Diffuse large B-cell lymphoma variants: an update Sukswai, Narittee; Lyapichev, Kirill; Khoury, Joseph D. ...
Pathology,
January 2020, 2020-Jan, 2020-01-00, 20200101, Letnik:
52, Številka:
1
Journal Article
Recenzirano
Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma, representing approximately one-third of all cases worldwide. In the World Health Organization (WHO) classification of ...lymphomas, most cases of DLBCL are designated as not otherwise specified (NOS). About 20% of cases, however, are designated as specific variants of DLBCL. These variants, 13 in total, are specified on the basis of distinctive morphological or immunophenotypic findings or distinctive biological or clinical issues associated with their diagnoses. In this review we discuss the following variants: T-cell/histiocyte-rich large B-cell lymphoma; ALK-positive large B-cell lymphoma; plasmablastic lymphoma; intravascular large B-cell lymphoma; large B-cell lymphoma with IRF4 rearrangement; primary mediastinal large B-cell lymphoma; primary cutaneous diffuse large B-cell lymphoma, leg type; primary diffuse large B-cell lymphoma of the central nervous system; diffuse large B-cell lymphoma associated with chronic inflammation; lymphomatoid granulomatosis; primary effusion lymphoma; and HHV8-positive diffuse large B-cell lymphoma, NOS. Two additional variants recognised in the WHO classification, EBV-positive diffuse large B-cell lymphoma and EBV-positive mucocutaneous ulcer are discussed elsewhere in another review within this issue of Pathology. Although not recognised as a specific variant in the current WHO classification, primary testicular diffuse large B-cell lymphoma also has unique biological features and requires some modification of the standard treatment approach for patients with DLBCL. Therefore, we suggest that primary testicular diffuse large B-cell lymphoma also should be recognised as a specific variant of DLBCL in a future version of the WHO classification.
Clonal cytogenetic evolution with additional chromosomal abnormalities (ACAs) in chronic myelogenous leukemia (CML) is generally associated with decreased response to tyrosine kinase inhibitor (TKI) ...therapy and adverse survival. Although ACAs are considered as a sign of disease progression and have been used as one of the criteria for accelerated phase, the differential prognostic impact of individual ACAs in CML is unknown, and a classification system to reflect such prognostic impact is lacking. In this study, we aimed to address these questions using a large cohort of CML patients treated in the era of TKIs. We focused on cases with single chromosomal changes at the time of ACA emergence and stratified the 6 most common ACAs into 2 groups: group 1 with a relatively good prognosis including trisomy 8, −Y, and an extra copy of Philadelphia chromosome; and group 2 with a relatively poor prognosis including i(17)(q10), −7/del7q, and 3q26.2 rearrangements. Patients in group 1 showed much better treatment response and survival than patients in group 2. When compared with cases with no ACAs, ACAs in group 2 conferred a worse survival irrelevant to the emergence phase and time. In contrast, ACAs in group 1 had no adverse impact on survival when they emerged from chronic phase or at the time of CML diagnosis. The concurrent presence of 2 or more ACAs conferred an inferior survival and can be categorized into the poor prognostic group.
•Based on their impact on treatment and survival, ACAs in CML were stratified into good and poor prognostic groups.•ACAs in the good prognostic group showed no adverse impact on survival when they emerged from chronic phase or at the initial CML diagnosis.
Summary Background Combination of chemotherapy with a tyrosine-kinase inhibitor is effective in the treatment of Philadelphia chromosome-positive acute lymphoblastic leukaemia. Ponatinib is a more ...potent BCR-ABL1 inhibitor than all other tyrosine-kinase inhibitors and selectively suppresses the resistant T315I clones. We examined the activity and safety of combining chemotherapy with ponatinib for patients with Philadelphia chromosome-positive acute lymphoblastic leukaemia in this continuing phase 2 trial. Methods In this single-centre, phase 2, single-arm trial, adult patients with previously untreated Philadelphia chromosome-positive acute lymphoblastic leukaemia were sequentially enrolled. Patients who had received fewer than two courses of previous chemotherapy with or without tyrosine-kinase inhibitors were also eligible. Patients had to be aged 18 years or older, have an Eastern Cooperative Oncology Group performance status of 2 or less, have normal cardiac function (defined by ejection fraction above 50%), and have adequate organ function (serum bilirubin ≤3·0 mg/dL and serum creatinine ≤3·0 mg/dL, unless higher concentrations were believed to be due to a tumour). Patients received eight cycles of hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (hyper-CVAD) alternating with high-dose methotrexate and cytarabine every 21 days. Ponatinib 45 mg was given daily for the first 14 days of cycle 1 then continuously for the subsequent cycles. Patients in complete remission received maintenance with ponatinib 45 mg daily with vincristine and prednisone monthly for 2 years followed by ponatinib indefinitely. The primary endpoint for this study was event-free survival. The trial is registered at ClinicalTrials.gov , number NCT01424982. Findings 37 patients were enrolled and treated from Nov 1, 2011, to Sept 1, 2013. 2-year event-free survival rate was 81% (95% CI 64–90). Grade 3 or more toxic effects included infections during induction (20 54% patients), increased aspartate aminotransferase and alanine aminotransferase concentration (14 38% patients), thrombotic events (three 8%), myocardial infarction (three 8%), hypertension (six 16%), skin rash (eight 22%), and pancreatitis (six 16% patients). Two patients died from from myocardial infarction potentially related to treatment; another patient also died from myocardial infarction related to sepsis. Two further patients died, one from bleeding and another from infection, both deemed unrelated to treatment. Interpretation The first results of this ongoing trial indicate that the combination of chemotherapy with ponatinib is effective in achieving early sustained remissions in patients with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukaemia. New strategies, including dosing titration of ponatinib and optimised control of vascular risk factors, might further improve outcomes. Funding ARIAD Pharmaceuticals Inc.
Purpose of Review
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignancy derived from plasmacyoid dendritic cells whose biology, clinical features, and treatment options are ...increasingly better understood.
Recent Findings
TCF4 is a master regulator that drives donwstream transcriptional programs in BPDCN. In turn, TCF4 activity is dependent on the bromodomain and extra-terminal domain (BET) protein BRD4 whose inhibition provides a promising therapeutic vulnerability. Notably, TCF4 expression is a highly sensitive marker for BPDCN and augments diagnostic specificity alongside CD4, CD56, CD123, and TCL1. The gene expression profile of BPDCN is characterized by aberrant NF-kappaB pathway activation, while its genomic landscape is dominated by structural chromosomal alterations involving
ETV6, MYC
, and
NR3C1,
as well as mutations in epigenetic regulators particularly
TET2
.
Summary
Advances in elucidating the biological characteristics of BPDCN are resulting in a more refined diagnostic approach and are opening novel therapeutic avenues for patients with this disease.
Purpose of Review
Immunohistochemistry is an integral technique for tissue-based diagnostics and biomarker detection with broad worldwide adoption. Advances in core chemistries, antibody design, and ...automation have ushered unprecedented sensitivity, specificity, and reproducibility in immunohistochemistry assays. As a result, clinical immunohistochemistry assays that utilize dual-color approaches and mutation-specific antibodies provide novel tools in clinical diagnostics that until recently were in the realm of investigational research. This review provides an overview of innovations in clinical immunohistochemistry assays with emphasis on those used for patients with hematopoietic neoplasms.
Recent Findings
Advances in clinical-grade immunohistochemistry techniques have allowed labs to develop and validate multiplex assays that improve diagnostic utility—such as CD5/PAX5 and TCF4/CD123 dual-color stains—and have the potential to enhance the specificity of biomarker detection. In addition, the increased availability of immunohistochemistry assays that detect mutant proteins (e.g., BRAF V600E and IDH1 R132H) provides a helpful replacement and/or adjunct for molecular testing. These techniques are highly reproducible, entail reasonable technical and interpretation complexity, and are relatively cost-effective, making them valuable novel tools in modern cancer care.
Summary
Multiplex and mutation-specific immunohistochemistry assays represent important innovations that provide improved utility in the context of personalized medicine and targeted therapy.
RUNX1 transcription factor regulates normal and malignant hematopoiesis. Somatic or germline mutant RUNX1 (mtRUNX1) is associated with poorer outcome in acute myeloid leukemia (AML). Knockdown or ...inhibition of RUNX1 induced more apoptosis of AML expressing mtRUNX1 versus wild-type RUNX1 and improved survival of mice engrafted with mtRUNX1-expressing AML. CRISPR/Cas9-mediated editing-out of RUNX1 enhancer (eR1) within its intragenic super-enhancer, or BET protein BRD4 depletion by short hairpin RNA, repressed RUNX1, inhibited cell growth, and induced cell lethality in AML cells expressing mtRUNX1. Moreover, treatment with BET protein inhibitor or degrader (BET–proteolysis targeting chimera) repressed RUNX1 and its targets, inducing apoptosis and improving survival of mice engrafted with AML expressing mtRUNX1. Library of Integrated Network–based Cellular Signatures 1000–connectivity mapping data sets queried with messenger RNA signature of RUNX1 knockdown identified novel expression-mimickers (EMs), which repressed RUNX1 and exerted in vitro and in vivo efficacy against AML cells expressing mtRUNX1. In addition, the EMs cinobufagin, anisomycin, and narciclasine induced more lethality in hematopoietic progenitor cells (HPCs) expressing germline mtRUNX1 from patients with AML compared with HPCs from patients with familial platelet disorder (FPD), or normal untransformed HPCs. These findings highlight novel therapeutic agents for AML expressing somatic or germline mtRUNX1.
•Depleting RUNX1 or editing-out RUNX1 eR1, or treatment with BET protein antagonist, induces lethality in AML expressing mtRUNX1.•EMs of RUNX1 depletion induce more lethality in HPCs expressing germline mtRUNX1 from FPD AML than HPCs from FPD.
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