T-cell large granular lymphocyte leukemia associated with myelodysplastic syndrome: a clinicopathologic study of nine cases

Large Granular Lymphocytic Leukemia: Clinical Features, Molecular Pathogenesis, Diagnosis and Treatment

Large granular lymphocytic (LGL) leukemia is a lymphoproliferative disorder characterized by persistent clonal expansion of mature T- or natural killer cells in the blood via chronic antigenic stimulation. LGL leukemia is associated with specific immunophenotypic and molecular features, particularly STAT3 and STAT5 mutations and activation of the JAK-STAT3, Fas/Fas-L and NF-κB signaling pathways. Disease-related deaths are mainly due to recurrent infections linked to severe neutropenia. The current treatment is based on immunosuppressive therapies, which frequently produce unsatisfactory long-term responses, and for this reason, personalized approaches and targeted therapies are needed. Here, we discuss molecular pathogenesis, clinical presentation, associated autoimmune disorders, and the available treatment options, including emerging therapies.

Genomic landscape of T-large granular lymphocyte leukemia and chronic lymphoproliferative disorder of NK cells: a single institution experience

LGLL is a rare and chronic lymphoproliferative disorder including T-LGLL and CLPD-NK. Here, we investigated the genomic profiles of LGLL with a focus on STAT3 and STAT5B mutations in a cohort of 49 patients (41 T-LGLL, 8 CLPD-NK). Our study indicated that STAT3 was identified in 38.8% (19/49) of all patients, while STAT5B occurred in only 8.2% (4/49) of patients. We found that STAT3 mutations were associated with lower ANC in T-LGLL patients. The average number of pathogenic/likely pathogenic mutations in STAT3/STAT5B-mutated patients was significantly higher than that in WT patients (1.78 ± 1.17 vs 0.65 ± 1.36, p = 0.0032). Additionally, TET2-only mutated T-LGLL (n = 5) had a significant reduction in platelet values compared with the WT (n = 16) or STAT3-only mutated T-LGLL (n = 12) (p < 0.05). In conclusion, we compared the somatic mutational landscape between STAT3/STAT5B WT and mutated patients and correlate with their distinct clinical characteristics.

Immune dysregulation and potential targeted therapy in myelodysplastic syndrome

Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal hematological diseases and a high risk for transformation to acute myeloid leukemia (AML). The identification of key genetic alterations in MDS has enhanced our understanding of the pathogenesis and evolution. In recent years, it has been found that both innate and adaptive immune signaling are activated in the hematopoietic niche of MDS with aberrant cytokine secretion in the bone marrow microenvironment. It is also clear that immune dysregulation plays an important role in the occurrence and progression of MDS, especially the destruction of the bone marrow microenvironment, including hematopoiesis and stromal components. The purpose of this review is to explore the role of immune cells, the immune microenvironment, and cytokines in the pathogenesis of MDS. Insights into the mechanisms of these variants may facilitate the development of novel effective treatments to prevent disease progression.

Autoimmune disorders associated with myelodysplastic syndromes: clinical, prognostic and therapeutic implications

Around one third of patients with myelodysplastic syndromes (MDS) suffer from concomitant autoimmune disorders (AD). However the actual burden of such an association appears to be quite heterogeneous in different studies probably due to variable criteria in selecting both MDS patients and subtypes of AD. Moreover, both the prognostic implications and the potential applications of specific therapeutic approaches in this patient subgroup are still at least partially under debate. The present review will try to shed some further light on the clinical association between MDS and AD in order to better delineate its prognostic significance and to suggest potential therapeutic algorithms available for these patients.

Large Granular Lymphocyte Expansion in Myeloid Diseases and Bone Marrow Failure Syndromes: Whoever Seeks Finds

Large granular lymphocytes (LGL) are lymphoid cells characterized by either a T-cell or a natural killer phenotype whose expansion may be reactive to toxic, infectious, and neoplastic conditions, or result from clonal selection. Recently, the higher attention to LGL clones led to their detection in many clinical conditions including myeloid neoplasms and bone marrow failures. In these contexts, it is still unclear whether LGL cells actively contribute to anti-stem cell autoimmunity or are only a reaction to dysplastic/leukemic myelopoiesis. Moreover, some evidence exists about a common clonal origin of LGL and myeloid clones, including the detection of STAT3 mutations, typical of LGL, in myeloid precursors from myelodysplastic patients. In this article we reviewed available literature regarding the association of LGL clones with myeloid neoplasms (myelodysplastic syndromes, myeloproliferative neoplasms, and acute myeloid leukemias) and bone marrow failures (aplastic anemia and pure red cell aplasia, PRCA) focusing on evidence of pathogenic, clinical, and prognostic relevance. It emerged that LGL clones may be found in up to one third of patients, particularly those with PRCA, and are associated with a more cytopenic phenotype and good response to immunosuppression. Pathogenically, LGL clones seem to expand after myeloid therapies, whilst immunosuppression leading to LGL depletion may favor leukemic escape and thus requires caution.

[Clinical and laboratory characteristics in patients with myeloid neoplasms complicated with clonal T large granular lymphocyte proliferation]

Objective: To analyze the clinical manifestations and laboratory features in patients with myeloid neoplasms complicated with clonal T large granular lymphocyte (T-LGL) proliferation. Methods: The clinical data of 5 patients with myeloid neoplasms complicated with clonal T-LGL proliferation from November 2017 to November 2018 in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College were analyzed retrospectively. Results: The median age was 60 years old. All patients had a history of abnormal peripheral blood cell counts for over 6 months. The absolute lymphocyte count in peripheral blood was less than 1.0×10(9)/L. In addition to the typical T-LGL phenotype, the immunophenotype was heterogenous including CD4(+)CD8(-) in 2 patients, the other 3 CD4(-)CD8(+). Four patients were αβ type T cells, the other one was γδ type. STAT3 mutation was detected in 1 patient by next-generation sequencing, the other 4 cases were negative. Conclusions: Clonal T-LGL proliferation with myeloid neoplasm develops in an indolent manner, mainly in elderly patients. Hemocytopenia is the most common manifestation. The diagnosis of T-LGL proliferation does not have specific criteria, that it should be differentiated from other T cell proliferative disorders, such as T-cell clones of undetermined significance. STAT3 or STAT5b mutation may help distinguish.

Pruritic arthropod bite-like papules in T-cell large granular lymphocytic leukaemia and chronic myelomonocytic leukaemia

T-cell large granular lymphocytic leukaemia (T-LGLL) is a clinically indolent mature T-cell neoplasm characterized by a monoclonal population of CD3+ CD8+ cytotoxic T cells, which usually presents as neutropenia, anaemia and thrombocytopenia. Chronic myelomonocytic leukaemia (CMML) is a clonal haematopoietic disorder with features of both a myeloproliferative neoplasm and myelodysplastic syndrome (MDS). Patients with CMML exhibit a persistent peripheral blood monocytosis in addition to myelodysplastic features. Because of the rarity of T-LGLL, its cutaneous manifestations are poorly documented, but include vasculitis, vasculopathy, persistent ulcerations, generalized pruritus and disseminated granuloma annulare. Various types of skin lesions have been observed in patients with CMML and reportedly occur in approximately 10% of cases. We report the extraordinary case of a patient with MDS who developed T-LGLL, and subsequently the MDS progressed to CMML. The patient then developed diffuse arthropod bite-like papules and intractable pruritus.

Clinical Features, Pathogenesis, and Treatment of Large Granular Lymphocyte Leukemias

Large granular lymphocytes (LGLs) are large lymphocytes with azurophilic granules in their cytoplasm. LGLs are either natural killer (NK) cells or T lymphocytes. Expansions of the LGLs in the peripheral blood are seen in various conditions, including three clonal disorders: T-cell LGL (T-LGL) leukemia, chronic lymphoproliferative disorders of NK cells (CLPD-NK), and aggressive NK-cell leukemia (ANKL). However, the monoclonal and polyclonal expansion of LGLs has been associated with many other conditions. The present article describes these LGL disorders, with special emphasis on the clinical features, pathogenesis, and treatments of the three above-mentioned clonal disorders.

T-cell large granular lymphocyte proliferation in myelodysplastic syndromes: Clinicopathological features and prognostic significance

Inflammatory and immune dysregulation are crucial in the initiation and development of myelodysplastic syndromes (MDS). It is noted that clonal T-cell large granular lymphocyte (T-LGL) proliferation associated with MDS is not uncommon. However, clinicopathological features, and prognostic and predictive value of presence of T-LGL proliferation in MDS patients is not very clear. This study compared 35 MDS patients with T-LGL proliferation with 36 MDS patients without T-LGL proliferation and summarized clinicopathologic features, including peripheral blood LGL cell counts, immunophenotype, T cell receptor gene rearrangement, bone marrow hematopoietic status, and adjuvant immunosuppressive therapy. The peripheral blood CD3+/CD57+ cell counts were significantly different (p<0.01) between the two groups. Notably, on examination of the bone marrow, MDS patients with T-LGL proliferation showed more frequent hypocellularity and/or lineage hypoplasia, particularly erythroid hypoplasia. On survival analysis, no overall difference was noted between MDS patients with T-LGL proliferation and those without T-LGL proliferation, and between the patients who received therapy for LGL and those who did not receive adjuvant therapy for LGL in the same risk group. In conclusion, T-LGL proliferation present in MDS patients can be associated with bone marrow hypocellularity and lineage hypoplasia. Although immunosuppressive therapy to eliminate T-LGL cells is potentially beneficial to the MDS patients with associated T-LGL proliferation, there is no overall survival benefit to the patients who received such treatment.

Clinicopathologic, Immunophenotypic, Cytogenetic, and Molecular Features of γδ T-Cell Large Granular Lymphocytic Leukemia: An Analysis of 14 Patients Suggests Biologic Differences With αβ T-Cell Large Granular Lymphocytic Leukemia. [corrected]

OBJECTIVES

T-cell large granular lymphocytic (T-LGL) leukemia is a rare disorder in which the neoplastic cells usually express the αβ T-cell receptor (TCR). To determine the significance of γδ TCR expression in this leukemia, we compared the clinicopathologic, immunophenotypic, and genetic features of patients with T-LGL leukemia expressing γδ TCR or αβ TCR.

METHODS

We used the World Health Organization classification criteria to confirm the diagnosis. All patients were diagnosed and treated at our institution.

RESULTS

We identified 14 patients with γδ T-LGL leukemia, 11 men and three women; six (43%) patients had a history of rheumatoid arthritis, 10 (71%) had neutropenia, four (29%) had thrombocytopenia, and three (21%) had anemia. Eight (67%) of 12 patients had a CD4-/CD8- phenotype, and four (33%) had a CD4-/CD8+ phenotype. The median overall survival was 62 months. Patients with γδ T-LGL leukemia were more likely to have rheumatoid arthritis (P = .04), lower absolute neutrophil count (P = .04), lower platelet count (P = .004), and a higher frequency of the CD4-/CD8- phenotype (P < .0001). However, there was no significant difference in overall survival between the two groups (P = .64).

CONCLUSIONS

Although patients with γδ and αβ T-LGL leukemia show some different clinical or phenotypic features, overall survival is similar, suggesting that γδ TCR expression does not carry prognostic significance.

Distinct effect of cyclophosphamide and cyclosporine on pure red cell aplasia associated with T-cell large granular lymphocyte leukemia

Large granular lymphocyte (LGL) leukemia is characterized by a clonal proliferation of large-sized lymphocytes with prominent large azurophilic cytoplasmic granules. Although most cases of T-LGL leukemia are indolent and asymptomatic during the course of the disease, some present with pure red cell aplasia (PRCA) and require therapy. We here reported a case of T-LGL leukemia complicated by PRCA in which anemia was resistant to cyclosporine and had been controlled for several years by cyclophosphamide; however, progressive anemia developed despite the administration of cyclophosphamide, but was ameliorated by the re-administration of cyclosporine. The present case demonstrated the 3 different phases of T-LGL proliferation associated with anemia (1st, T-LGL leukemia; 2nd, polyclonal T-LGL expansion; 3rd, myelodysplastic syndrome). We also showed that cyclophosphamide was effective when PRCA was caused by increased numbers of LGL, whereas cyclosporine was administered when hypoplastic myelodysplastic syndrome was suspected as the main cause of anemia. Repetitive bone marrow examinations should be performed throughout the course of T-LGL in order to monitor combined myelodysplastic syndrome.

Spectrum of Clonal Large Granular Lymphocytes (LGLs) of αβ T Cells: T-Cell Clones of Undetermined Significance, T-Cell LGL Leukemias, and T-Cell Immunoclones

OBJECTIVES

Clones of T-cell large granular lymphocytes (LGLTs) were detected by flow cytometry. Disease associations are described.

METHODS

Flow cytometry on blood or marrow detected clonal LGLTs by analyzing variable regions of the T-cell receptor β chain.

RESULTS

LGLT clones were detected in 20% (54/264) of tested patients. The clone sizes were less than 2.0 × 10(9)/L in the blood in 73% and less than 10% of marrow space in 94%. Blood counts showed cytopenias. Clinical associations included B-cell clones, myeloid neoplasms, nonneoplastic disorders of blood or marrow, transplants, systemic immune disorders, carcinomas, or hypothyroidism. Twelve patients had LGLT leukemia. Most (76%) had small LGLT clones with limited impact on the clinical management.

CONCLUSIONS

Most of the LGLT clones detected by flow cytometry were small and did not change the clinical management. We propose the following terminology: T-cell clones of undetermined significance, LGLT leukemias, and T-cell immunoclones.

Pathology of T-cell lymphomas: diagnosis and biomarker discovery

T-cell lymphomas are a group of predominantly rare hematologic malignancies that tend to recapitulate different stages of T-cell development, in a similar way that B-cell lymphomas do. As opposed to B-cell lymphomas, the understanding of the biology and the classification of T-cell lymphomas are somewhat rudimentary, and numerous entities are still included as 'provisional categories' in the World Health Classification of hematolopoietic malignancies. A relevant and useful classification of these disorders have been difficult to accomplish because of the rarity nature of them, the relative lack of understanding of the molecular pathogenesis, and their morphological and immunophenotypical complexity. Overall, T-cell lymphomas represent only 15 % of all non-Hodgkin lymphomas. This review is focused on addressing the current status of the categories of mature T-cell leukemias and lymphomas (nodal and extranodal) using an approach that incorporates histopathology, immunophenotype, and molecular understanding of the nature of these disorders, using the same philosophy of the most recent revised WHO classification of hematopoietic malignancies.

Advances in diagnosis and treatment of large granular lymphocyte syndrome

PURPOSE OF REVIEW

Large granular lymphocyte (LGL) syndrome comprises a clonal spectrum of T-cell and natural killer (NK)-cell LGL lymphoproliferative disorders associated with neutropenia. This review presents advances in diagnosis and therapy of LGL syndrome.

RECENT FINDINGS

Due to the lack of a single unique genetic or phenotypic feature and clinicopathological overlap between reactive and neoplastic entities, accurate LGL syndrome diagnosis should be based on the combination of morphologic, immunophenotypic, and molecular studies as well as clinical features. For diagnosis and monitoring of LGL proliferations, it is essential to perform flow cytometric blood and/or bone marrow analysis using a panel of monoclonal antibodies to conventional and novel T-cell and NK-cell antigens such as NK-cell receptors and T-cell receptor β-chain variable region families together with TCR gene rearrangement studies. Treatment of symptomatic cytopenias in patients with indolent LGL leukemia is still based on immunosuppressive therapy. Treatment with purine analogs and alemtuzumab may be considered as an alternative option.

SUMMARY

Progress in understanding the pathogenetic mechanisms of these entities, especially resistance of clonal LGLs to apoptosis, due to constitutive activation of survival signaling pathways, has its impact on identification of potential molecular therapeutic targets.

Allergic diseases and risk of hematopoietic malignancies in a cohort of postmenopausal women: a report from the Iowa Women's Health Study

BACKGROUND

Allergic diseases signify immune dysregulation attributable to underlying genetics and environmental exposures. Associations between various allergies and hematopoietic cancers have been observed, albeit inconsistently; however, few prospective studies have examined the risk, and even fewer among older adults.

METHODS

We examined risk of incident hematopoietic cancers in those reporting allergic diseases in a population-based cohort of 22,601 older women (Iowa Women's Health Study). Self-reported allergic status, including asthma, hay fever, eczema, and/or other allergies, was determined via questionnaire in 1997 (mean age, 72 years; range, 63-81 years). Incident cancers were ascertained by linkage with the Iowa Cancer Registry from 1997 to 2011. Cox proportional hazards regression was performed to estimate multivariate-adjusted HR and 95% confidence intervals (CI) for myeloid (N = 177) and lymphoid (N = 437) malignancies, respectively.

RESULTS

Allergic diseases were not associated with risk of myeloid (HR, 1.00; 95% CI, 0.72-1.37) or lymphoid (HR, 0.99; 95% CI, 0.81-1.22) malignancies overall, or for most allergic and malignant subtypes examined. Self-reported asthma was positively associated with development of myelodysplastic syndrome (MDS; HR, 2.00; 95% CI, 0.93-4.32). In addition, there was a 30% to 40% decrease in risk of both lymphoid and myeloid cancers in those reporting rural residences but no association in those reporting urban residences; the interaction between residence and allergy was statistically significant for lymphoid malignancies (Pinteraction = 0.05).

CONCLUSIONS AND IMPACT

These results suggest that asthma may contribute to the pathogenesis of MDS, a finding consistent with the chronic antigen stimulation hypothesis. Susceptibility differences by location of residence are concordant with the hygiene hypothesis and merit additional exploration.

Histopathological and immunohistochemical evaluation of bone marrow biopsy in myelodysplastic syndromes

SUMMARY In myelodysplastic syndromes (MDS), bone marrow biopsy (BMB) is now considered part of a multidisciplinary approach to bone marrow (BM) examination that must include cytological and cytogenetic assessment, while flow-cytometry and molecular studies can provide additional useful information. Undervalued in the past, BM histology has recently grown in importance in terms of diagnosis (i.e., MDS with BM fibrosis, hypoplastic MDS) and prognostic assessment (i.e., clusters of CD34+ blasts). Thus, BM histology must be considered complementary and not overlapping with the results of the other methods of BM study. Moreover, in recent years, numerous clinico-pathological studies have evidentiated, codified and standardized a series of histopathological parameters that are now considered essential for an effective and clinically useful histomorphological evaluation of the BMB. The aim of this work is to describe the histopathological and immunohistochemical approach to BMB that the pathologists of the Lombard Hematological Network (Rete Ematologica Lombarda [REL]; Italy) are carrying out on a standardized and shared basis in MDS patients.

Dysplasia has A differential diagnosis: distinguishing genuine myelodysplastic syndromes (MDS) from mimics, imitators, copycats and impostors

Just as a pawnshop owner who is unable to distinguish a genuine Rolex™ watch from a cheap knockoff courts financial ruin, the physician who fails to discriminate between authentic myelodysplastic syndromes (MDS) and conditions resembling MDS risks misinforming or harming patients. This review summarizes minimal criteria for diagnosing MDS and discusses common diagnostic challenges. MDS needs to be separated from numerous neoplastic and non-clonal hematologic disorders that can mimic MDS, including other myeloid neoplasms, nutritional deficiencies, toxin exposures, aplastic anemia, and inherited disorders (e.g., congenital sideroblastic anemia). Some distinctions are more critical therapeutically than others; e.g., recognizing B12 deficiency is more important than parsing high-risk MDS from erythroleukemia. Diagnostically ambiguous cases may be assigned holding-pattern terms, "idiopathic cytopenia(s) of undetermined significance" (ICUS) or "idiopathic dysplasia of undetermined significance" (IDUS), while awaiting clarifying information or further clinical developments. In the future, advances in molecular pathology will improve diagnostic accuracy, especially in morphologically non-descript cases.

Autoimmune manifestations in large granular lymphocyte leukemia

Large granular lymphocyte (LGL) leukemia features a group of indolent lymphoproliferative diseases that display a strong association with various autoimmune conditions. Notwithstanding, these autoimmune conditions have not been comprehensively characterized or systematized to date. As a result, their clinical implications remain largely unknown. The authors offer a comprehensive review of the existing literature on various autoimmune conditions documented in the course of T-cell LGL (T-LGL) leukemia. Though some of them are thought be secondary to the LGL leukemia, others could be primary and might even play a role in its pathogenesis. A considerable clinico-laboratory overlap between T-LGL leukemia associated with rheumatoid arthritis and Felty's syndrome suggests that they are just different eponyms for the same clinical entity.

Clonal drift demonstrates unexpected dynamics of the T-cell repertoire in T-large granular lymphocyte leukemia

T-cell large granular lymphocyte leukemia (T-LGLL) is characterized by chronic lymphoproliferation of cytotoxic T lymphocytes (CTLs) and is associated with lineage-restricted cytopenias. Introduction of T-cell receptor (TCR) variable β-chain (Vβ) monoclonal antibodies has facilitated identification and enumeration of clonal CTLs by flow cytometry. A highly skewed TCR Vβ repertoire identified by flow cytometry is strongly associated with monoclonal CDR3 regions by quantitative sequencing and positive TCRγ rearrangement assays. Therefore, Vβ expansions can serve as surrogate markers of CTL clonality to assess clonal kinetics in T-LGLL. We analyzed the TCR repertoire in 143 patients, 71 of which were available for serial measurements over 6 to 96 months. Although the majority (38/71, 54%) maintained a consistent monoclonal expansion, many (26/71, 37%) unexpectedly displayed a change in the dominant clone, whereby the original CTL clone contracted and another emerged as demonstrated by Vβ typing. Our results demonstrate that the T-cell repertoire is more dynamic in T-LGLL than recognized previously, illustrating the heterogeneity of disorders under this categorization.

A case report: Concurrent chronic myelomonocytic leukemia and T-cell large granular lymphocytic leukemia-type clonal proliferation as detected by multiparametric flow cytometry

BACKGROUND

Chronic myelomonocytic leukemia (CMML) is a subtype of myelodysplastic/myeloproliferative neoplasm. Although several studies have reported concurrent myelodysplastic syndrome (MDS) and T-cell large granular lymphocytic leukemia (T-LGL), coexistence of CMML and T-LGL has not been characterized. We describe here a unique case of CMML plus an underlying T-LGL-type clonal proliferation in a patient with a long standing history of severe anemia and recent pancytopenia.

METHODS

Multiparametric immunophenotyping by flow cytometry was conducted using fresh peripheral blood collected in EDTA. In addition, morphologic evaluation of the peripheral blood smear and T-cell gene rearrangement studies by polymerase chain reaction (PCR) were performed.

RESULTS

Flow cytometric analysis revealed abnormal monocytosis with multiple aberrancies including expression of cross-lineage markers CD2 and CD56, plus reduced expression of multiple antigens. In addition, abnormal CD8+ T-cells were identified, demonstrating dim expression of CD5 and dim to complete loss of CD7. In correlation with clinical history and morphologic review, a diagnosis of CMML plus underlying abnormal CD8+ T-cell lymphoproliferation was made. The clonality of these abnormal T-cells was confirmed by T-cell gene rearrangement studies.

CONCLUSIONS

We have identified a unique case of CMML in association with subclinical T-LGL, neither of which, alone, could fully explain the clinicopathologic features identified. Our findings suggest that the coexistence of these two entities may not be coincidental, and it is likely that they may share a common pathogenic pathway related to immune-dysregulation.