Catch the Calcium: T-Cell Histiocyte-Rich B-Cell Lymphoma Presenting as Hypercalcemia

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is an extremely rare and aggressive subtype of diffuse large B-cell lymphoma (DLBCL) that typically presents in middle-aged patients and carries a poor prognosis. Hypercalcemia presenting as the initial manifestation of the disease is rare, with only one other case reported in the literature. We report a case of a 90-year-old male who presented with progressive lethargy and unintentional weight loss. Initial workup showed elevated serum calcium of 14.6 mg/dL, corrected for albumin, and creatinine of 1.51 mg/dL. He had a suppressed iPTH of 6.3 pg/mL and normal PTHrP (13 pg/mL). Computed tomography (CT) scan of the abdomen and pelvis was performed to rule out underlying malignancy, which showed splenomegaly and enlarged retrocrural and porta hepatis lymph nodes. Bone marrow biopsy was performed to evaluate for hematological malignancy, which revealed findings diagnostic of THRLBCL. While rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is one of the mainstay therapies for DLBCL and has been shown to have comparable outcomes in THRLBCL, there are documented concerns with its toxicity profile limiting the ability of older patients (60 years and older) to complete therapy. Our patient was treated with R-mini-CHOP, which is much better tolerated in this patient demographic. R-mini-CHOP features decreased doses of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with the conventional dose of rituximab. This case discusses a rare subtype of non-Hodgkin lymphoma presenting with a unique manifestation of hypercalcemia. We highlight the importance of thorough investigation for causes of hypercalcemia as well as the efficacy and tolerability of R-mini-CHOP in this elderly patient demographic.

Microenvironmental immune cell alterations across the spectrum of nodular lymphocyte predominant Hodgkin lymphoma and T-cell/histiocyte-rich large B-cell lymphoma

Background

The clinicopathological spectrum of nodular lymphocyte predominant Hodgkin lymphoma (NLPHL), also known as nodular lymphocyte predominant B-cell lymphoma, partially overlaps with T-cell/histiocyte-rich large B-cell lymphoma (THRLCBL). NLPHL histology may vary in architecture and B-cell/T-cell composition of the tumour microenvironment. However, the immune cell phenotypes accompanying different histological patterns remain poorly characterised.

Methods

We applied a multiplexed immunofluorescence workflow to identify differential expansion/depletion of multiple microenvironmental immune cell phenotypes between cases of NLPHL showing different histological patterns (as described by Fan et al, 2003) and cases of THRLBCL.

Results

FOXP3-expressing T-regulatory cells were conspicuously depleted across all NLPHL cases. As histology progressed to variant Fan patterns C and E of NLPHL and to THRLBCL, there were progressive expansions of cytotoxic granzyme-B-expressing natural killer and CD8-positive T-cells, PD1-expressing CD8-positive T-cells, and CD163-positive macrophages including a PDL1-expressing subset. These occurred in parallel to depletion of NKG2A-expressing natural killer and CD8-positive T-cells.

Discussion

These findings provide new insights on the immunoregulatory mechanisms involved in NLPHL and THLRBCL pathogenesis, and are supportive of an increasingly proposed biological continuum between these two lymphomas. Additionally, the findings may help establish new biomarkers of high-risk disease, which could support a novel therapeutic program of immune checkpoint interruption targeting the PD1:PDL1 and/or NKG2A:HLA-E axes in the management of high-risk NLPHL and THRLBCL.

The spectrum of nodular lymphocyte predominant Hodgkin lymphoma: a report of the lymphoma workshop of the 20th meeting of the European Association for Haematopathology

Session 4 of the 2021 European Association of Haematopathology/Society for Hematopathology Workshop focused on nodular lymphocyte predominant Hodgkin lymphoma (NLPHL). First, the spectrum of immunophenotypic variations in NLPHL and the defining criteria for classic Hodgkin Lymphoma (CHL) were discussed. The added value of further immunophenotypic characterization of both tumor cells and microenvironment to support the differential diagnosis was presented. Next, unusual cases with combined growth patterns and evolution of morphological features over time were presented to explore the clinicopathological impact of presumed high-risk patterns. Based on a large collection of cases, the defining morphological, immunophenotypical, and gene expression features of T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) and THRLBCL-like NLPHL (pattern E) were reviewed to explore this challenging differential diagnosis and critically evaluate whether aggressive behavior and transformation of NLPHL can be predicted in practice.

Refractory T-cell/histiocyte-rich large B-cell lymphoma in a patient with ataxia-telangiectasia caused by novel compound heterozygous variants in ATM

Ataxia-telangiectasia (A-T) is an autosomal recessive chromosomal breakage syndrome caused by mutation of the ATM (A-T mutated) gene, which encodes a protein kinase that has a major role in the cellular response to DNA damage. Approximately, 10% of A-T patients develop lymphoid malignancies. Deaths caused by extreme sensitivity to chemotherapy for malignancy have been reported, and cancer treatment in A-T is extraordinarily difficult, needing careful monitoring and individualized protocols. We report the case of a 12-year-old girl with A-T diagnosed at the age of 3 in association with IgA deficiency and recurrent pulmonary infections. Sanger sequencing revealed compound heterozygosity of the ATM gene, which bore two novel mutations. At the age of 12, she developed stage IV T-cell/histiocyte-rich large B-cell lymphoma. The tumor was resistant to chemotherapy, and she unfortunately died of cardiac insufficiency and multiple organ failure induced by rapid progression of the disease. The treatment approach for children with A-T and advanced-stage B-non-Hodgkin lymphoma must be refined.

Metabolic tumor volume, cancer cell fraction, and prognosis - the case of T-cell/histiocyte-rich large B-cell lymphoma

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is a rare aggressive lymphoma characterized by a paucity of neoplastic B-cells and a majority of reactive T-cells with or without histiocytes. In the 'Positron Emission Tomography-Guided Therapy of Aggressive Non-Hodgkin Lymphomas' trial (clinicaltrials.gov NCT00554164; EudraCT 2006-001641-33), its frequency was less than 3%. While cancer cell content by quantitative histology was 10-times lower, baseline total metabolic tumor volume (TMTV) by 18-fluorodesoxyglucose positron emission tomography was 10-times higher in THRLBCL than in diffuse large B-cell lymphoma (DLBCL). When THRLBCL and DLBCL populations were matched for TMTV, the survival curves were superimposable. However, when the populations were matched for cancer cell volume by multiplying TMTV by cancer cell fraction, outcome in THRLBCL was worse than in DLBCL. Whether genetic differences between cancer cells, tumor-promoting properties of non-neoplastic cells, or both are responsible for inferior cancer cell volume-related outcome in THRLBCL, remains to be elucidated.

Hypercalcemia in T-Cell/Histiocyte-Rich Large B-Cell Lymphoma: An Unusual Presentation of a Rare Disease and Literature Review

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is an extremely rare morphologic subtype of diffuse large B-cell lymphoma (DLBCL), accounting for only 1-3% of total cases. It is considered an aggressive lymphoma with a poor prognosis. Hypercalcemia has been described as an uncommon presenting symptom of patients with DLBCL in several case reports. Here, we report an unusual case of severe hypercalcemia in a patient who was ultimately diagnosed with T-cell/histiocyte-rich B-cell lymphoma. A 69-year-old male patient presented to our hospital with nausea, vomiting, weakness and unintentional weight loss. His initial blood tests showed a serum calcium level of 16.1 mg/dL and serum creatinine level of 3.25 mg/dL. He had high intact parathyroid hormone (PTH, 6.8 pg/mL), mildly elevated 25-hydroxyvitamin D and serum PTH-related peptide (PTHrP). To exclude malignancy, computed tomography (CT) scans of the chest, abdomen and pelvis were performed which were unremarkable. A bone marrow biopsy was performed to detect any hidden hematologic malignancy which showed large mononuclear cells with prominent nucleoli and occasional Reed-Sternberg cells, consistent with the diagnosis of THRLBCL. Subsequent positron emission tomography demonstrated diffuse fluorodeoxyglucose (FDG) uptake. This case reports a unique presentation of a rare subtype of non-Hodgkin's lymphoma. We highlight the importance of pursuing a thorough workup for causes of hypercalcemia as well as understanding the underlying mechanisms of severe hypercalcemia in malignancy.

Clinical features and survival of patients with T-cell/histiocyte-rich large B-cell lymphoma: analysis of the National Cancer Data Base

Using data from the National Cancer Data Base, 2010-2015, we examined characteristics and outcomes of T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL, N = 622) relative to unspecified diffuse large B-cell lymphoma (DLBCL-NOS, N = 91,588) and nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL, N = 2240). Socio-demographic characteristics of patients with THRLBCL resembled more NLPHL than DLBCL-NOS. Five-year overall survival in THRLBCL was 66% (95% confidence interval [CI], 60-71%). Adjusting for clinical and socio-economic covariates, THRLBCL was associated with better survival than DLBCL-NOS (adjusted hazard ratio, 0.80; 95%CI, 0.67-0.94). This association was similar in academic and community hospitals and consistent in a model stratified by the revised International Prognostic Index. Prognostic factors in THRLBCL included age, comorbidity index, and extranodal primary site, but not stage. Adjusted odds of prior NLPHL were 18.2 higher for THRLBCL (95%CI, 7.2-45.7) than DLBCL-NOS. These large-scale epidemiologic data support the relationship between THRLBCL and NLPHL, and suggest improved prognosis with modern rituximab-based immunochemotherapy.

T-cell/Histiocyte-rich Large B-cell Lymphoma of the Larynx in a Juvenile Japanese Macaque (Macaca fuscata)

An 11-month-old female Japanese macaque (Macaca fuscata), born in captivity in a research institute, suddenly died without clinical signs. Necropsy examination revealed a nodular mass protruding from the left ventral aspect of the larynx, compressing the epiglottis anteriorly. Histopathologically, the laryngeal mass was comprised of medium- to large-sized atypical cells. Immunohistochemically, these were positive for CD20 and partially positive for CD79α. Among the atypical cells were CD3⁺ T cells and CD68⁺ histiocytes. Based on the findings, this case was diagnosed as T-cell/histiocyte-rich large B-cell lymphoma. Epstein-Barr virus (EBV)-encoded small RNAs were frequently detected in the atypical cells by in-situ hybridization, which was consistent with the finding that the macaque was seropositive for EBV antigen. This is the first report showing the potential association of simian lymphocryptovirus, the simian homologue of EBV, with lymphoma in a juvenile non-human primate.

Diagnosis of Hodgkin lymphoma in the modern era

The Hodgkin lymphomas are a family of unique lymphoma subtypes, in which the nature of the neoplastic cell was enigmatic for many years. Much of the mystery has been solved, with all forms now considered to be of B-cell origin, in most cases of germinal centre derivation. Today we recognize Hodgkin lymphoma as an eponym that encompasses multiple entities. One of the unifying themes is the major contribution from the tumour microenvironment. Both the character of the neoplastic cells and the nature of the immune environment are critical to accurate diagnosis. Moreover, an understanding of the molecular alterations that characterize both the neoplastic cells and their microenvironment have led to therapeutic advances, targeting both neoplastic and reactive components. Other conditions may foster a similar inflammatory milieu and lead to lymphoproliferations that mimic the Hodgkin lymphomas. In this review we provide an update on the diagnostic features of the various subtypes and include additional information relevant for prognostic evaluation and investigation of potential therapeutic targets. Additionally, we also discuss those conditions that often cause confusion in diagnosis and need to be distinguished from the Hodgkin lymphomas.

T-cell/histiocyte-rich large B-cell lymphoma in a child: A case report and review of literature

T-cell/histiocyte-rich large B-cell lymphoma is uncommon in children population. There were few cases reported in the literature with wide range clinical presentations including advanced stage, and more involvement of liver, spleen and bone marrow. Head and neck lymphadenopathy tends to present in younger children. We report a case of 10-year-old boy who initially presented intermittent fever, headaches and neck lymphadenopathy. Subsequently, he developed diffuse lymphadenopathy and hepatosplenomegaly. T-cell/histiocyte-rich large B-cell lymphoma was diagnosed on a cervical lymph node biopsy. Cervical lymphadenopathy in this age group is most commonly reactive or non-malignant processes. Lymphoma is much less frequent; mainly are non-Hodgkin lymphomas. However, a subset of large B-cell lymphoma called T-cell/histiocyte- rich B-cell lymphoma is rare in children.

J chain and myocyte enhancer factor 2B are useful in differentiating classical Hodgkin lymphoma from nodular lymphocyte predominant Hodgkin lymphoma and primary mediastinal large B-cell lymphoma

Although most classical Hodgkin lymphomas (CHLs) are easily distinguished from nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and primary mediastinal large B-cell lymphoma (PMBL), cases with significant CD20 expression cause diagnostic confusion. Although the absence of OCT-2 and BOB.1 are useful in these circumstances, a variable proportion of CHLs are positive for these antigens. We investigated the utility of J chain and myocyte enhancer factor 2B (MEF2B) in the diagnosis of CHL; NLPHL; PMBL; T-cell/histiocyte-rich large B-cell lymphoma (TCRLBL); and B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and CHL, compared with OCT-2 and BOB.1. J chain and MEF2B highlighted lymphocyte predominant (LP) cells in 20/20 (100%) NLPHLs and were negative in 43/43 (100%) CHLs. Fourteen of 15 (93%) PMBLs and 4/4 (100%) TCRLBLs were MEF2B positive, whereas 67% of PMBLs and 50% of TCRLBLs were J chain positive. Three of 3 B-cell lymphomas, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and CHL, were negative for J chain and MEF2B. J chain and MEF2B were 100% sensitive and specific for NLPHL versus CHL. MEF2B was 100% sensitive and 98% specific for PMBL versus CHL. Whereas loss of OCT-2 and/or BOB.1 expression had a sensitivity of only 86% and specificity of 100% for CHL versus NLPHL, PMBL, and TCRLBL, lack of both J chain and MEF2B expression was 100% sensitive and 97% specific. J chain and MEF2B are highly sensitive and specific markers of NLPHL versus CHL; are particularly useful in highlighting LP cells; and, with rare exception, are of greater utility than OCT-2 and BOB.1 in differentiating CHL from NLPHL and other large B-cell lymphomas.

Pancreatic T/histiocyte-rich large B-cell lymphoma: A case report and review of literature

Primary pancreatic lymphoma (PPL) is an extremely rare form of extranodal malignant lymphoma. The most common histological subtype of PPL is diffuse large B cell lymphoma (DLBCL). In rare cases, PPL can also present as follicular lymphoma, small lymphocytic lymphoma, and T cell lymphoma either of non-Hodgkin’s lymphoma or of Hodgkin’s lymphoma. T-cell/histiocyte-rich large B-cell lymphoma (T/HRBCL) is an uncommon morphologic variant of DLBCL with aggressive clinical course, it is predominantly a nodal disease, but extranodal sites such as bone marrow, liver, and spleen can be involved. Pancreatic involvement of T/HRBCL was not presented before. Herein, we report a 48-year-old male who was hospitalized with complaints of jaundice, dark brown urine, pale stools, and nausea. The radiological evaluation revealed a pancreatic head mass and, following operative biopsy, the tumor was diagnosed as T/HRBCL. The patient achieved remission after six cycles of CHOP chemotherapy. Therefore, T/HRBCL can be treated similarly to the stage-matched DLBCL and both of them get equivalent outcomes after chemotherapy.

Atypical variants of nodular lymphocyte-predominant Hodgkin lymphoma show low microvessel density and vessels of distention type

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) presents different histopathologic growth patterns, including atypical forms showing overlapping histopathologic and clinical features with T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL). Because growth patterns are associated with vessel distribution, the aim of the present study was to compare angiogenesis in different NLPHL patterns with THRLBCL as well as other lymphomas. Atypical variants of NLPHL and THRLBCL (n=10 per group) both showed a low microvessel density (MVD; 1.16-1.31/μm²) with a diffuse vessel distribution. In contrast, in typical NLPHL (n=10), follicular areas with low MVD were retained, whereas an increase in vessels in the interfollicular areas was observed (MVD 1.35/μm²). THRLBCL and typical NLPHL could additionally be distinguished by differences in their molecular angiogenesis signature. Furthermore, the number of intravascular T cells was significantly reduced in THRLBCL (0.0028 T cells/mm² vessel area) when compared with typical NLPHL (0.0059 T cells/mm² vessel area), potentially reflecting the different composition of the microenvironment in these 2 lymphoma entities. The results of our study reveal a similar vascular pattern and angiogenesis behavior in atypical NLPHL variants and THRLBCL in contrast to the retained follicular pattern in typical NLPHL.

T-Cell/Histiocyte-Rich Large B-Cell Lymphoma Presenting as a Primary Central Nervous System Lymphoma

Primary central nervous system (PCNSL) lymphoma is an aggressive extranodal non-Hodgkin lymphoma, and most cases are classified as diffuse large B-cell lymphoma (DLBCL) by histology. T-cell/histiocyte-rich large B-cell lymphoma (TCRLBCL) represents a distinct subtype of diffuse large B-cell lymphoma and is characterized by the presence of scattered large neoplastic B-cells in a background of abundant T-cells and histiocytes. This is in contrast to the dense perivascular cuffing of neoplastic B-cells in classic DLBCL. T-cell/histiocyte-rich large B-cell lymphoma should be considered in PCNSL cases in which neoplastic B-cells are sparse and scattered. Immunohistochemistry will help identify the B-cells and surrounding infiltrate rich in Tlymphocytes and histiocytes. Future studies exploring the biology of TCRLBCL and the crosstalk between the neoplastic cells and the surrounding inflammatory infiltrate may provide exciting prospects for future therapies for TCRLBCL.