity to imatinib treatment is unknown. Herein, we report a 31-year-old man with nonleukemic myeloid sarcoma and marked peripheral blood and bone marrow eosinophilia.

Integrative epigenomic analysis identifies biomarkers and therapeutic targets in adult B-acute lymphoblastic leukemia.

Unlabelled: Genetic lesions such as BCR-ABL1, E2A-PBX1, and MLL rearrangements (MLLr) are associated with unfavorable outcomes in adult B-cell precursor acute lymphoblastic leukemia (B-ALL). Leukemia oncoproteins may directly or indirectly disrupt cytosine methylation patterning to mediate the malignant phenotype. We postulated that DNA methylation signatures in these aggressive B-ALLs would point toward disease mechanisms and useful biomarkers and therapeutic targets.

Cutaneous extramedullary plasmacytoma: clinical, prognostic, and interphase cytogenetic analysis.

Extramedullary plasmacytoma (EMP) of the skin is a rare indolent neoplasm that shares morphological and immunophenotypic features with plasma cell myeloma (PCM), but the molecular features that distinguish these two entities have not been defined. We reviewed the clinical characteristics, course, and molecular abnormalities in 7 cases of cutaneous EMP (cEMP); 2 patients had primary cEMP and 5 had secondary cEMP. Two patients died of progressive extramedullary plasmacytoma, 1 without PCM; 1 patient who had only a hyperdiploid clone, died within 17 months of the diagnosis of cEMP; and 3 died of PCM.

SRSF2 mutations in primary myelofibrosis: significant clustering with IDH mutations and independent association with inferior overall and leukemia-free survival.

Among spliceosome component mutations, those involving SF3B1 are most frequent in myelodysplastic syndromes with ring sideroblasts (MDS-RS; ∼ 75% incidence) and SRSF2 in chronic myelomonocytic leukemia (∼ 28% incidence). We recently reported on the lack of prognostic significance for SF3B1 mutations in both MDS-RS and primary myelofibrosis (PMF). In the current study, we examined the prevalence and prognostic relevance of SRSF2 mutations in PMF.

When are apparently non-clonal abnormalities in bone marrow chromosome studies actually clonal?

The observation of an apparently non-clonal abnormal cell in a cytogenetic study for a hematologic neoplasm opens the possibility of a small, or slowly proliferating, abnormal clone. Many laboratories analyze additional cells or reflex to fluorescence in situ hybridization (FISH) to evaluate this possibility further. In a retrospective study of 500 cases with a non-clonal abnormal cell identified in a 20-cell analysis, we found that the benefit of additional metaphase analysis was limited to specific categories of abnormal karyotypes, including those with a complex karyotype or a classic abnormality known to be a recurring finding in hematologic neoplasms, and excluding all other categories.

CD25 expression status improves prognostic risk classification in AML independent of established biomarkers: ECOG phase 3 trial, E1900.

We determined the prognostic relevance of CD25 (IL-2 receptor-α) expression in 657 patients (≤ 60 years) with de novo acute myeloid leukemia (AML) treated in the Eastern Cooperative Oncology Group trial, E1900. We identified CD25(POS) myeloblasts in 87 patients (13%), of whom 92% had intermediate-risk cytogenetics. CD25 expression correlated with expression of stem cell antigen CD123.

Genome-wide analysis reveals recurrent structural abnormalities of TP63 and other p53-related genes in peripheral T-cell lymphomas.

Peripheral T-cell lymphomas (PTCLs) are aggressive malignancies of mature T lymphocytes with 5-year overall survival rates of only ∼ 35%. Improvement in outcomes has been stymied by poor understanding of the genetics and molecular pathogenesis of PTCL, with a resulting paucity of molecular targets for therapy. We developed bioinformatic tools to identify chromosomal rearrangements using genome-wide, next-generation sequencing analysis of mate-pair DNA libraries and applied these tools to 16 PTCL patient tissue samples and 6 PTCL cell lines.

Treatment-influenced associations of PML-RARα mutations, FLT3 mutations, and additional chromosome abnormalities in relapsed acute promyelocytic leukemia.

Mutations in the all-trans retinoic acid (ATRA)-targeted ligand binding domain of PML-RARα (PRα/LBD+) have been implicated in the passive selection of ATRA-resistant acute promyelocytic leukemia clones leading to disease relapse. Among 45 relapse patients from the ATRA/chemotherapy arm of intergroup protocol C9710, 18 patients harbored PRα/LBD+ (40%), 7 of whom (39%) relapsed Off-ATRA selection pressure, suggesting a possible active role of PRα/LBD+. Of 41 relapse patients coanalyzed, 15 (37%) had FMS-related tyrosine kinase 3 internal tandem duplication mutations (FLT3-ITD+), which were differentially associated with PRα/LBD+ depending on ATRA treatment status at relapse: positively, On-ATRA; negatively, Off-ATRA.