Intravascular Large T-cell or NK-cell Lymphoma: A Rare Variant of Intravascular Large Cell Lymphoma With Frequent Cytotoxic Phenotype and Association With Epstein-Barr Virus Infection

Incidence, Prognostic Factors, and Treatment Impact on Survival in Natural Killer/T-Cell Lymphoma: Population-Based Study in the United States

Background

Natural killer/T-cell lymphoma (NKTL) is a rare malignancy of mature natural killer/T-cells, predominantly found in Asian and South/Central American populations, with limited studies conducted in Europe and the United States.

Objective

The aim of this study is to present an overview of the incidence rate, demographic and clinical characteristics, treatment options, overall survival (OS), and factors influencing OS of NKTL in the United States.

Methods

We used data from the Surveillance, Epidemiology, and End Results 17 database to analyze NKTL cases recorded between 2000 and 2020. In a cohort of 1162 patients with NKTL, we calculated the incidence rates and performed statistical analyses to evaluate OS, the effect of radiotherapy and chemotherapy on survival, and lymphoma-specific survival.

Results

The mean annual incidence rate of NKTL in the United States was 0.067 per 100,000, with higher rates observed in men compared to women, and an increase noted with age. However, there has been no significant rise in incidence over recent years. Significant racial disparities were observed, with higher incidence rates in non-Hispanic Asian or Pacific Islanders and Hispanic people. The median survival time for patients with NKTL was 21 months, with a 5-year OS rate of 39.5%, which has shown improvement in recent years. Key independent prognostic factors impacting patient survival included age at diagnosis, clinical stage, nasal type presentation, presence of systemic symptoms, and treatment modality. Patients receiving combined radiotherapy and chemotherapy exhibited the best outcomes, with a median OS of 138 months and a 5-year OS rate of 58%. This survival benefit remained consistent even in patients with stage I/localized nasal type lymphoma, achieving a 5-year OS rate of 73.3%.

Conclusions

The incidence of NKTL has remained stable in recent years. Patients with the nasal type generally experience better survival outcomes. The use of combined radiotherapy and chemotherapy appears to enhance survival, though further validation through prospective multicenter clinical trials is necessary.

Long-term remission in a patient with NK/T cell intravascular lymphoma with autologous hematopoietic cell transplantation

Intravascular lymphoma (IVL) is a rare subtype of lymphoma, mostly of B-cell origin. A few cases of IVL have been reported as having NK/T cell origins (IVNKTL). These cases are known to be fatal, especially when systemic symptoms are present. We report the case of a patient of IVNKTL who was refractory to initial treatment and received autologous hematopoietic stem cell transplantation (auto-HSCT). She has maintained complete remission (CR) for over eight years. Our case might support the evidence of auto-HSCT for the treatment of IVNKTL with chemosensitivity.

Fifth Edition of the World Health Organization Classification of Tumors of the Hematopoietic and Lymphoid Tissues: Mature T-Cell, NK-Cell, and Stroma-Derived Neoplasms of Lymphoid Tissues

This review focuses on mature T cells, natural killer (NK) cells, and stroma-derived neoplasms in the fifth edition of the World Health Organization classification of hematolymphoid tumors, including changes from the revised fourth edition. Overall, information has expanded, primarily due to advancements in genomic understanding. The updated classification adopts a hierarchical format. The updated classification relies on a multidisciplinary approach, incorporating insights from a diverse group of pathologists, clinicians, and geneticists. Indolent NK-cell lymphoproliferative disorder of the gastrointestinal tract, Epstein-Barr virus-positive nodal T- and NK-cell lymphoma, and several stroma-derived neoplasms of lymphoid tissues have been newly introduced or included. The review also provides guidance on how the fifth edition of the World Health Organization classification of hematolymphoid tumors can be applied in routine clinical practice.

Insulin-like Growth Factor II mRNA-binding Protein 3 is a Highly Sensitive Marker for Intravascular Large B-cell Lymphoma: Immunohistochemical Analysis of 152 Pathology Specimens From 88 Patients

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of aggressive extranodal large B-cell lymphoma characterized by the selective growth of lymphoma cells within the lumina of blood vessels, particularly capillaries. IVLBCL lacks mass formation, and its diagnosis can be challenging. We analyzed the utility of insulin-like growth factor II mRNA-binding protein 3 (IMP3) immunohistochemistry for IVLBCL diagnosis in various organs. Double staining with paired box 5 (PAX5) was performed for validation. Overall, 152 pathological specimens (111 positive and 41 negative for IVLBCL) obtained from 88 patients with a diagnosis of IVLBCL were stained for IMP3 and IMP3/PAX5. As negative controls, 40 pathology specimens from 38 patients with no history of IVLBCL or other B-cell lymphomas were stained for IMP3, which comprised 31 benign pathological specimens from 29 patients in whom malignancy was suspected, 7 cases of appendicitis with intravascular and/or intralymphatic lymphoid proliferations, and 2 cases of intravascular natural killer/T-cell lymphoma. All mononuclear cells with cytoplasmic staining were considered positive for IMP3 expression, but expression restricted to germinal center B cells was excluded from evaluation. All 111 IVLBCL pathological specimens were positive for IMP3 and IMP3/PAX5. In addition, 11 of the 41 specimens originally diagnosed as IVLBCL-negative showed IMP3/PAX5 double-positive cells, raising the suspicion of IVLBCL. However, of the 40 negative control samples, IMP3-positive non-germinal center B cells were detected in only 2 samples ( P = 0.0131) and no intravascular IMP3-positive B cells suspicious for IVLBCL were identified. Altogether, IMP3 immunohistochemistry is a highly sensitive marker of IVLBCL and can be a helpful adjunct for IVLBCL diagnosis.

Barking up the wrong tree: Vascular tree-in-bud due to intravascular lymphoma

A 59-year-old previously healthy woman presented with a six-month history of fever, nonproductive cough, and weight loss. The cause of these symptoms remained obscure despite a thorough, month-long hospitalization. On presentation, she was normotensive with a pulse of 98 beats/minute, respiratory rate of 20 breaths/minute, and a temperature of 39.4C. She was emaciated. Physical examination was notable for faint bibasilar crackles on lung auscultation. Initial laboratory testing revealed pancytopenia. Peripheral smear demonstrated normocytic, normochromic anemia without immature cells or schistocytes. Other notable laboratory findings included elevated levels of lactate dehydrogenase, elevated ferritin, and elevated levels of fasting serum triglycerides. A comprehensive laboratory evaluation for connective tissue disease was negative. Plain chest radiography was normal while computed tomography (CT) of the chest demonstrated sub-centimeter nodules in a branching centrilobular pattern as well as in a peri-lymphatic distribution without associated lymphadenopathy or organomegaly. The above constellation of laboratory abnormalities raised concern for hemophagocytic lymphohistiocytosis (HLH). Soluble IL-2 (CD25) receptor levels were markedly elevated. Bronchoscopy with transbronchial biopsies of the right lower lobe was performed, revealing intravascular lymphoma associated with HLH. Our case emphasizes the need for clinicians to consider vascular causes of tree - in-bud nodules in addition to the conventional bronchiolar causes. The case also is a reminder of the need to conduct an exhaustive search for malignancy, in patients with HLH.

Cutaneous Intravascular Hematolymphoid Entities: A Review

Intravascular lymphomas are rare disease conditions that exhibit neoplastic lymphoid cells that are confined mainly to the lumens of small capillaries and medium-sized vessels. The majority of the intravascular lymphomas are of B-cell origin, but they can include NK/T-cell and CD30+ immunophenotypes. In the histologic differential diagnosis are benign proliferations such as intralymphatic histiocytosis and intravascular atypical CD30+ T-cell proliferation. In this review, we discuss the clinical, histopathologic, and molecular findings of intravascular B-cell lymphoma, intravascular NK/T-cell lymphoma, intralymphatic histiocytosis, and benign atypical intravascular CD30+ T-cell proliferation.

A Comparison of the Fifth World Health Organization and the International Consensus Classifications of Mature T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a rare subset of non-Hodgkin lymphomas that often carry significant difficulty in diagnosis and classification because of their rarity and biological complexity. Previous editions of the World Health Organization (WHO) classifications of hemopoietic neoplasms in 2001, 2008, and 2017 aimed to standardize hemopoietic neoplasm diagnosis in general. Since then, crucial clinico-pathological, immunophenotypic, and recent molecular discoveries have been made in the field of lymphomas, contributing to refining diagnostic criteria of several diseases, upgrading entities previously defined as provisional, and identifying new entities. In 2022, two different models were proposed to classify hematolymphoid neoplasms: the 5th edition of the WHO classification (WHO-HAEM5) and the International Consensus Classification (ICC). Of note, a common nosography is mandatory to ensure progress in health science and ensure the basis for a real precision medicine. In this article, the authors summarized the main differences with the previous fourth WHO edition and reviewed the main discrepancies between the two newest classifications, as far as PTCLs are concerned.

Intravascular NK/T-Cell Lymphoma: What We Know about This Diagnostically Challenging, Aggressive Disease

Intravascular lymphoma is a form of lymphoid malignancy characterized by neoplastic cells growing almost exclusively within the lumina of small- to medium-sized blood vessels. Most cases are of B-cell origin with rare cases of natural killer or T-cell lineage. Extranodal sites are affected, mainly the skin and central nervous system, although any organ may be involved. Intravascular NK/T-cell lymphoma deserves special attention because of its clinicopathologic features and the need for adequate immunophenotyping combined with clonality test for a proper diagnosis. Moreover, intravascular NK/T-cell lymphoma is strongly linked to Epstein-Barr virus (EBV), which is considered to play a role in tumorigenesis and to be responsible for the aggressive behavior of the disease. In this paper, we review the current knowledge on this rare lymphoma and, in particular, the most recent advances about its molecular landscape. The main distinguishing features with other EBV-related entities, such as extranodal NK/T-cell lymphoma, EBV-positive primary nodal T/NK-cell lymphoma, and aggressive NK-cell leukemia, are discussed to help pathologists obtain the correct diagnosis and consequently develop an adequate and prompt therapy response.

The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Lymphoid Neoplasms

We herein present an overview of the upcoming 5^th edition of the World Health Organization Classification of Haematolymphoid Tumours focussing on lymphoid neoplasms. Myeloid and histiocytic neoplasms will be presented in a separate accompanying article. Besides listing the entities of the classification, we highlight and explain changes from the revised 4^th edition. These include reorganization of entities by a hierarchical system as is adopted throughout the 5^th edition of the WHO classification of tumours of all organ systems, modification of nomenclature for some entities, revision of diagnostic criteria or subtypes, deletion of certain entities, and introduction of new entities, as well as inclusion of tumour-like lesions, mesenchymal lesions specific to lymph node and spleen, and germline predisposition syndromes associated with the lymphoid neoplasms.

Clinical Characteristics, Prognostic Indicators, and Survival Outcomes in Intravascular Lymphoma: Mayo Clinic Experience (2003-2018)

Intravascular lymphoma (IVL) is a rare extranodal non‐Hodgkin lymphoma. We performed a retrospective analysis of 55 IVL patients who were treated at our institution 2003–2018. Median age at diagnosis was 68 years, and 64% were males. The most frequent presenting symptoms were skin rash 43% and weight loss 30%. MRI brain on IVL patients with CNS involvement (CNS‐IVL) showed multifocal involvement in 76% (13/17). 89% (17/19) of non‐CNS‐IVL patients with abnormal FDG‐PET had biopsy of an avid lesion resulting in definitive diagnosis. The top diagnostic biopsy site was the bone marrow (45%). 56% had multiorgan involvement. Based on CNS involvement, 36.5% (20/55) had CNS‐IVL and 63.5% (35/55) had non‐CNS‐IVL. CNS‐IVL group consists of clinically isolated CNS involvement (CNS‐only IVL) (22%;12/55) and mixed clinical CNS and peripheral site involvement (M‐IVL) (14.5%; 8/55). Non‐CNS‐IVL group consists of clinically isolated skin involvement (skin‐only IVL) (9%; 5/55) and peripheral IVL with or without skin involvement (P‐IVL); (54.5%; 30/55). Skin involvement was predominantly in the lower extremities. Pathologically, 89% (48/54) were B‐cell IVL. Rituximab + high‐dose methotrexate‐based regimen were used in 75% (12/16) of CNS‐IVL patients and RCHOP in 60% (17/28) of non‐CNS‐IVL patients. Estimated 5‐year progression free survival (PFS) and overall survival (OS) for the entire cohort were 38.6% and 52%, respectively. Skin‐only IVL was associated with excellent survival. Platelet count <150x10⁹/L, age > 60Y, and treatment without Rituximab were poor prognostic factors. Further research is necessary to identify novel therapies.

Reactive Intralymphovascular Immunoblastic Proliferations Mimicking Aggressive Lymphomas

Reactive intralymphovascular immunoblastic proliferations (ILVIPs) may mimic aggressive lymphomas and are rarely reported. Herein, we characterize the clinicopathologic features of 8 patients with ILVIPs. No patients had lymphadenopathy, hepatosplenomegaly, or other findings suggestive of lymphoma. The ILVIPs involved the small or large intestine (n=5) and appendix (n=3). Patients were evaluated for abdominal pain, suspected appendicitis, intestinal obstruction, diverticulitis, volvulus, or tumor resection. Histologic sections showed expanded lymphovascular spaces filled by intermediate to large immunoblasts, positive for CD38, CD43, CD45, CD79a, and MUM1/IRF4 in all cases tested. Five of 6 (83%) cases were positive for CD30. CD20 was weakly positive in a subset of cells in 2 (25%) cases, and PAX5 was weakly positive in 4 (50%) cases. The immunoblasts expressed polytypic light chains in all cases tested. In 1 case, a subset of immunoblasts expressed T-cell markers indicating the presence of a T-cell component. The immunoblasts were negative for ALK, BCL-2, BCL-6, CD10, CD56, CD138, and Epstein-Barr virus-encoded small RNA in all cases assessed. The proliferation index shown by Ki-67 was high with a median of 80%. In all 6 cases tested, the immunoblasts were shown within lymphatic channels highlighted by D2-40. In conclusion, ILVIPs can be rarely observed in patients with inflammatory or infectious conditions, especially in gastrointestinal tract surgical specimens. The immunoblasts are predominantly of B-lineage with a postgerminal center immunophenotype and are located within lymphatic channels. It is essential to distinguish reactive ILVIPs from aggressive lymphomas to avoid unnecessary therapy.

CUTANEOUS B-CELL LYMPHOMAS: UPDATE ON DIAGNOSIS, RISK-STRATIFICATION, AND MANAGEMENT

PCBCLs are a group of Non-Hodgkin's B-cell lymphomas originating in and usually confined to the skin, representing approximately one fourth of primary cutaneous lymphomas (PCL). Their current classification system has been the result of the joint World Health Organization (WHO) - European Organization for Research and Treatment of Cancer (EORTC) consensus in 2018. To date, several types of PCBCLs have been described in the scientific literature, with different clinical presentation and prognosis. Primary cutaneous follicle-center lymphoma (PCFCL) and primary cutaneous marginal zone lymphoma (PCMZL) are the most common forms, with a typical indolent course. On the contrary, primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL, LT) is less common, yet more aggressive, with a reported 5-year overall survival of approximatively 50%. In this review, we outline the PCBCLs defining diagnostic criteria, report the features of the less common subtypes and summarize the noteworthy therapeutical options currently available in this field.

What Effect Does Epstein-Barr Virus Have on Extranodal Natural Killer/T-Cell Lymphoma Prognosis? A Review of 153 Reported Cases

The primary aim of this review is to identify the relationship between Epstein-Barr virus (EBV) and prognosis in extranodal natural killer/T-cell lymphoma (ENKTL). Additionally, a literature review of ENKTL was carried out. The investigators designed and implemented a 21-year literature review using the online databases PubMed and Google Scholar. The total number of cases analyzed was 153 (64 case reports; one comparative study; one systematic review). Information related to ENKTL from July 1999 to February 2021 was included in the study. Study variables included: patient demographics, tumor classification, screening modalities, tumor characteristics, symptomatology, treatment, and prognosis. The average age at diagnosis was 50.9 years (range: 4-90 years). Patients of Asian ethnicity were most commonly affected, and there was a 1.6:1 male to female ratio. ENKTL was most frequently detected in the head and neck region, and 53.1% of cases metastasized. Of all head and neck cases, the nose was the most affected location. Immunohistochemistry positivity included: EBV (32.0%), CD2 (96.6%), CD3ϵ (81.7%), CD43 (91.7%), CD56 (86.4%), Granzyme (97.1%), Perforin (90.9%), TIA-1 (97.8%), p53 (33.3%). The most frequently employed single treatment modality was chemotherapy alone, and 34.2% of patients expired within five years of diagnosis. The average follow-up period was 16.51 months (range: 0.25-66 months). EBV was significantly associated with metastatic ENKTL (χ² = 4.36; CV = 3.84; p = 0.037). We found no association between EBV and ENKTL prognosis (χ² = 17.2; CV = 21.0; p = 0.14).

[Clinicopathological features of intravascular peripheral T-cell lymphoma]

Objective: To summarize the clinical and pathological features of intravascular NK and T cell lymphoma for better understanding of such disease to reduce misdiagnosis and miss-diagnosis. Methods: Clinical and pathological features were analyzed retrospectively in one case of intravascular peripheral T-cell lymphoma, not otherwise specified (IVPTCL, NOS) , with literatures review. Results: The case presented in this study was a 66-year-old man. PET/CT scan showed multiple lymph nodes enlargement throughout the body. Normal lymph node structure could not be observed by tissue biopsy, while lymph follicles were partially disrupted. High-power light microscope revealed a large number of blood vessels with diffuse proliferation and dilation, where atypical lymphoid cell mass was restricted in the lumen and partially infiltrated the large blood vessel wall. These tumor cells were medium to large with moderate cytoplasm. The nucleus was irregular, single or multiple nucleoli could be seen, chromatin was condensed, some were empty and bright, and mitotic figures could be seen. Immunohistochemical staining showed that the neoplastic cells were positive for expression of CD3, CD43, CD8, GrB, TIA-1 and perforin. EBER in situ hybridization result was negative. Polymerase chain reaction test identified a clonal gene rearrangement of T-cell receptor γ. The patient was treated with CHOP in combination with chidamide, but died of infection and cardiopulmonary failure within 2 months. 56 cases of intravascular NK/T cell lymphoma with definite classification were collected from relevant literatures, including 47 cases with nasal type of extranodal NK/T cell lymphoma (27 were male and 20 were female) , 8 cases with anaplastic large cell lymphoma (3 males and 5 females) , and only one case with de nova IVPTCL, NOS in brain. We report the second case of IVPTCL,NOS, and notably originated from lymph node for the first time. Conclusions: Intravascular NK/T cell lymphoma is a highly aggressive disease with no effective treatment at present. Involvement of Lymph node has rarely been reported, and further studies on more cases are necessary.

Intravascular pseudolymphomatous angiosarcoma: A new finding potentially mistaken for intravascular lymphoma

Pseudolymphomatous infiltrates associated with angiosarcoma are a rarely reported phenomenon. Recognition of this reactive process is critical to making an accurate diagnosis, both in diagnosing the angiosarcoma and in avoiding an incorrect diagnosis of lymphoma. Here, we present a novel histopathologic pattern, angiosarcoma with a prominently intravascular atypical lymphoid component, mimicking intravascular T-cell lymphoma. Interestingly, serial biopsies in this case revealed a progressive increase in lymphocyte density and intravascular component over time. Despite prior reports of improved progression-free survival and overall survival of patients with pseudolymphomatous angiosarcoma, this patient showed rapid disease progression.

Case of Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type, Presenting With Intravascular Localization of Tumor Cells in Skin Biopsies From Both Plaque and Normal-Appearing Skin: A Case Report and Literature Review

Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL-NT), is a rare subtype of non-Hodgkin lymphoma associated with Epstein-Barr virus. This type of lymphoma is rare in Western countries but is more frequent in East Asia and Latin America. ENKTL-NT mostly occurs in the nose and paranasal area, including the upper aerodigestive tract. The skin is the second-most commonly involved organ. ENKTL-ET is characterized by an angiocentric, angiodestructive pattern of growth with ulceration and necrosis evident on histopathological examination. We provide the first description of ENKTL-NT presenting with intravascular localization of tumor cells in skin biopsies from both plaque and normal-appearing skin. Random skin biopsy might thus be useful for early diagnosis, staging, and estimation of prognosis in ENKTL-NT. Moreover, the current case indicates that ENKTL-NT and intravascular natural killer/T-cell lymphoma may represent related diseases.

Cytogenetic complexity and heterogeneity in intravascular lymphoma

AIMS

To characterise the karyotypic abnormalities and heterogeneities in intravascular lymphoma (IVL).

METHODS

G-banded karyotyping was performed on biopsy specimens from a single-centre IVL cohort comprising intravascular large B-cell lymphoma (IVLBCL, n=12) and NK/T-cell lymphoma (IVNKTCL, n=1).

RESULTS

Five IVLBCL cases and one IVNKTCL case (total 46%) were found to have normal karyotypes, and the cytogenetic abnormalities observed in the other seven IVLBCL cases (54%) were investigated further. These seven karyotypes were uniformly complex with an average of 13 aberrations. The seven cases all had abnormalities involving chromosome 6, with 57% involving structural abnormalities at 6q13, and chromosome 8, with 43% involving abnormalities at 8p11.2. In addition, 71% had aberrations at 19q13. On average, 4.4 chromosomal gains and losses were detected per case. Cytogenetic heterogeneities were observed in six cases (86%) and tetraploidy in three cases (43%). There was no significant difference in progression-free survival (p=0.92) and overall survival (p=0.61) between the IVLBCL cases with complex and normal karyotypes.

CONCLUSION

Approximately half of IVLBCL cases had a highly heterogeneous pattern of karyotypes with different clonal numerical and structural chromosome aberrations.

Analysis of clinicopathological features and prognostic factors of non-Hodgkin's intravascular large B-cell lymphoma

Non-Hodgkin's intravascular large B-cell lymphoma is a highly invasive extranodal lymphoma. The proliferating tumor cells invade the small vessels and capillaries of different organs. The clinical symptoms are atypical, there is lack of specificity, and the molecular and biological behaviors are not clear, thus, the present study aimed to improve the current understanding of non-Hodgkin's intravascular large B-cell lymphoma (IVL) and provide an accurate basis for clinical treatment and prognosis, by retrospectively analyzing and summarizing the clinicopathological features, immunohistochemical findings and molecular characteristics of 17 patients with IVL. The Kaplan-Meier method and log rank test were implemented to determine survival outcomes. Fisher's exact test was used to determine the association between clinicopathological features and the expression levels of Ki-67, c-Myc, B-cell lymphoma 6 (Bcl-6) and B-cell lymphoma 2 (Bcl-2), while multivariate Cox regression analysis was performed to identify the independent risk factors that affect the survival rates of patients with IVL. P<0.05 was considered to indicate a statistically significant difference. Among the 17 patients with IVL, 13 cases (76.47%) occurred in the adrenal gland and four cases (23.53%) occurred on the skin demonstrated positive IgH gene rearrangement. FISH analysis indicated that cleavage of the c-Myc gene was closely associated with sex, hypertension status and tumor size, while cleavage of the Bcl-6 gene was closely associated with tumor size parameters. Overall, the results suggest that the Ki-67 proliferation index is an independent risk factor for the prognosis (survival time) of patients with IVL.

Transcriptome complexity in intravascular NK/T-cell lymphoma

AIMS

Intravascular NK/T-cell lymphoma (IVNKTCL) is a rare disease, which is characterised by exclusive growth of large cells within the lumen of small vessels, Epstein-Barr virus infection and somatic mutations in epigenetic regulator genes. Here, we elucidate the transcriptomic complexity of IVNKTCL.

METHODS

IVNKTCL cases were retrieved from a single-centre cohort of 25 intravascular lymphomas. RNA-seq and whole exome sequencing (WES) were performed to analyse transcriptomic abnormalities and mutations in splicing factors.

RESULTS

Approximately 88% of the total reads from the RNA-seq were considered exonic, while the remaining reads (12%) were mapped to intronic or intergenic regions. We detected 28,941 alternative splicing events, some of which would produce abnormal proteins rarely found in normal cells. The detected events also included tumour-specific splicing alterations in oncogenes and tumour suppressors (e.g., HRAS, MDM2 and VEGFA). WES identified premature termination mutations or copy number losses in a total of 15 splicing regulator genes, including SF3B5, SRSF12 and TNPO3.

CONCLUSIONS

This study raises the possibility that IVNKTCL may be driven by multiple complex regulatory loops, including non-exonic expression and aberrant splicing, in addition to defects in epigenetic regulation.

Intravascular NK/T-cell lymphoma, Epstein-Barr virus positive with multiorgan involvement: a clinical dilemma

Background

Intravascular lymphoma is a rare type of non-Hodgkin lymphoma mostly of B-cell lineage. A few cases of intravascular lymphoma have been found to be of NK/T-cell origin, mainly affecting the skin and central nervous system.

Case presentation

A 54-year-old Caucasian man sought care because of a 2 weeks history of jaundice and intermittent fever, not responsive to antibiotics and antipyretics. Laboratory tests showed low blood oxygen concentration and pancytopenia. Serum microbiological tests were negative. Computerized tomography (CT) scan revealed hepatosplenomegaly and diffuse ground-glass opacities in both lungs without interlobular septal thickening. Despite oxygen therapy, the clinical conditions rapidly deteriorated leading to death 3 days after admission. Autopsy revealed a multiorgan involvement by an Epstein-Barr virus positive NK/T-cell lymphoma, strikingly growing within the blood vessel lumina, in absence of skin lesions.

Conclusions

The current case highlights the pathological features of this rare entity, the protean clinical presentation of which is often misleading, resulting in delayed diagnosis and treatment.

[Clinical and pathological characteristics of intravascular lymphomas]

Intravascular B‑cell lymphomas (IVL) are rare neoplasms that can manifest at any age (mean age ~62-63 years). About half of the cases are associated with Epstein-Barr virus. The most common sites of manifestation are the brain, skin, and bone marrow. The diagnosis is difficult due to unspecific clinical presentation and laboratory changes. FACS (fluorescence-activated cell sorting) and clonality analysis from peripheral blood and radiological findings are often not diagnostic. The most sensitive and most specific diagnostic method is the histopathological and immunohistochemical evaluation of a tissue biopsy. Because of the rarity of this disease, little is known about therapy and prognosis, whereby therapy is mainly similar to non-IVL lymphomas. The prognosis is poor; median survival after diagnosis is approximately one year.

Molecular classification of tumour cells in a patient with intravascular large B-cell lymphoma

BACKGROUND

Intravascular large B-cell lymphoma (IVLBCL) is a rare type of extranodal LBCL. It is characterized by the proliferation of tumour cells exclusively intraluminally in small blood vessels of different organs. The clinical manifestation depends on the type of organ affected; additionally, a haemophagocytic syndrome can be observed in some patients.

OBJECTIVES

The aim was to further understand the nosology of this lymphoma as, due to its rarity and in spite of detailed immunohistochemical investigations, its exact nosology is only incompletely understood.

METHODS

We used microarray-based analysis of gene expression of tumour cells isolated from a patient with primary manifestation of the lymphoma in the skin and compared it with various other diffuse LBCLs (DLBCLs) as well as a previously published DLBCL classifier.

RESULTS

In unsupervised analyses, the tumour cells clustered together with non-germinal centre B-cell (non-GCB) DLBCL samples but were clearly distinct from GCB-DLBCL. Analogous to non-GCB DLBCL, molecular cell-of-origin classification revealed similarity to bone-marrow derived plasma cells.

CONCLUSIONS

The IVLBCL of this patient showed molecular similarity to non-GCB DLBCL. Due to the prognostic and increasingly also therapeutic relevance of molecular subtyping in DLBCL, this method, in addition to immunohistochemistry, should also be considered for the diagnosis of IVLBCL in the future.

Unusual Presentation of a Small-Cell Variant of Anaplastic Large-Cell Lymphoma Case: When a Septic Picture Is Not Sepsis

We report a case of a small-cell variant of anaplastic large-cell lymphoma, with an unusual clinical presentation mimicking sepsis and a fulminant clinic course, in a 48-year-old Caucasian female. In this report, we discuss the diagnostic challenge, histopathologic features, and unique cytogenetic features of this case, in order to raise awareness of this rare presentation and emphasize the importance of meticulous peripheral smear examination and early bone marrow evaluation.

Intravascular T-cell lymphoma in a patas monkey (Erythrocebus patas)

A 9-year-old female captive patas monkey (Erythrocebus patas) presented with poor general condition, inability to stand, petechiae, anaemia, thrombocytopenia, and leukocytosis. Due to poor response to treatment, the animal was euthanized 16 days later. Postmortem examination revealed hemorrhages in several organs and bilateral cerebral infarctions. Histologically, prominent accumulations of large neoplastic lymphocytes in cerebral and meningeal blood vessels were demonstrated within the lesions and in other organs (e.g., bone marrow, ovary, intestine). Immunohistochemically, neoplastic cells expressed CD3 and Ki-67. PCR revealed a lymphocryptovirus (LCV) infection, while Epstein–Barr nuclear antigen 2 (EBNA2) could not be demonstrated within neoplastic cells by means of immunohistochemistry. Based on the pathological findings, an intravascular lymphoma (IVL) of T-cell origin was diagnosed. To the authors' knowledge, this is the first report on this rare entity in a nonhuman primate.

Intralymphatic Spread Is a Common Finding in Cutaneous CD30+ Lymphoproliferative Disorders

An intralymphatic variant of the cutaneous CD30 lymphoproliferative disorders (cutaneous anaplastic large cell lymphoma [ALCL] and lymphomatoid papulosis [LyP]) has been described recently. We retrieved 60 cases of ALCL of the skin (primary cutaneous: 37; cases with concomitant involvement of 1 regional lymph node: 4; skin involvement from systemic disease: 4; cases with staging results unknown: 15) and 16 cases of LyP, to evaluate the presence of lymphatic vessel involvement by neoplastic cells. A D2-40 immunohistochemical staining was used to highlight lymphatic vessels. Lymphatic vessel involvement was found in 36 cases (60%) of ALCL (primary cutaneous: 24; concomitant: 3; secondary cutaneous: 4; staging unknown: 5), and in 6 cases (37.5%) of LyP. Follow-up data, available in 28 patients with ALCL and 11 with LyP, suggested that lymphatic vessel involvement had no negative prognostic implication. Our study demonstrates that cutaneous CD30 lymphoproliferative disorders are frequently characterized by involvement of the lymphatic vessels. The intralymphatic variant of ALCL and LyP may be explained, at least in part, by a particular lymphotropism of the neoplastic cells of cutaneous CD30 lymphoproliferative disorders.

Cutaneous Involvement in a Case of Intravascular T-Cell Lymphoma With a γδ Phenotype

Intravascular lymphomas (IVL) are uncommon variants of extranodal non-Hodgkin which are usually difficult to diagnose because of their lack of clinical uniformity. Most cases are of B-cell differentiation followed by natural killer/T-cell differentiation and underlying CD30 lymphoproliferative conditions. Epstein-Barr virus is pathogenically related in most of the natural killer/T-cell variants, and the skin is a common site of presentation noted in approximately 40% of cases. Recently, cases with uncommon phenotypes have been described, expanding our understanding of the pathogenesis of this condition. In this report, we describe a 67-year-old man with a 3-month history of constitutional symptoms associated with linear purpuric macules on the trunk, pancytopenia, and high levels of serum lactate dehydrogenase. He had been followed for longstanding adenopathy and hepatosplenomegaly. Skin biopsy demonstrated a intravascular lymphocytic proliferation with positivity for CD3, CD2, CD5, and γδ T-cell receptor marker; in situ hybridization Epstein-Barr virus RNA was negative. The patient was subsequently treated with chemotherapy and allogenic stem cell transplant. He remains in complete remission 6 months posttransplant. Although the presence of hepatosplenomegaly led to consideration of a hepatosplenic T-cell lymphoma, it was pre-existing for several years making the diagnosis doubtful. To our knowledge, this is the first case report of an IVL γδ T-cell lymphoma.

Cutaneous Intravascular NK/T-cell lymphoma mimic panniculitis clinically, case report and literature brief review

Intravascular large cell lymphoma is a rare subtype of extranodal large cell lymphoma characterized by the presence of neoplastic cells within the lumina of small vessels. Most cases of intravascular large cell lymphoma have a B-cell phenotype. To date, 12 cases of intravascular natural killer (NK/)/T–cell lymphoma (IVNKL) have been reported. Our case is A 47-year-old female presented with erythematous patches and plaques on the lower extremities mimicking panniculitis clinically. A skin biopsy revealed intravascular lymphoma (IVL) with a NK/T cell phenotype (positive for CD3, and granzyme B and negative for CD20, CD4, CD8, CD5). The lymphoma cells were also positive for Epstein-Barr virus by Epstein-Barr virus-encoded RNA in situ hybridization test. Because this type of lymphoma is extremely rare, our case is documented and compared with the previously reported cases.

Intravascular NK-cell lymphoma: a case report and review of the literature

Background

Intravascular NK-cell lymphoma (IVNKL) is an extremely rare variant of non-Hodgkin lymphoma. To our knowledge, there are only a few cases reported in the English literature. Here, a case of a 29-year-old male with IVNKL involving the skin of the trunk and 4 extremities and liver is presented. A comprehensive literature review is undertaken to summarize the clinical and pathological features of this disorder.

Findings

In our case, large neoplastic lymphoid cells are restricted to the lumen of small vessels and exhibit the phenotype of a true NK cell. The morphology and immunophenotype, positivity of EBER and NK-cell origin are similar to other IVNKL cases. In addition, some cases including ours carry a poor prognosis as multiple systems or vital organs are involved.

Conclusion

In summary, we report a case of an unusual intravascular lymphoma of NK-cell lineage that displays both clinical and pathological features and compare it with other differential diagnoses. It is important to recognize this rare entity to make an appropriate diagnosis and achieve a better understanding regarding the treatment and prognosis.

Primary effusion lymphoma presenting as a cutaneous intravascular lymphoma

Primary effusion lymphoma (PEL) is a rare and aggressive lymphoma that arises in the context of immunosuppression and is characterized by co-infection with Epstein-Barr virus (EBV) and human herpesvirus-8/Kaposi sarcoma-associated herpesvirus (HHV-8/KSHV). It was originally described as arising in body cavity effusions, but presentation as a mass lesion (extracavitary PEL) is now recognized. Here, we describe a case of PEL with an initial presentation as an intravascular lymphoma with associated skin lesions. The patient was a 53-year-old man with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) who presented with fevers, weight loss and skin lesions concerning for Kaposi sarcoma (KS). A skin biopsy revealed no evidence of KS; however, dermal vessels contained large atypical cells that expressed CD31 and plasma cell markers but lacked most B- and T-cell antigens. The atypical cells expressed EBV and HHV-8. The patient subsequently developed a malignant pleural effusion containing the same neoplastic cell population. The findings in this case highlight the potential for unusual intravascular presentations of PEL in the skin as well as the importance of pursuing microscopic diagnosis of skin lesions in immunosuppressed patients.

Cutaneous lymphomas: an update. Part 2: B-cell lymphomas and related conditions

: Primary cutaneous B-cell lymphomas (PCBCL) are the second most common form of primary cutaneous lymphomas and account for approximately 25%-30% of all primary cutaneous lymphomas. Both forms of low-grade malignant PCBCL, primary cutaneous follicle center lymphoma (PCFCL) and primary cutaneous marginal zone lymphoma of mucosa-associated lymphoid tissue-type (MALT lymphoma) (PCMZL) represent the vast majority of PCBCL and show an indolent slowly progressive course and an excellent prognosis despite a high recurrence rate. Genetic analysis indicates that PCMZL differ from other forms of extranodal MALT lymphomas. The more common class-switched and the non-class-switched form of PCMZL can be distinguished as two distinctive subsets that differ in the cellular composition, IgM expression, and biological behavior with extracutaneous involvement found in the non-class-switched form. Recently, unusual clinical and histological forms of PCMZL and PCFCL manifesting with miliary or agminated lesions have been described that are diagnostically challenging. In contrast to PCMZL and PCFCL, primary cutaneous diffuse large B-cell lymphoma, leg type, and other rare forms of large B-cell lymphomas such as intravascular large B-cell lymphoma have an unfavorable prognosis. There is an emerging group of Epstein-Barr virus (EBV)-driven B-cell lymphoproliferations including posttransplant lymphoproliferative disorders and mucocutaneous ulcer occurring in immunocompromised patients and EBV-associated diffuse large B-cell lymphoma of the elderly arising in the setting of senescence-linked immunodeficiency. This review reports on recent findings expanding the spectrum of clinicopathological features, differential diagnostic aspects, and the pathogenesis of PCBCL and discusses the group of EBV-associated B-cell lymphoproliferations involving the skin.

Benign atypical intravascular CD30+ T-cell proliferation: a recently described reactive lymphoproliferative process and simulator of intravascular lymphoma: report of a case associated with lichen sclerosus and review of the literature

OBJECTIVES

Intravascular accumulations of atypical large lymphoid cells are a rare finding in skin biopsy specimens and raise the suspicion for intravascular lymphoma. The intravascular accumulation of atypical large CD30+ T cells, however, as a reactive process is very uncommon in the skin, with only four cases documented so far in the literature. This condition, referred to as benign intravascular atypical CD30+ T-cell proliferation, has been associated with chronic inflammation after trauma.

METHODS

We report on a case of atypical intravascular CD30+ T-cell proliferation in a patient with ulcerated lichen sclerosus on the foreskin, discuss the differential diagnoses, propose diagnostic criteria, and review the literature on this uncommon reactive intralymphatic CD30+ T-cell lymphoproliferation.

RESULTS

The atypical intravascular CD30+ T-cell proliferation is characterized by the accumulation of large CD30+ polyclonal T cells within lymphatics in close vicinity to ulceration or an inflammatory skin disease. There is no association with Epstein-Barr virus infection.

CONCLUSIONS

This benign cutaneous lymphoproliferation needs to be distinguished from intravascular T-cell lymphoma, particularly from the intravascular variant of anaplastic large cell lymphoma. Obstruction of lymphatics due to lichen sclerosus with disrupted immune cell trafficking may result in the accumulation of activated CD30+ lymphocytes.

Cutaneous intravascular natural killer-cell lymphoma: a case report and review of the literature

OBJECTIVES

To our knowledge, since 2003, there have been 11 reported cases of intravascular natural killer (NK)-cell lymphoma (IVNKL). Herein we describe the 12th case.

METHODS

H&E and Envision immunohistochemical stains as well as in situ hybridization were used to study this disease in combination with review of the literature.

RESULTS

Half of the cases reported to date are from China and Taipei. The clinical manifestation of IVNKL is erythema in the limbs and trunk, although patients' conditions have varied notably from each other. One-year survival rate is about 40%.

CONCLUSIONS

IVNKL should be distinguished from extranodal NK/T-cell lymphoma (nasal type) and aggressive NK-cell leukemia. These three diseases have a similar phenotype and are all related to Epstein-Barr virus infection. However, the pathogenesis of similarities and differences needs further study. In particular, IVNKL is quite unusual. The treatment of IVNKL is difficult, and the prognosis is poor. Currently, IVNKL is not included in the World Health Organization classification subtypes and has been classified into NK/T-cell lymphoma (nasal type). However, in view of the unique characteristics of this disease, we propose that the diagnosis be independent, since this will facilitate further study of this disease.

Intravascular cytotoxic T-cell lymphoma in a young immunocompetent woman

Intravascular lymphoma (IVL) is a rare disorder characterized by the presence of large neoplastic lymphoid cells restricted to the lumens of small vessels with a predilection for the skin and the central nervous system. While the vast majority of cases involving IVL are of B-cell lineage, the disease rarely affects the T-cell, the histiocytes, and the natural killer cells. We report a case of intravascular T-cell lymphoma (IVTL) associated with Epstein-Barr virus (EBV). A 23-year-old healthy woman presented with tender indurated erythematous patches with overlying telangiectasia on her right breast, abdomen, both the upper and the lower extremities and the back for 3 months. The pathology revealed an infiltration of dermal and subcutaneous vessels by large and atypical lymphoid cells with immunohistochemical features of the T-cell lineage with a cytotoxic phenotype (CD3+, CD8+, granzyme B+, TIA-1+, CD4-, CD5-, CD20-, CD56-). Interestingly, the DNA extracted from the skin biopsies demonstrated evidence of a monoclonal immunoglobulin heavy chain gene rearrangement, but no T-cell receptor gene rearrangement was found. In situ hybridization study for EBV-encoded RNA was positive. She was diagnosed with an EBV-associated IVTL. The patient's skin lesions were refractory to the combination of chemotherapy and autologous stem cell transplant, and she expired. The findings in the present case may highlight the unique clinicopathologic aspects of EBV-associated cytotoxic IVTL that occurred in a young, immunocompetent woman.

HHV-8-positive and EBV-positive intravascular lymphoma: an unusual presentation of extracavitary primary effusion lymphoma

Intravascular lymphomas are rare and aggressive hematolymphoid tumors. Here, we describe a human herpesvirus type-8 (HHV-8)/Kaposi sarcoma-associated herpesvirus-positive and Epstein-Barr virus (EBV)-positive intravascular lymphoma. The patient was a 59-year-old human immunodeficiency virus-positive man who presented with diarrhea, abdominal pain, fevers, night sweats, and weight loss. Radiographic studies of the abdomen and pelvis revealed numerous subcentimeter nodules within the subcutaneous fat that lacked connection to the skin. An excisional biopsy demonstrated large atypical cells within vessels in the deep subcutaneous fat, and many of the vessels contained extensive organizing thrombi. The atypical cells lacked strong expression of most B-cell markers but were positive for MUM-1 and showed partial expression of several T-cell markers. An immunohistochemical stain for HHV-8 and an in situ hybridization for EBV were both positive in the neoplastic cells. The disease had a rapidly progressive and fatal course. This lymphoma appears to represent an entirely intravascular form of primary effusion lymphoma and highlights the propensity for HHV-8 and EBV-positive lymphoid neoplasms to show aberrant expression of T-cell markers, illustrates the utility of skin biopsies for the diagnosis of intravascular lymphoma, and suggests that biopsies to evaluate for intravascular lymphoma should be relatively deep and include subcutaneous fat.