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Lu C, Li M, Fu J, Fan X, Zhong L, Li Y, Xi Q. cyTRBC1 evaluation rapidly identifies sCD3-negative peripheral T-cell lymphomas and reveals a novel type of sCD3-negative T-cell clone with uncertain significance. CYTOMETRY. PART B, CLINICAL CYTOMETRY 2024. [PMID: 38818861 DOI: 10.1002/cyto.b.22182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/19/2024] [Accepted: 05/13/2024] [Indexed: 06/01/2024]
Abstract
The flow cytometry-based evaluation of TRBC1 expression has been demonstrated as a rapid and specific method for detecting T-cell clones in sCD3-positive TCRαβ+ mature T-cell lymphoma. The aim of the study was to validate the utility of surface (s) TRBC1 and cytoplastic (cy) TRBC1 assessment in detecting clonality of sCD3-negative peripheral T-cell lymphomas (PTCLs), as well as exploring the existence and characteristics of sCD3-negative clonal T-cell populations with uncertain significance (T-CUS). Evaluation of sTRBC1 and cyTRBC1 were assessed on 61 samples from 37 patients with sCD3-negative PTCLs, including 26 angioimmunoblastic T-cell lymphoma (AITL) patients and 11 non-AITL patients. The sCD3-negative T-CUS were screened from 1602 patients without T-cell malignancy and 100 healthy individuals. Additionally, the clonality of cells was further detected through T-cell gene rearrangement analysis. We demonstrated the monotypic expression patterns of cyTRBC1 in all sCD3-negative PTCLs. Utilizing the cyTRBC1 evaluation assay, we identified a novel and rare subtype of sCD3-negative T-CUS for the first time among 13 out of 1602 (0.8%) patients without T-cell malignancy. The clonality of these cells was further confirmed through T-cell gene rearrangement analysis. This subset exhibited characteristics such as sCD3-cyCD3 + CD4 + CD45RO+, closely resembling AITL rather than non-AITL. Further analysis revealed that sCD3-negative T-CUS exhibited a smaller clone size in the lymph node and mass specimens compared to AITL patients. However, the clone size of sCD3-negative T-CUS was significantly lower than that of non-AITL patients in both specimen groups. In conclusion, we validated the diagnostic utility of cyTRBC1 in detecting sCD3-negative T-cell clonality, provided a comprehensive analysis of sCD3-negative T-CUS, and established a framework and provided valuable insights for distinguishing sCD3-negative T-CUS from sCD3-negative PTCLs based on their phenotypic properties and clone size.
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Affiliation(s)
- Cong Lu
- Department of Cardiology, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Mingyong Li
- Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Jun Fu
- Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaoming Fan
- Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Ling Zhong
- Sichuan Provincial Key Laboratory for Human Disease Gene Study and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Yanxin Li
- Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
| | - Qian Xi
- Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China
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Devitt KA, Kern W, Li W, Wang X, Wong AJ, Furtado FM, Oak JS, Illingworth A. TRBC1 in flow cytometry: Assay development, validation, and reporting considerations. CYTOMETRY. PART B, CLINICAL CYTOMETRY 2024; 106:192-202. [PMID: 38700195 DOI: 10.1002/cyto.b.22175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/01/2024] [Accepted: 04/11/2024] [Indexed: 05/05/2024]
Abstract
The assessment of T-cell clonality by flow cytometry has long been suboptimal, relying on aberrant marker expression and/or intensity. The introduction of TRBC1 shows much promise for improving the diagnosis of T-cell neoplasms in the clinical flow laboratory. Most laboratories considering this marker already have existing panels designed for T-cell workups and will be determining how best to incorporate TRBC1. We present this comprehensive summary of TRBC1 and supplemental case examples to familiarize the flow cytometry community with its potential for routine application, provide examples of how to incorporate it into T-cell panels, and signal caution in interpreting the results in certain diagnostic scenarios where appropriate.
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Affiliation(s)
- Katherine A Devitt
- Department of Pathology and Laboratory Medicine, University of Vermont Medical Center, Burlington, Vermont, USA
- Larner College of Medicine at the University of Vermont, Burlington, Vermont, USA
| | - Wolfgang Kern
- Department of Flow Cytometry, MLL Munich Leukemia Laboratory, Munich, Germany
| | - Weijie Li
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Xuehai Wang
- Division of Hematopathology, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Allyson J Wong
- Pathology and Laboratory Medicine, Lahey Hospital and Medical Center, Burlington, Massachusetts, USA
| | - Felipe M Furtado
- Hematology Department, Sabin Diagnostico e Saude, Brasília, Brazil
- Oncohematology Department, Hospital da Criança de Brasília, Brasília, Brazil
| | - Jean S Oak
- Department of Pathology, Stanford University, Stanford, California, USA
| | - Andrea Illingworth
- Department of Flow Cytometry, Dahl-Chase Diagnostic Services/Versant Diagnostics, Bangor, Maine, USA
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Horna P, Weybright MJ, Ferrari M, Jungherz D, Peng Y, Akbar Z, Tudor Ilca F, Otteson GE, Seheult JN, Ortmann J, Shi M, Maciocia PM, Herling M, Pule MA, Olteanu H. Dual T-cell constant β chain (TRBC)1 and TRBC2 staining for the identification of T-cell neoplasms by flow cytometry. Blood Cancer J 2024; 14:34. [PMID: 38424120 PMCID: PMC10904869 DOI: 10.1038/s41408-024-01002-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 02/07/2024] [Accepted: 02/09/2024] [Indexed: 03/02/2024] Open
Abstract
The diagnosis of leukemic T-cell malignancies is often challenging, due to overlapping features with reactive T-cells and limitations of currently available T-cell clonality assays. Recently developed therapeutic antibodies specific for the mutually exclusive T-cell receptor constant β chain (TRBC)1 and TRBC2 isoforms provide a unique opportunity to assess for TRBC-restriction as a surrogate of clonality in the flow cytometric analysis of T-cell neoplasms. To demonstrate the diagnostic utility of this approach, we studied 164 clinical specimens with (60) or without (104) T-cell neoplasia, in addition to 39 blood samples from healthy donors. Dual TRBC1 and TRBC2 expression was studied within a comprehensive T-cell panel, in a fashion similar to the routine evaluation of kappa and lambda immunoglobulin light chains for the detection of clonal B-cells. Polytypic TRBC expression was demonstrated on total, CD4+ and CD8+ T-cells from all healthy donors; and by intracellular staining on benign T-cell precursors. All neoplastic T-cells were TRBC-restricted, except for 8 cases (13%) lacking TRBC expression. T-cell clones of uncertain significance were identified in 17 samples without T-cell malignancy (13%) and accounted for smaller subsets than neoplastic clones (median: 4.7 vs. 69% of lymphocytes, p < 0.0001). Single staining for TRBC1 produced spurious TRBC1-dim subsets in 24 clinical specimens (15%), all of which resolved with dual TRBC1/2 staining. Assessment of TRBC restriction by flow cytometry provides a rapid diagnostic method to detect clonal T-cells, and to accurately determine the targetable TRBC isoform expressed by T-cell malignancies.
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Affiliation(s)
- Pedro Horna
- Division of Hematopathology, Mayo Clinic, Rochester, MN, USA.
| | | | | | - Dennis Jungherz
- Department of Internal Medicine, University of Cologne, Cologne, Germany
| | - YaYi Peng
- Department of Internal Medicine, University of Cologne, Cologne, Germany
| | | | | | | | | | - Janosch Ortmann
- Centre de Recherches Mathematiques, Universite du Quebec a Montreal, Montreal, Canada
| | - Min Shi
- Division of Hematopathology, Mayo Clinic, Rochester, MN, USA
| | | | - Marco Herling
- Department of Internal Medicine, University of Cologne, Cologne, Germany
| | - Martin A Pule
- Autolus Ltd, London, UK
- Cancer Institute, University College London, London, UK
| | - Horatiu Olteanu
- Division of Hematopathology, Mayo Clinic, Rochester, MN, USA
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Castillo F, Morales C, Spralja B, Díaz-Schmidt J, Iruretagoyena M, Ernst D. Integration of T-cell clonality screening using TRBC-1 in lymphoma suspect samples by flow cytometry. CYTOMETRY. PART B, CLINICAL CYTOMETRY 2024; 106:64-73. [PMID: 38010106 DOI: 10.1002/cyto.b.22147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/23/2023] [Accepted: 10/12/2023] [Indexed: 11/29/2023]
Abstract
BACKGROUND The diagnosis of T-cell non-Hodgkin lymphomas (NHL) is challenging. The development of a monoclonal antibody specific for T-cell receptor β constant region 1 (TRBC1) provides an alternative to discriminate clonal T cells. The aim of this study was to evaluate the diagnostic potential of an anti-TRBC1 mAb for the identification of T-NHL. METHODS We performed a cross-sectional diagnostic analytic study of samples tested for lymphoma. All samples sent for lymphoma screening were first evaluated using the standard Euroflow LST, to which a second additional custom-designed T-cell clonality assessment tube was added CD45/TRBC1/CD2/CD7/CD4/TCRγδ/CD3. Flow cytometry reports were compared with morphological and molecular tests. RESULTS Fifty-nine patient samples were evaluated. Within the T-cell population, cut-off percentages in the CD4+ cells were from 29.4 to 54.6% and from 23.9 to 52.1% in CD8+ cells. Cut-off ratios in CD4+ T cells were from 0.33 to 1.1, and in CD8+ cells between 0.22 and 1.0. Using predefined normal cut-off values, 18 of 59 (30.5%) samples showed a restricted expression of TRBC1. A final diagnosis of a T-NHL was confirmed clinically and/or by histopathological studies in 15 of the 18 cases (83.3%). There were no cases of T-NHL by morphology/IHC with normal TRBC1 expression. Non-neoplastic patient samples behaved between predefined TRBC1 cut-off values. CONCLUSIONS Expression of TRBC1 provides a robust method for T-cell clonality assessment, with very high sensitivity and good correlation with complementary methods. TRBC1 can be integrated into routine lymphoma screening strategies via flow cytometry.
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Affiliation(s)
- Felipe Castillo
- Laboratorio Clínico, Clínica Alemana de Santiago, Vitacura, Chile
| | | | - Biserka Spralja
- Laboratorio Anatomía Patológica, Clínica Alemana de Santiago, Vitacura, Chile
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Joaquín Díaz-Schmidt
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- Departamento de Oncología, Clínica Alemana de Santiago, Vitacura, Chile
| | - Mirentxu Iruretagoyena
- Laboratorio Clínico, Clínica Alemana de Santiago, Vitacura, Chile
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Daniel Ernst
- Laboratorio Clínico, Clínica Alemana de Santiago, Vitacura, Chile
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- Departamento de Oncología, Clínica Alemana de Santiago, Vitacura, Chile
- Instituto de Ciencia e Innovación en Medicina (ICIM), Universidad del Desarrollo, Santiago, Chile
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Liu J, Li M, Fu J, Dong M, Fan X, Zhong L, Xu G, Li Y, Xi Q. sTRBC1 and cyTRBC1 Expression Distinguishes Indolent T-Lymphoblastic Proliferations From T-Lymphoblastic Leukemia/Lymphoma. Am J Surg Pathol 2023; 47:1325-1331. [PMID: 37515427 DOI: 10.1097/pas.0000000000002103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2023]
Abstract
Indolent T-lymphoblastic proliferation (iT-LBP) consists of a proliferation of non-neoplastic TdT + T cells in extrathymic tissues, requiring no treatment. However, due to overlapping clinical and histologic features, distinguishing iT-LBP from T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma (T-ALL/LBL) can be challenging. Recently, flow cytometry-based evaluation of TRBC1 has been used to detect of T-cell clonality in TCRαβ + mature T-cell lymphomas and aid in the differential diagnosis between T-ALL and normal thymocytes. We present a case of iT-LBP with high-grade serous ovarian carcinoma (HGSOC). To investigate the potential utility of TRBC1 expression in distinguishing iT-LBP from T-ALL/LBL, we assessed both surface (s) and cytoplasmic (cy) TRBC1 expression patterns on blast cells from the patient with iT-LBP and HGSOC as well as 11 patients diagnosed with T-ALL/LBL. The results revealed that sTRBC1 and cyTRBC1 exhibited polytypic expression patterns in patient with iT-LBP and HGSOC, while cyTRBC1 showed monotypic expression in those with T-ALL/LBL. This suggests that evaluation of sTRBC1 and cyTRBC1 expression can serve as a simple, rapid, and effective approach to differentiate between iT-LBP and T-ALL/LBL.
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Affiliation(s)
| | | | | | | | | | - Ling Zhong
- Sichuan Provincial Key Laboratory for Human Disease Gene Study and Department of Laboratory Medicine, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan Province, China
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Hristov AC, Tejasvi T, Wilcox RA. Cutaneous T-cell lymphomas: 2023 update on diagnosis, risk-stratification, and management. Am J Hematol 2023; 98:193-209. [PMID: 36226409 PMCID: PMC9772153 DOI: 10.1002/ajh.26760] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/05/2022] [Indexed: 02/04/2023]
Abstract
DISEASE OVERVIEW Cutaneous T-cell lymphomas are a heterogenous group of T-cell neoplasms involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS). DIAGNOSIS The diagnosis of MF or SS requires the integration of clinical and histopathologic data. RISK-ADAPTED THERAPY TNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral or the blood involvement are generally approached with systemic therapies, including biologic-response modifiers, histone deacetylase inhibitors, or antibody-based strategies, in an escalating fashion. In highly-selected patients, allogeneic stem-cell transplantation may be considered, as this may be curative in some patients.
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Affiliation(s)
- Alexandra C. Hristov
- Departments of Pathology and Dermatology, 2800 Plymouth Road, Building 35, Ann Arbor, MI 48109-2800
| | - Trilokraj Tejasvi
- Department of Dermatology, 1910 Taubman Center, 1500 E Medical Center Dr, Ann Arbor, MI 48109
| | - Ryan A. Wilcox
- Correspondence to: Ryan Wilcox, MD, PhD, Division of Hematology/Oncology, Department of Internal Medicine, University of Michigan Rogel Cancer Center, 1500 E. Medical Center Drive, Room 4310 CC, Ann Arbor, MI 48109-5948, Phone: (734) 615-9799, Fax: (734) 936-7376,
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Xi Q, Li M, Fu J, Fan X, Li Y. Cytoplasmic TRBC1 Expression in T-ALL and AITL. Am J Clin Pathol 2022; 158:775. [PMID: 36197794 DOI: 10.1093/ajcp/aqac111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Qian Xi
- University of Electronic Science and Technology of China, Chengdu, China
| | - Mingyong Li
- University of Electronic Science and Technology of China, Chengdu, China
| | - Jun Fu
- University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaoming Fan
- University of Electronic Science and Technology of China, Chengdu, China
| | - Yanxin Li
- University of Electronic Science and Technology of China, Chengdu, China
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Wang C, Zhu L, Liu S, Yi S, Xiao M, Zhang Y, Mao X. PD-1 combined with TRBC1 and pan-T cell antibodies for robustly monitoring angioimmunoblastic T-cell lymphoma. Front Med (Lausanne) 2022; 9:962428. [PMID: 36160159 PMCID: PMC9492947 DOI: 10.3389/fmed.2022.962428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundThe diagnosis of AITL is challenging. It may be delayed or even missed due to critical clinical conditions and its histologic and immunophenotypic overlap with other neoplastic and reactive lymphoid proliferations.ObjectiveThe key objective is to obtain an efficient diagnosis, sensitive disease monitoring and treatment efficacy assessment of AITL using multiparameter flow cytometry (MFC).MethodsIn total, 167 de novo AITL patients were immunophenotypically profiled using sensitive MFC. We precisely identified the aberrant T-cell populations of AITL and performed an in-depth description of their phenotypic characteristics in comparison with their residual normal CD4+ T cells. A comparison of Programmed death receptor-1 (PD-1) expression was performed among AITL and other T-cell lymphomas.ResultsMFC detected a neoplastic T-cell population in 94.1% (80/85) of tissue, 71.5% (108/151) of bone marrow (BM), 100% (8/8) of peripheral blood (PB) and 78.6% (11/14) of body fluid samples. The most frequent immunophenotypic aberrations included the absence and diminished expression of CD3 (71.25% in tissues, 71.3% in BM, 75% in PB, 81.8% in hydrothorax and ascites specimens), followed by the loss or partial loss of CD7 (71.25% in LN, 67.6% in BM, 50% in PB, 81.8% in hydrothorax and ascites specimens). The immunophenotyping of neoplastic T-cell populations showed a high degree of similarity among different sites of the same patient and they might change over time but were relatively stable. Bright PD-1 expression showed high sensitivity and specificity in differentiating AITL from other T-cell lymphomas. In 14 AITL patients, neoplastic T-cell populations were initially missed by T-cell screening tube but were successfully discovered by bright PD-1 expression.ConclusionT-cell screening tube can reliably screen neoplastic T-cell populations in AITL patients with typical immunophenotyping, such as loss of surface CD3 and loss of CD7 with a relatively high ratio. Bright PD-1 expression is essential for identifying aberrant T cells in almost all AITLs. The clonality assessment antibody TRBC1 is efficient for robustly and cheaply assessing T-cell clonality. Using PD-1 and TRBC1 combined with pan-T cell antibodies can make a precise diagnosis of AITL and also sensitively monitor minimal residual disease regardless of the antigenic drift of the neoplastic T cells.
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Wheeler A, Laziuk K, Hammer RD. Flow Cytometric Evaluation of Cytoplasmic TRBC1 Expression. Am J Clin Pathol 2022; 157:956-957. [PMID: 35136905 DOI: 10.1093/ajcp/aqac006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Saglam A, Singh K, Gollapudi S, Kumar J, Brar N, Butzmann A, Warnke R, Ohgami RS. Indolent T-lymphoblastic proliferation: A systematic review of the literature analyzing the epidemiologic, clinical, and pathologic features of 45 cases. Int J Lab Hematol 2022; 44:700-711. [PMID: 35577551 DOI: 10.1111/ijlh.13873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 04/25/2022] [Indexed: 11/26/2022]
Abstract
An indolent T-lymphoblastic proliferation (iT-LBP) is a rare benign disorder characterized by an abnormal expansion of immature T-cells, which morphologically can mimic malignancy. Since the first case was described in 1999, dozens more have been reported in the literature. However, the epidemiologic, clinical, pathologic, and biologic features of this disease have not been well described. Here, we retrospectively reviewed all known cases reported in the literature to better understand this entity. A PubMed search up to January 2022 highlighted 25 papers describing cases/case series of iT-LBP, one of which was a case presentation in a slide workshop. Except for 9 of the cases in one of the papers, where it was evident that the number of CD3+/TdT+ cells were too few to conform with a diagnosis of iT-LBP, all papers and all the cases reported were included in the study amounting to a total of 45 cases. Clinicopathologic characteristics were analyzed using descriptive statistics and frequencies. Our analysis highlighted the previously known association with Castleman disease and Castleman-like features and underlined its association with dendritic cell proliferations in general, as well as uncovering high frequency of concurrence with hepatocellular carcinoma and autoimmune diseases, most notably myasthenia gravis, paraneoplastic pemphigus and paraneoplastic autoimmune multiorgan syndrome. Furthermore, the co-expression of CD4 and CD8 and high prevalence of extranodal disease and recurrences were other less well described features that were revealed.
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Affiliation(s)
- Arzu Saglam
- Department of Pathology, Hacettepe University, Ankara, Turkey
| | - Kunwar Singh
- Department of Pathology, University of California San Francisco, San Francisco, California, USA
| | - Sumanth Gollapudi
- Department of Pathology, University of California San Francisco, San Francisco, California, USA
| | - Jyoti Kumar
- Department of Pathology, Stanford University, Stanford, California, USA
| | - Nivaz Brar
- Department of Pathology, Stanford University, Stanford, California, USA
| | - Alexandra Butzmann
- Department of Pathology, University of California San Francisco, San Francisco, California, USA
| | - Roger Warnke
- Department of Pathology, Stanford University, Stanford, California, USA
| | - Robert S Ohgami
- Department of Pathology, University of California San Francisco, San Francisco, California, USA
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