Anaplastic large cell lymphoma: a flow cytometric analysis of 29 cases

The Difficulties and Ease of Diagnosing Anaplastic Large Cell Lymphomas on Cytology

Introduction and Objectives

Anaplastic large cell lymphoma (ALCL), a unique non-Hodgkin lymphoma (NHL), is a CD30-positive neoplasm of T-cell lineage. Its distinctive yet variable cytomorphology makes diagnosing fine needle aspiration cytology (FNAC) challenging. This study was undertaken to study the cytomorphology and the utility of immunocytochemical (ICC) stains on cytology in ALCL and to discuss their morphological differential diagnosis.

Materials and Methods

The present study was conducted in the Department of Pathology of a tertiary care center. A retrospective review was done from January 2017 to July 2022, and all histopathologically and immunohistochemically (IHC) diagnosed cases of ALCL were taken and correlated with the cytological diagnosis.

Results

Twenty-one cases of histopathology examination and IHC-proven cases of ALCL were retrieved from the departmental archives and reviewed. The ages ranged from 3 to 80 years (median age 28 years). Commonly noted cytomorphologic features included singly dispersed large pleomorphic cells, hallmark cells, and Reed-Sternberg-like cells. CD15, CD30, epithelial membrane antigen, and anaplastic lymphoma kinase-1 were some of the ICC stains used in this study. All 21 cases had cytology correlation. Fourteen cases had concordant cyto-histological correlation. Seven cases of histopathologically proven ALCL were reported as Hodgkin lymphoma (HL) in three, ALCL/anaplastic diffuse large B-cell lymphoma, HL/ALCL, poorly differentiated carcinoma, and NHL in one case each on cytology.

Conclusion

ALCL has a reasonably distinct cytomorphologic appearance and ICC staining pattern, and a careful interpretation of both helps arrive at a reliable FNAC diagnosis.

Erythroid side scatter: A parameter that improves diagnostic accuracy of flow cytometry myelodysplastic syndrome scoring

BACKGROUND

Flow cytometry immunophenotyping (FCM) is a benchmark test for integrated diagnosis of myelodysplastic syndromes (MDS). Our department's FCM-MDS-score follows international guidelines and additionally includes the maturing erythroid (mEry) side scatter (SSC)/lymphocyte SSC ratio (mErySSCr), often increased in MDS patients. A recent exploratory computational flow analysis study highlighted mErySSC as the top feature for separating MDS from non-MDS. Thus, we sought to systematically evaluate the diagnostic accuracy of mErySSCr in conventional diagnostic FCM as used currently in-house.

METHODS

Historical MDS (n = 93), chronic myelomonocytic leukemia (CMML; n = 27) and non-neoplastic cytopenia (n = 57) cohorts were created. Differences between these cohorts and LG-MDS entities were mapped and the mErySSCr cut-off was refined. Prospective bone marrows (n = 213) received for marrow failure work-up were used to determine the sensitivity and specificity of mErySSCr, both as a sole parameter and as a component of the MDS-score.

RESULTS

Low-grade (LG)-MDS mErySSCr differed more prominently from controls (p = <0.0001) than high-grade (HG)-MDS (p = 0.024). CMML and controls had a similar mErySSCr. As sole parameter, mErySSCr specificity was 91.1% (n = 112 non-MDS diagnoses) and sensitivity was 36% for LG-MDS (n = 36) and 25% for new HG-MDS diagnoses (n = 16). The specificity of the MDS-score was similar if mErySSCr was omitted (81.3% with and 82.1% without). The MDS-score sensitivity for new HG-MDS diagnoses and CMML (n = 17) was 100%, and was not affected by mErySSCr. The score sensitivity for LG-MDS however, dropped from 86.1% to 72.2% when mErySSCr was excluded.

CONCLUSION

mErySSCr increases the diagnostic accuracy of flow-based MDS scoring in our setting, particularly for LG-MDS.

How I Diagnose Mature T-Cell Proliferations by Flow Cytometry

OBJECTIVES

Mature T-cell neoplasms are a challenging area of diagnostic hematopathology. Flow cytometry has emerged as a useful technique for T-cell assessment.

METHODS

We discuss the application of flow cytometry to the evaluation of mature T-cell proliferations, to include illustrative cases, theoretical framework, detailed review of normal and reactive T-cell subsets, and examination of diagnostic pitfalls.

RESULTS

Immunophenotypic aberrancy can be construed as a direct expression of the neoplastic phenotype, in contrast to clonal expansion, which is seen in reactive and neoplastic T-cell proliferations. Major and minor T-cell subsets show characteristic patterns of antigen expression. Reactive states can manifest expansions of normal minor subsets and also show alterations of antigen expression on certain populations. However, some patterns of antigen expression are either never or very rarely encountered in reactive T cells. Flow cytometric tools are now available to directly assess clonality in specific T-cell populations. Technical and biological pitfalls may complicate the interpretation of T-cell flow cytometry.

CONCLUSIONS

Flow cytometry is a very useful tool in the diagnostic armamentarium for the assessment of mature T-cell proliferations, but it must be interpreted based on a thorough knowledge of the T-cell immune response, as well as an awareness of clinical context.

Flow Cytometric Findings in Primary Effusion Lymphoma: A Report of Two Cases

Primary effusion lymphoma (PEL) is a rare B-cell lymphoma that usually occurs in the setting of HIV infection, and it is associated with Human Herpesvirus-8 (HHV-8). Diagnosis of PEL is usually established in cell centrifuge, cell block, or tissue examination, and there are few reports describing flow cytometry findings in PEL. We report two male patients (a 34-year-old and a 56-year-old) with a history of HIV infection. The first patient presented with ascites and abdominal pain, and the second patient presented with chest pain and parapneumonic pleural effusion. Cavitary fluid examination showed large pleomorphic neoplastic lymphoid cells with plasmablastic morphology. Flow cytometry analysis of the neoplastic lymphocytes showed increased forward scatter and side scatter with intermediate to a high level of CD38 expression. In one patient, lymphoma cells showed bright CD45 expression with dim expression of CD19 and kappa light chain. There was no significant expression of CD20 or any T/NK cell markers in either case. Immunohistochemistry for CD30 was positive in one patient. Immunohistochemistry for HHV-8 and in situ hybridization for Epstein-Barr virus-encoded small RNAs (EBER) was positive on cell blocks in both cases, consistent with the diagnosis of primary effusion lymphoma. PEL should be considered in the differential diagnosis of CD20-negative hematopoietic neoplasms, and flow cytometry may provide helpful clues for the diagnosis of PEL as part of the workup for pleural effusion with cytologically malignant cells.

Tissue Expander-associated T Cells: Relevance to Breast Implant-associated Anaplastic Large-cell Lymphoma

The generation of breast implant–associated anaplastic large-cell lymphoma (BIA-ALCL) is closely associated with textured implants. The phenotype of BIA-ALCL cells is well examined, but its cell of origin remains unknown. Here we investigate what types of T cells are recruited and differentiated in the surrounding capsules and tissues as a consequence of continuous contact with a textured surface.

BIA-ALCL diagnosis on CytoLyt fixed ThinPrep, cell block and immunohistochemistry

Breast implant associated anaplastic large cell lymphoma (BIA-ALCL) is an emergent rare T cell non-Hodgkin lymphoma arising in association with a breast implant, particularly textured ones. Recent guidelines list cytopathological examination as the first essential step for diagnosis, routinely followed by CD30 immunohistochemistry (IHC) and flow cytometry (FC) for a T cell clone. The majority of BIA-ALCL literature regarding cytopathological evaluation describes morphology based on various preparation methods limited to cytospins and smears with the exception of at least one case report detailing cytomorphological and IHC findings on ThinPrep. This case report details initial diagnosis of BIA-ALCL rendered with CytoLyt prepared ThinPrep and cell block, including the specific antibodies used for IHC. The ThinPrep slide showed numerous singly dispersed large, atypical cells with abundant cytoplasm containing irregular nuclei with dispersed chromatin and prominent nucleoli in a background of macrophages, inflammatory cells and granular debris. TIA-1 and CD30 along with other T-cell markers, including specific antibodies, remains immunoreactive in tissue collected in CytoLyt solution. Cell size reduction, artifactual lymphoid cell aggregation and prominent nucleoli in benign and reactive conditions are among other ThinPrep cellular alterations pathologists should bear in mind.

Immunophenotypic shifts during minimal residual evaluation in a case of leukemic form of anaplastic large cell lymphoma ALK

BACKGROUND

This study aims to describe immunophenotypic explorations at diagnosis and follow up of a pediatric patient with leukemic phase of ALK+ anaplastic large cell lymphoma (ALCL) by multiparametric flow cytometry (MFC).

CASE

An 8-color MFC combination of antibodies allowed to identify neoplastic cells in concentrations until 0.02% during minimal residual disease (MRD) monitoring. Immunophenotypic shifts occurred in key markers as CD30, CD7, CD2, and CD5, however neoplastic cells were clearly discriminated from normal populations.

CONCLUSION

MFC can be a useful tool for ALCL diagnosis and MRD monitoring and may support therapeutic decisions.

Diagnosis of the leukemic phase of ALK-positive anaplastic large cell lymphoma by immunohistochemistry on cell block prepared from peripheral blood buffy coat

A leukemic phase of anaplastic lymphoma kinase positive anaplastic large cell lymphoma (ALK+ ALCL) is rare. The leukemic cells morphologically appear as small to intermediate-sized cells with cerebriform and cloverleaf-like nuclei and are misdiagnosed as other T-Cell lymphomas/leukemia with similar morphology. We describe a case where the diagnosis of leukemic ALK+ ALCL was aided by immunohistochemistry performed on the cell blocks prepared from the peripheral blood buffy coat specimen. The diagnosis of ALK+ ALCL was further confirmed on the biopsy of a cutaneous nodule of this patient. We found the method of immunohistochemistry on peripheral blood buffy coat cell block very useful and suggest that it may be used as an alternative method to flowcytometry in low resource settings.

Practical Approaches on CD30 Detection and Reporting in Lymphoma Diagnosis

While our understanding of the biology of CD30 in lymphoma continues to evolve, our need to detect and measure its expression at the protein level remains critically important for diagnosis and patient care. In addition to its diagnostic and prognostic utility, CD30 has emerged as a vehicle for drug targeting through the antibody-drug conjugate brentuximab-vedotin (BV). Given the numerous ways that CD30 is utilized and its emergence as a predictive/prognostic biomarker, pathologists must come to a general consensus on the best reporting structure and methodology to ensure appropriate patient care. In this manuscript, we review the indications for testing, various modalities for testing, technical challenges, pitfalls, and potential standards of reporting. The following questions will try to be addressed in the current review article: What defines a "POSITIVE" level of CD30 expression?; How do we evaluate and report CD30 expression?; What are the caveats in the evaluation of CD30 expression?

Breast implant-associated anaplastic large cell lymphoma and effusions: A review with emphasis on the role of cytopathology

Breast implants are surgically implanted by the hundreds of thousands every year worldwide for reconstructive or aesthetic purposes. Complications related to breast implants include early and late effusions that are often submitted for cytopathological analysis, particularly to exclude the possibility of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), a rare disease that generally follows an indolent clinical course, although it is becoming clearer that a subset of patients with adverse features have a poorer prognosis. Since a late-onset breast implant-associated effusion is the most common initial presentation of BIA-ALCL, cytopathological analysis of these effusions is considered the cornerstone and gold standard for rapid, efficient, reliable diagnosis and is critical for appropriate management and treatment. The National Comprehensive Cancer Network recently published clinical guidelines for the diagnosis and management of BIA-ALCL and stresses the essential role of cytopathological analysis, although it remains a matter of debate if all seromas should undergo immunocytochemistry or flow cytometry, particularly for assessment of expression of CD30 irrespective of morphological appearance on cytology. Herein, we review the current knowledge on BIA-ALCL, review the key cytological findings of reactive and malignant effusions related to breast implants, and present a comprehensive cytopathological workup with the presence of atypical cells as the key and pivotal element triggering further ancillary studies. We believe this approach will ensure appropriate and cost-effective management of effusion specimens from breast implants.

Cell of Origin and Immunologic Events in the Pathogenesis of Breast Implant-Associated Anaplastic Large-Cell Lymphoma

Breast implant–associated anaplastic large-cell lymphoma (BIA-ALCL) is a CD30-positive, anaplastic lymphoma kinase–negative T-cell lymphoma. Nearly all cases have been associated with textured implants. Most cases are of effusion-limited, indolent disease, with an excellent prognosis after implant and capsule removal. However, capsular invasion and tumor mass have a more aggressive course and a fatal outcome risk. This review summarizes the current knowledge on BIA-ALCL cell of origin and immunologic factors underlying its pathogenesis. Cytokine expression profiling of BIA-ALCL cell lines and clinical specimens reveals a predominantly type 17 helper T-cell (Th17)/Th1 signature, implicating this as its cell of origin. However, a Th2 allergic inflammatory response is suggested by the presence of IL-13, with infiltration of eosinophils and IgE-coated mast cells in clinical specimens of BIA-ALCL. The microenvironment-induced T-cell plasticity, a factor increasingly appreciated, may partially explain these divergent results. Mutations resulting in constitutive Janus kinase (JAK)–STAT activation have been detected and associated with BIA-ALCL pathogenesis in a small number of cases. One possible scenario is that an inflammatory microenvironment stimulates an immune response, followed by polyclonal expansion of Th17/Th1 cell subsets with release of inflammatory cytokines and chemokines and accumulation of seroma. JAK-STAT3 gain-of-function mutations within this pathway and others may subsequently lead to monoclonal T-cell proliferation and clinical BIA-ALCL. Current research suggests that therapies targeting JAK proteins warrant investigation in BIA-ALCL.

Integration of transcriptional and mutational data simplifies the stratification of peripheral T-cell lymphoma

The histological diagnosis of peripheral T-cell lymphoma (PTCL) can represent a challenge, particularly in the case of closely related entities such as angioimmunoblastic T-lymphoma (AITL), PTCL-not otherwise specified (PTCL-NOS), and ALK-negative anaplastic large-cell lymphoma (ALCL). Although gene expression profiling and next generations sequencing have been proven to define specific features recurrently associated with distinct entities, genomic-based stratifications have not yet led to definitive diagnostic criteria and/or entered into the routine clinical practice. Herein, to improve the current molecular classification between AITL and PTCL-NOS, we analyzed the transcriptional profiles from 503 PTCLs stratified according to their molecular configuration and integrated them with genomic data of recurrently mutated genes (RHOA ^G17V , TET2, IDH2 ^R172 , and DNMT3A) in 53 cases (39 AITLs and 14 PTCL-NOSs) included in the series. Our analysis unraveled that the mutational status of RHOA ^G17V , TET2, and DNMT3A poorly correlated, individually, with peculiar transcriptional fingerprints. Conversely, in IDH2 ^R172 samples a strong transcriptional signature was identified that could act as a surrogate for mutational status. The integrated analysis of clinical, mutational, and molecular data led to a simplified 19-gene signature that retains high accuracy in differentiating the main nodal PTCL entities. The expression levels of those genes were confirmed in an independent cohort profiled by RNA-sequencing.

Role of Ancillary Techniques in Fluid Cytology

The cytologic evaluation of serous effusions may be challenging for a number of reasons. Distinction of benign, reactive conditions from malignancy represents the main focus when examining these specimens. The morphologic diagnosis of malignancy may be difficult due to the relative paucity of abnormal cells. In other situations, cellularity is not an issue, but the ability to confidently identify a second, foreign (i.e., tumor) population within a background mesothelial cells on the basis of cytomorphologic features alone may pose problems. Cases with definitive morphologic evidence of malignancy may require additional studies in order to determine the tumor subtype and, in the case of carcinoma, the primary site of origin. Cases in which a definitive and precise diagnosis of malignancy is made may be optimal candidates for further molecular testing in order to gain prognostic information and guide personal therapeutic decisions. Finally, while an inflammatory or infectious condition can be suggested on the basis of cellular components and associated background elements, the identification of causative agent(s) may be difficult without additional studies. In all of these situations, the use of ancillary studies and techniques is critical; their utility and appropriate application are the subject of this review.

Flow Cytometry Applications in the Diagnosis of T/NK-Cell Lymphoproliferative Disorders

This article provides an overview of the role of flow cytometry in the diagnosis, prognosis, and follow-up of T and NK-cell lymphoproliferative disorders. For each category, we will briefly discuss the immunophenotypic features of normal T and NK cells, and address technical issues in flow cytometry, the approach to diagnosis in various contexts, pitfalls in interpretation, and its use in follow-up and post-therapy management. In addition to reviewing the diagnostic, prognostic, and therapeutic utility of flow cytometric immunophenotyping in several of specific T and NK cell entities, we will also cover some of the new immunophenotypic markers. Furthermore, we will touch upon incorporation of flow cytometry in the final diagnosis, including correlation with other ancillary tests. © 2019 International Clinical Cytometry Society.

Diagnostic role of cytology in serous effusions of patients with hematologic malignancies

BACKGROUND

We investigated serous effusions occurring during the course of an already known hematologic neoplasia or as a first manifestation of it. We correlated cytology results with flow cytometry results, when available. In the absence of flow cytometry, our correlation was based on clinical follow up information obtained retrospectively. We evaluated our results in relation to the data of the literature and we considered some new suggestions for the improvement of cytology service.

METHODS

Serous effusions in hematologic patients were retrieved from the files of the Department of Cytology, Laiko Hospital, for a period of 2 years. All patients had enrolled either a previous hematologic history, or a suspicious clinical and imaging status. Seventy-three serous effusions were included. Cytology reports consisting of morphology and immunocytochemistry assessment were correlated to flow cytometry results and, occasionally, to clinical follow-up.

RESULTS

In the group of patients with previous history, sensitivity was 82.76%, positive predictive value was 100%, specificity 100%, and negative predictive value was 58.33%. In the group of patients without previous history, sensitivity and positive predictive value were both 91%, whereas specificity and negative predictive value could not be estimated.

CONCLUSION

We provide evidence that the diagnostic accuracy of cytology with the adjunct of immunocytochemistry is high compared to flow cytometry for detecting hematologic malignancies. In order to improve clinical performance, it is suggested that a cytology triage of serous effusions in all patients with hematologic malignancy must be implemented.

Flow Cytometry and Effusions in Lymphoproliferative Processes and Other Hematologic Neoplasias

Cytopathologists are regularly confronted with lymphocyte-rich effusions, and the definite decision of whether the lymphocytosis is of a purely reactive nature or a presentation of an indolent lymphoma may be an extremely difficult one based on microscopy alone. Flow cytometry (FC) offers many advantages in terms of its application in body cavity fluids, and it has proven to be very useful both in the setting of a known disease and for new lymphoma diagnoses. In this paper, the studies published in recent years dealing with the applications of FC in body cavity effusions in the context of hematologic neoplasia are reviewed, stressing the integrative diagnostic approach. The incorporation of microscopical, immunophenotypical, and molecular findings from examinations of the cellular content of effusions and the interpretation of results in relation to the current WHO classification of hematolymphoid malignancies give cytopathologists new perspectives on advanced and clinically highly relevant diagnostics.

Diagnosis of chronic lymphoproliferative disorders by flow cytometry using four-color combinations for immunophenotyping: A proposal of the brazilian group of flow cytometry (GBCFLUX)

BACKGROUND

Multiparametric flow cytometry (MFC) is a powerful tool for the diagnosis of hematological malignancies and has been useful for the classification of chronic lymphoproliferative disorders (CLPD) according to the WHO criteria. Following the purposes of the Brazilian Group of Flow Cytometry (GBCFLUX), the aim of this report was to standardize the minimum requirements to achieve an accurate diagnosis in CLPDs, considering the different economic possibilities of the laboratories in our country. Most laboratories in Brazil work with 4-fluorescence flow cytometers, which is why the GBCFLUX CLPD Committee has proposed 4-color monoclonal antibody (MoAb) panels.

METHODS/RESULTS

Panels for screening and diagnosis in B, T and NK lymphoproliferative disorders were developed based on the normal differentiation pathways of these cells and the most frequent phenotypic aberrations. Important markers for prognosis and for minimal residual disease (MRD) evaluation were also included. The MoAb panels presented here were designed based on the diagnostic expertise of the participating laboratories and an extensive literature review.

CONCLUSION

The 4-color panels presented to aid in the diagnosis of lymphoproliferative neoplasms by GBCFLUX aim to provide clinical laboratories with a systematic, step-wise, cost-effective, and reproducible approach to obtain an accurate immunophenotypic diagnosis of the most frequent of these disorders. © 2016 International Clinical Cytometry Society.

In vitro and in vivo activity of melflufen (J1)in lymphoma

BACKGROUND

Melphalan has been used in the treatment of various hematologic malignancies for almost 60 years. Today it is part of standard therapy for multiple myeloma and also as part of myeloablative regimens in association with autologous allogenic stem cell transplantation. Melflufen (melphalan flufenamide ethyl ester, previously called J1) is an optimized derivative of melphalan providing targeted delivery of active metabolites to cells expressing aminopeptidases. The activity of melflufen has compared favorably with that of melphalan in a series of in vitro and in vivo experiments performed preferentially on different solid tumor models and multiple myeloma. Melflufen is currently being evaluated in a clinical phase I/II trial in relapsed or relapsed and refractory multiple myeloma.

METHODS

Cytotoxicity of melflufen was assayed in lymphoma cell lines and in primary tumor cells with the Fluorometric Microculture Cytotoxicity Assay and cell cycle analyses was performed in two of the cell lines. Melflufen was also investigated in a xenograft model with subcutaneous lymphoma cells inoculated in mice.

RESULTS

Melflufen showed activity with cytotoxic IC50-values in the submicromolar range (0.011-0.92 μM) in the cell lines, corresponding to a mean of 49-fold superiority (p < 0.001) in potency vs. melphalan. In the primary cultures melflufen yielded slightly lower IC50-values (2.7 nM to 0.55 μM) and an increased ratio vs. melphalan (range 13-455, average 108, p < 0.001). Treated cell lines exhibited a clear accumulation in the G2/M-phase of the cell cycle. Melflufen also showed significant activity and no, or minimal side effects in the xenografted animals.

CONCLUSION

This study confirms previous reports of a targeting related potency superiority of melflufen compared to that of melphalan. Melflufen was active in cell lines and primary cultures of lymphoma cells, as well as in a xenograft model in mice and appears to be a candidate for further evaluation in the treatment of this group of malignant diseases.

Flow cytometric immunophenotyping and cell block immunocytochemistry in the diagnosis of primary Non-Hodgkin's Lymphoma by fine-needle aspiration: Experience from a tertiary care center

Background:

Accurate diagnosis of Non-Hodgkin's Lymphoma (NHL) on fine-needle aspiration (FNA) specimen is challenging and requires ancillary testing.

Aim:

The feasibility of flow cytometric immunophenotyping (FCI) along with cell block immunocytochemistry (CB-ICC) as adjunct techniques in the diagnosis of NHL as per the current World Health Organization (WHO) classification was evaluated.

Materials and Methods:

All cases of suspected lymphoma underwent FNA, and the sample was triaged for light microscopic evaluation, FCI, and CB-ICC, and each case was classified as per the current WHO classification.

Results:

A total of 65 cases was analyzed which included 40 B-cell, 21 T-cell, and 4 unclassifiable lymphomas. Of 61 cases, FCI alone was contributory in 74% (45/61) cases whereas CB-ICC alone was contributory in 65.5% (40/61) cases in typing the lymphoma. In 11.4% (7/61) cases, the lymphoma could not be classified by either technique. Thus, in a total of 88.5% (54/61) cases a combination of FCI and CB-ICC from FNA enabled a diagnosis of lymphoma with its subtyping.

Conclusion:

Flow cytometric immunophenotyping and ICC on CBs are feasible on FNA material and are very useful in a suspected case of NHL especially when a biopsy may not be possible or feasible.

Biomarkers in childhood non-Hodgkin's lymphomas

Pediatric non-Hodgkin's lymphomas (NHLs) are a heterogeneous group of malignancies with distinct clinical, pathological, immunological and genetic characteristics. More than 90% of pediatric NHLs belong to one of three major histological subtypes: mature B-cell neoplasms, lymphoblastic lymphomas and anaplastic large-cell lymphomas. The recognition that different subtypes require different treatment regimens resulted in therapeutic strategies leading to over 80% of patients being cured. On the other hand, patients with resistant or relapsed disease have a poor prognosis. Prognostic biomarkers have not yet been identified for all pediatric NHLs and, although some are very important for diagnosis and prognosis, others may be of questionable value. Discovery of new biomarkers suitable for clinical application may aid the diagnosis and classification of lymphomas, which should, in turn, lead to better patient stratification. Consequent development of new treatment and follow-up approaches should lead to more efficient and less toxic treatment in children with NHL.

CLTC-ALK fusion as a primary event in congenital blastic plasmacytoid dendritic cell neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a subtype of acute myeloid leukemia, affecting mainly the elderly. It is thought to be derived from plasmacytoid dendritic cell precursors, which frequently present as cutaneous lesions. We have made a detailed analysis of an infant with BPDCN, who manifested with hemophagocytic lymphohistiocytosis. The peripheral blood leukocytes revealed the t(2;17;8)(p23;q23;p23) translocation and a CLTC-ALK fusion gene, which have never been reported in BPDCN or in any myeloid malignancies thus far. Neonatal blood spots on the patient's Guthrie card were analyzed for the presence of the CLTC-ALK fusion gene, identifying the in utero origin of the leukemic cell. Although the leukemic cells were positive for CD4, CD56, CD123, and CD303, indicating a plasmacytoid dendritic cell phenotype, detailed analysis of the lineage distribution of CLTC-ALK revealed that part of monocytes, neutrophils, and T cells possessed the fusion gene and were involved in the leukemic clone. These results indicated that leukemic cells with CLTC-ALK originated in a multipotent hematopoietic progenitor in utero. This is the first report of the CLTC-ALK fusion gene being associated with a myeloid malignancy, which may give us an important clue to the origin of this rare neoplasm.

Simultaneous cytomorphological and multiparameter flow cytometric analysis of ALK-positive anaplastic large cell lymphoma in children

The aim of this study was to investigate the pathological features of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) in children and to establish the effectiveness of screening and diagnosing ALCL with multiparameter flow cytometry immunophenotyping (FCI) of lymphoid tissue samples. A total of 121 lymph node tissue specimens obtained from 121 patients with a suspected diagnosis of lymphoma were analyzed with cytomorphological and FCI analysis. Fifteen cases were diagnosed as ALK-positive ALCL based on the pathological features and immunohistochemical results. Of these, there were 3 different types, common type (10 cases), lymphohistiocytic type (4 cases) and neutrophil-rich type (1 case). Thirteen cases (10 common, 2 lymphohistiocytic and 1 neutrophil-rich type) were diagnosed as ALCL using FCI. These cases were CD30-positive and aberrantly expressed at least two T-cell antigens, including CD4 (84.6%), CD2 (76.9%), CD7 (61.5%), CD3 (53.8%) and CD5 (38.4%). Neoplastic cells accounted for only a small proportion of the total cells in FCI, with a median of 19.3% (range, 7.9-31.8%), which was significantly higher than those in the control groups (all <1.0%). The sensitivity of FCI for diagnosing ALCL in lymph node samples was 86.7% with a specificity of 100%. The majority of neoplastic cells demonstrated high light forward and high light side scatter, similar to monocytes or granulocytes in dot plots. FCI may be used as an adjunct to histopathological examination for rapid and reliable diagnosis of pediatric ALCL. Flexible gating strategies and careful analysis are required to identify neoplastic cells with FCI.

Anaplastic large cell lymphoma: an unusual presentation in a 7-year-old girl

Anaplastic large cell lymphoma (ALCL) accounts for 10% to 30% of all childhood lymphomas and approximately 5% of all non-Hodgkin's lymphoma. ALCL is considered to be a T-cell non-Hodgkin's lymphoma that can be divided into two major groups with distinct genetic, immunophenotypic, and clinical behaviors. The first group consists of a spectrum of CD30+ T-cell lymphoproliferative disorders that include primary cutaneous ALCL (C-ALCL) and lymphomatoid papulosis. The second group is systemic ALCL (S-ALCL), which is further divided into two subgroups: anaplastic lymphoma kinase positive (ALK+) and ALK-negative. Between 30% and 60% of S-ALCL express ALK, which is usually the result of a t(2;5) translocation that correlates with onset in the first three decades of life, male predominance, and good prognosis. Although morphologically similar, ALK- ALCL shows varied clinical behaviors and immunophenotypes; is commonly seen in older age groups, with a peak incidence in the sixth decade of life with no preference as to sex; and has an overall poorer prognosis. We present a case of CD30+, ALK- S-ALCL in a 7-year-old girl.

Leukemic presentation of ALK-negative anaplastic large cell lymphoma in a patient with myelodysplastic syndrome

A 50-year-old woman with a history of aplastic anemia developed cervical lymphadenopathy and atypical lymphocytosis. Atypical cells of lymph nodes were positive for CD3 and CD30 but negative for anaplastic lymphoma kinase (ALK). Bone marrow examination showed trilineage myelodysplasia. She was diagnosed with ALK-negative anaplastic large cell lymphoma (ALCL) with leukemic transformation and myelodysplastic syndrome (MDS) which presumably developed from aplastic anemia. The lymphoma was resistant to intensive chemotherapies, ultimately leading to death. Leukemic presentation of ALK-negative ALCL as an initial manifestation is extremely rare, and the progression of the disease may be influenced by MDS through alteration of immune functions.

Anaplastic large cell lymphoma: twenty-five years of discovery

CONTEXT

The year 2010 commemorates the 25th year since the seminal publication by Karl Lennert and Harald Stein and others in Kiel, West Germany, describing an unusual large cell lymphoma now known as anaplastic large cell lymphoma (ALCL). Investigators at many universities and hospitals worldwide have contributed to our current in-depth understanding of this unique peripheral T-cell lymphoma, which in its systemic form, principally occurs in children and young adults.

OBJECTIVE

To summarize our current knowledge of the clinical and pathologic features of systemic and primary cutaneous ALCL. Particular emphasis is given to the biology and pathogenesis of ALCL.

DATA SOURCES

Search of the medical literature (Ovid MEDLINE In-Process & Other Non-Indexed Citations and Ovid MEDLINE: 1950 to Present [National Library of Medicine]) and more than 20 years of diagnostic experience were used as the source of data for review.

CONCLUSIONS

Based on immunostaining for activation antigen CD30 and the presence of dysregulation of the anaplastic lymphoma kinase gene (2p23), the diagnosis of ALCL has become relatively straightforward for most patients. Major strides have been made during the last decade in our understanding of the complex pathogenesis of ALCL. Constitutive NPM-ALK signaling has been shown to drive oncogenesis via an intricate network of redundant and interacting pathways that regulate cell proliferation, cell fate, and cytoskeletal modeling. Nevertheless, pathomechanistic, therapeutic, and diagnostic challenges remain that should be resolved as we embark on the next generation of discovery.

Erythroblastic sarcoma presenting as bilateral ovarian masses in an infant with pure erythroid leukemia

Pure erythroid leukemia is a rare subtype of acute erythroid leukemia that is characterized by a predominant erythroid population, and erythroblastic sarcoma has not yet been described in the English literature. Here, we report a first case of erythroblastic sarcoma that presented as bilateral ovarian masses in a 3 ½-month-old infant girl with pure erythroid leukemia. Bone marrow aspirate and biopsy showed that the marrow was completely replaced by large-sized blasts consistent with erythroblasts. Immunophenotypically, both the tumor cells from the ovarian mass and bone marrow blasts were positive for CD117, glycophorin A, and hemoglobin A, demonstrating erythroid differentiation. Reverse transcriptase polymerase chain reaction showed that the tumor cells from ovarian mass expressed hemoglobin F and α1 spectrin, confirming their erythroid lineage. Conventional karyotype of the bone marrow aspirates revealed del(6)(q23q25) and trisomy 7 in all 21 cells examined. Fluorescence in situ hybridization of the ovarian mass demonstrated loss of c-myeloblastosis viral oncogene (C-MYB) at 6q23 locus in 41% of the cells, and deletion of chromosome 7 and 7q in 37% and 66% of cells, respectively. Taken together, we showed, for the first time, that pure erythroid leukemia presented as a myeloid sarcoma in the form of ovarian masses.

A practical approach to the flow cytometric detection and diagnosis of T-cell lymphoproliferative disorders

The flow cytometric analysis of T-cell malignancies is difficult due to the heterogeneity of T-cells and the lack of convenient methods to detect T-cell clonality. Neoplastic T-cells are most often detected by their altered level of surface antigen expression, and detection requires an extensive knowledge of the phenotype of normal T-lymphocytes. This review focuses on the methods to distinguish malignant T-cells from their normal counterparts and the phenotypic features of the T-cell lymphoproliferative disorders.

Anaplastic large cell lymphoma in leukemic phase: extraordinarily high white blood cell count

Anaplastic large cell lymphoma (ALCL) is a distinct type of T/null-cell non-Hodgkin lymphoma that commonly involves nodal and extranodal sites. The World Health Organization of lymphoid neoplasms recognizes two types: anaplastic lymphoma kinase (ALK) positive or ALK negative, the former as a result of abnormalities involving the ALK gene at chromosome 2p23. Patients with ALCL rarely develop a leukemic phase of disease, either at the time of initial presentation or during the clinical course. Described herein is a patient with ALK+ ALCL, small cell variant, associated with the t(2;5)(p23;q35), who initially presented with leukemic involvement and an extraordinarily high leukocyte count of 529 x 10(9)/L, which subsequently peaked at 587 x 10(9)/L. Despite chemotherapy the patient died 2(1/2) months after diagnosis. In the literature review 20 well-documented cases are identified of ALCL in leukemic phase reported previously, with a WBC ranging from 15 to 151 x 10(9)/L. Leukemic phase of ALCL occurs almost exclusively in patients with ALK+ ALCL, most often associated with the small cell variant and the t(2;5)(p23;q35), similar to the present case. Patients with leukemic phase ALK+ ALCL appear to have a poorer prognosis than most patients with ALK+ ALCL.

Flow Cytometric Immunophenotyping of Anaplastic Large Cell Lymphoma

Context.—Anaplastic large cell lymphoma (ALCL) is usually diagnosed by histologic and immunohistochemical analysis. However, fine-needle aspiration is becoming a popular alternative to lymph node biopsy, and flow-cytometric immunophenotyping is often used to analyze fine-needle aspiration specimens.

Objective.—To review our experience using flow-cytometric immunophenotyping to assess cases of ALCL and to evaluate the diagnostic utility of this technique.

Design.—Each case of ALCL was assessed by flow cytometry with 3-color or 4-color antibody panels, and data were reanalyzed by cluster analysis using Paint-a-Gate for cases with retrievable flow cytometry data files. Anaplastic lymphoma kinase (ALK) was assessed by using immunohistochemistry.

Results.—Twenty-three ALCL cases were analyzed by flow cytometry. In 4 cases, neoplastic cells could not be identified. In the remaining 19 cases (11 ALK+, 8 ALK−), all were positive for CD30 and CD45. Anaplastic large cell lymphoma cells were large and usually CD45 bright, with many or most cells falling in the region of monocytes on the CD45/side scatter plot. The frequencies of T-cell antigen expression in ALK+ cases were CD2, 67%; CD7, 60%; CD3, 45%; CD4, 33%; CD5, 14%; and CD8, 14%. In ALK− cases, the frequencies of the T-cell antigen expression were CD2, 100%; CD3, 50%; CD4, 40%; CD7, 40%; CD5, 25%; and CD8, 20%.

Conclusions.—Flow cytometry can be used to immunophenotype ALCL cases. Neoplastic cells may be few, and they may fall outside of the lymphocyte gate. Cluster analysis using software like Paint-A-Gate is often helpful because it allows for flexible, sequential gating strategies to identify and characterize the neoplastic cells.