The clinicopathological features of extensive small intestinal CD4 T cell infiltration

Indolent CD4+ CAR T-Cell Lymphoma after Cilta-cel CAR T-Cell Therapy

Indolent CD4+ cytotoxic chimeric antigen receptor (CAR) T-cell lymphoma involving the small intestine was diagnosed in a patient who had previously received ciltacabtagene autoleucel (cilta-cel) CAR T-cell therapy for treatment of myeloma. Targeted messenger RNA sequencing revealed the presence of CAR gene product in tumor cells. Whole-genome sequencing of samples of tumor and peripheral blood identified a single lentiviral insertion site within the second intron of the SSU72 gene. In addition, numerous genetic alterations that may have contributed to malignant transformation were identified in the tumor sample. (Funded by MedStar Georgetown University Hospital.).

Indolent T-Cell/Natural Killer-Cell Lymphomas/Lymphoproliferative Disorders of the Gastrointestinal Tract-What Have We Learned in the Last Decade?

Primary gastrointestinal (GI) T-cell and natural killer (NK)-cell lymphomas/lymphoproliferative disorders (LPD) are uncommon, and they are usually aggressive in nature. However, T-cell and NK-cell lymphoma/LPD of the GI tract with indolent clinical course has been reported over the past 2 decades. Indolent T-cell LPD was formally proposed a decade ago in 2013 and 4 years later recognized as a provisional entity by the revised fourth edition of WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues in 2017. Indolent T-cell LPD of the GI tract has been changed to indolent T-cell lymphoma of the GI tract as a distinct entity by the fifth edition of WHO Classification of Haematolymphoid Tumours, but the International Consensus Classification of mature lymphoid neoplasms prefers indolent clonal T-cell LPD of the GI tract instead. In the past decade, indolent lymphoma/LPD of the GI tract has been expanded to NK cells, and as such, indolent NK-cell LPD of the GI tract was recognized as an entity by both the fifth edition of WHO Classification of Haematolymphoid Tumours and the International Consensus Classification. The underlying genetic/molecular mechanisms of both indolent T-cell lymphoma/LPD of the GI tract and indolent NK-cell LPD of the GI tract have been recently discovered. In this review, we describe the history; salient clinical, cytohistomorphologic, and immunohistochemical features; and genetic/genomic landscape of both entities. In addition, we also summarize the mimics and differential diagnosis. Finally, we propose future directions with regard to the pathogenesis and clinical management.

Immunological studies on the effects of toltrazuril and neem extract in broiler chickens suffering from coccidiosis

Background

The prevalence of avian coccidiosis in the poultry industry has grown, resulting in substantial financial losses from high mortality, stunted growth, reduced productivity, and expensive medical expenses.

Aim

The purpose of the current study was to assess the immunological effects of neem leaf extract and toltrazuril on broilers that had contracted coccidiosis.

Methods

In this investigation, 100 one-day-old Cobb broiler chicks without sexes were employed. The chicks were divided into five equal groups, with 20 birds in each. On the 14th day of life, the birds in groups 2, 3, 4, and 5 received an oral inoculation with 1 × 105 sporulated oocysts of Eimeria tenella (E. tenella) (field isolate). The first group (Gp), which consists of 20 healthy broilers, served as a negative control. Gp (2) contains experimentally infected broilers and nontreated (served as a positive control). Gp (3) contains experimentally infected broilers treated with toltrazuril (1 ml/l drinking water) for two consecutive days. Gp (4) contains experimentally infected broilers treated with neem leaf extract 4% (50 ml/l drinking water) for 5 successive days, and Gp (5) contains experimentally infected broilers treated with toltrazuril (1 ml/l drinking water) and a half dose of neem leaves extract 4% (25 ml/l drinking water) for 5 successive days. For the purpose of estimating body weight growth and feed conversion ratio, each broiler was weighed separately at the start of the trial and again on the 1st and 10th day after treatment. In addition to obtaining intestinal samples for immunohistochemistry, blood samples were also obtained for immunological examination.

Results

As compared to the negative control group, the experimentally infested broilers with E. tenella showed significant decreases in serum nitric oxide, lysosome, phagocytic percent, and phagocytic index, along with significant increases in white blood cells (WBCs), lymphocyte, heterophilis, eosinophilis, basophilis, monocyte, serum total protein, γ globulin, fibrinogen, and haptoglobin. When compared to the control positive group, experimentally infested broilers treated with either neem or toltrazuril alone or in combination demonstrated significant increases in serum total protein, nitric oxide, lysozyme, phagocytic percent, and phagocytic index, but significant decreases in WBCs, lymphocytes, heterophile, eosinophile, basophile, and monocyte. The intestinal peroxidase stain of broilers infected with E. tenella exhibited a significant positive expression for CD4, but the infected broilers treated with toltrazuril and half a dosage of neem displayed a negative expression for CD4, identical to the negative control.

Conclusion

The broiler chickens infested with E. tenella may have a variety of negative impacts on their immune systems and immunohistopathological findings. Nonetheless, toltrazuril and neem extract, either separately or in combination, function as anticoccidial medications that may enhance the broiler chicks' immune state.

Few and far between: clinical management of rare extranodal subtypes of mature T-cell and NK-cell lymphomas

While all peripheral T-cell lymphomas are uncommon, certain subtypes are truly rare, with less than a few hundred cases per year in the USA. There are often no dedicated clinical trials in these rare subtypes, and data are generally limited to case reports and retrospective case series. Therefore, clinical management is often based on this limited literature and extrapolation of data from the more common, nodal T-cell lymphomas in conjunction with personal experience. Nevertheless, thanks to tremendous pre-clinical efforts to understand these rare diseases, an increasing appreciation of the biological changes that underlie these entities is forming. In this review, we attempt to summarize the relevant literature regarding the initial management of certain rare subtypes, specifically subcutaneous panniculitis-like T-cell lymphoma, hepatosplenic T-cell lymphoma, intestinal T-cell lymphomas, and extranodal NK/T-cell lymphoma. While unequivocally established approaches in these diseases do not exist, we make cautious efforts to provide our approaches to clinical management when possible.

Metronomic chemotherapy for indolent T-cell lymphoproliferative disorder of the gastrointestinal tract

The present study proposes metronomic chemotherapy (CPT), including prednisolone, cyclophosphamide, and thalidomide, as a treatment for patients with severe symptomatic indolent T‐cell lymphoproliferative disorder of the gastrointestinal tract. The encouraging efficacy and excellent safety profile of CPT suggest the clinical potential of this combination.

Extranodal T- and NK-cell lymphomas

Non-cutaneous extranodal NK/T cell lymphoproliferations constitute a heterogenous group of rare neoplasms, occurring primarily in the gastro-intestinal tract, nasal area, spleen, and liver. Their nomenclature refers to their usual clinical presentation and predilection for specific anatomic sites-i.e. extranodal NK/T-cell lymphoma, nasal-type, hepatosplenic T-cell lymphoma, primary intestinal T-cell lymphomas, indolent lymphoproliferative disorders of the gastrointestinal tract, and breast implant-associated anaplastic large cell lymphoma. Extranodal tissues may also be involved by T-cell leukemias, or other entities usually presenting as nodal diseases. Primary extranodal entities range from indolent to highly aggressive diseases. Here, we will review the clinicopathologic features of the pertinent entities including the recent advances in their molecular and genetic characterization, with an emphasis on the changes introduced in the 2022 International Consensus Classification of lymphoid neoplasms, and highlight the diagnostic criteria helpful to sort out the distinction with potential mimickers.

Indolent T-cell lymphoproliferative disorder of gastrointestinal tract with unusual clinical courses: report of 6 cases and literature review

Indolent T-cell lymphoproliferative disorder of the gastrointestinal tract (iTLPD-GI) is a rare neoplasm usually having an indolent clinical course and easily misdiagnosed as inflammatory bowel disease or other T-cell lymphomas. A subset of the disorders that progressed to overt peripheral T-cell lymphoma have been reported, and the etiology and pathogenesis are poorly understood. The current study retrospectively examined the pathological, molecular, and clinical features of 6 cases of iTLPD-GI. Hematoxylin and eosin staining, immunohistochemistry, in situ hybridization, T-cell receptor gene rearrangement, and next-generation sequencing (NGS) were performed with the diseased tissues. All the 6 patients were immunocompetent Chinese men, who presented with recurrent abdominal pain and diarrhea for 4 to 13 years. Histologically, the intestinal tissue was expanded by lymphoid infiltration, composed of small-to-medium-sized lymphocytes with gland intact. The neoplastic cells were CD4 - /CD8 + with expression of TIA1 and variable granzyme B in five cases, and the other one was CD4 + /CD8 - . Two of the 5 patients progressed to more aggressive T-cell lymphoma and died of disease with complications. NGS identified TET2 and DDX3X mutations in patient 1, and BIRC6 and REV3L mutations in patient 2. Literature review indicated that iTLPD-GI with CD4 - /CD8 + immunophenotype was more commonly reported in Chinese cases. Our limited data indicated CD4-/CD8 + iTLPD-GI have similar potential to progress to more aggressive T-cell lymphoma as that of CD4 + /CD8 - , and gradually increased expression of granzyme B and Ki-67 may be early signs of the disease progression. Gain of novel gene mutations may be indicators of the pathogenesis.

CD8-positive indolent T-Cell lymphoproliferative disorder of the gastrointestinal tract: A case report and review of literature

BACKGROUND

Indolent T-cell lymphoproliferative disorder of the gastrointestinal tract (ITLPD-GI), a primary tumor forming in the gastrointestinal (GI) tract, represents a rarely diagnosed clonal T-cell disease with a protracted clinical course.

CASE SUMMARY

This report presented a 45-year-old male patient with a 6-year history of anal fistula and a more than 10-year history of recurrent diarrhea who was not correctly diagnosed until the occurrence of complications such as intestinal perforation. Postsurgical histopathological analysis, combined with hematoxylin-eosin staining, immunohistochemistry and TCRβ/γ clonal gene rearrangement test, confirmed the diagnosis of CD8+ ITLPD-GI.

CONCLUSION

Individuals with this scarce lymphoma frequently show non-specific symptoms that are hard to recognize. So far, indolent CD8+ ITLPD-GI has not been comprehensively examined. The current mini-review focused on evaluating indolent CD8+ ITLPD-GI cases based on existing literature and discussing future directions for improved differential diagnosis, detection of genetic and epigenetic alterations, and therapeutic target identification.

Cellular Origins and Pathogenesis of Gastrointestinal NK- and T-Cell Lymphoproliferative Disorders

The intestinal immune system, which must ensure appropriate immune responses to both pathogens and commensal microflora, comprises innate lymphoid cells and various T-cell subsets, including intra-epithelial lymphocytes (IELs). An example of innate lymphoid cells is natural killer cells, which may be classified into tissue-resident, CD56bright NK-cells that serve a regulatory function and more mature, circulating CD56dim NK-cells with effector cytolytic properties. CD56bright NK-cells in the gastrointestinal tract give rise to indolent NK-cell enteropathy and lymphomatoid gastropathy, as well as the aggressive extranodal NK/T cell lymphoma, the latter following activation by EBV infection and neoplastic transformation. Conventional CD4+ TCRαβ+ and CD8αβ+ TCRαβ+ T-cells are located in the lamina propria and the intraepithelial compartment of intestinal mucosa as type 'a' IELs. They are the putative cells of origin for CD4+ and CD8+ indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and intestinal T-cell lymphoma, NOS. In addition to such conventional T-cells, there are non-conventional T-cells in the intra-epithelial compartment that express CD8αα and innate lymphoid cells that lack TCRs. The central feature of type 'b' IELs is the expression of CD8αα homodimers, seen in monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), which primarily arises from both CD8αα+ TCRαβ+ and CD8αα+ TCRγδ+ IELs. EATL is the other epitheliotropic T-cell lymphoma in the GI tract, a subset of which arises from the expansion and reprograming of intracytoplasmic CD3+ innate lymphoid cells, driven by IL15 and mutations of the JAK-STAT pathway.

Primary Gastrointestinal T-Cell Lymphoma and Indolent Lymphoproliferative Disorders: Practical Diagnostic and Treatment Approaches

Simple Summary

It is challenging for pathologists to diagnose primary gastrointestinal T-cell neoplasms. Besides the rarity of the diseases, the small biopsy material makes it more difficult to differentiate between non-neoplastic inflammation and secondary involvement of extra gastrointestinal lymphoma. Since this group of diseases ranges from aggressive ones with a very poor prognosis to indolent ones that require caution to avoid overtreatment, the impact of the diagnosis on the patient is enormous. Although early treatment of aggressive lymphoma is essential, the treatment strategy is not well established, which is a problem for clinicians. This review provides a cross-sectional comparison of histological findings. Unlike previous reviews, we summarized up-to-date clinically relevant information including the treatment strategies as well as practical differential diagnosis based on thorough literature review.

Abstract

Primary gastrointestinal (GI) T-cell neoplasms are extremely rare heterogeneous disease entities with distinct clinicopathologic features. Given the different prognoses of various disease subtypes, clinicians and pathologists must be aware of the key characteristics of these neoplasms, despite their rarity. The two most common aggressive primary GI T-cell lymphomas are enteropathy-associated T-cell lymphoma and monomorphic epitheliotropic intestinal T-cell lymphoma. In addition, extranodal natural killer (NK)/T-cell lymphoma of the nasal type and anaplastic large cell lymphoma may also occur in the GI tract or involve it secondarily. In the revised 4th World Health Organization classification, indolent T-cell lymphoproliferative disorder of the GI tract has been incorporated as a provisional entity. In this review, we summarize up-to-date clinicopathological features of these disease entities, including the molecular characteristics of primary GI T-cell lymphomas and indolent lymphoproliferative disorders. We focus on the latest treatment approaches, which have not been summarized in existing reviews. Further, we provide a comprehensive review of available literature to address the following questions: How can pathologists discriminate subtypes with different clinical prognoses? How can primary GI neoplasms be distinguished from secondary involvement? How can these neoplasms be distinguished from non-specific inflammatory changes at an early stage?

Indolent T-Cell Lymphoproliferative Disorders of the Gastrointestinal Tract (iTLPD-GI): A Review

Simple Summary

This review aims to better define the clinical, pathological, and molecular features of the novel lymphoproliferative disease termed “indolent T-cell lymphoproliferative disorder of the gastro-intestinal tract (iTLPD-GI)”, to discuss potential pitfalls in differentiating this entity from other neoplastic and non-neoplastic disorders arising at the same site, and to point out a biomarker-based approach to the diagnosis.

Abstract

iTLPD-GI is a low-grade clonal T-cell lymphoproliferative disease arising in GI organs. It is an uncommon disease, and only recently has it been enlisted as a distinct provisional entity in the current WHO Classification. Data from the literature disclose high heterogeneity in terms of pathological and molecular features; on the other hand, establishing an accurate diagnosis of iTLPD-GI is of pivotal importance, since treatment options are different from that of other, more frequent lymphomas that arise in the gastrointestinal tract. In this review, we aimed to better define this novel entity, and to identify useful diagnostic biomarkers; moreover, we provide a biomarker-based approach to the diagnosis and describe the most common issues in differentiating iTLPD-GI from other neoplastic and non-neoplastic disorders.

Diagnostic approach to T- and NK-cell lymphoproliferative disorders in the gastrointestinal tract

Most gastrointestinal NK and T cell lymphomas are aggressive in behavior, although in recent years a subset of indolent lymphoproliferative disorders have been described, which must be distinguished from their more malignant mimics. Intestinal T-cell lymphomas may arise from intra-epithelial lymphocytes and display epitheliotropism, such as enteropathy-associated T-cell lymphoma and monomorphic epitheliotropic intestinal T-cell lymphoma. They are both aggressive in behavior but differ in their clinic-pathological features. On the other hand, intra-epithelial lymphocytes are not prominent in intestinal T-cell lymphoma, NOS, which is a diagnosis of exclusion and probably represents a heterogeneous group of entities. Indolent lymphoproliferative disorders of NK- and T-cells of both CD8 and CD4 subsets share a chronic, recurring clinical course but display differences from each other. CD8+ T-cell lymphoproliferative disorder of GI tract has a low proliferative fraction and does not progress nor undergo large cell transformation. Whilst NK-cell enteropathy runs an indolent clinical course, it may display a high proliferation fraction. On the other hand, CD4+ indolent T-cell lymphoproliferative disorder displays variable proliferation rates and may progress or transform after a number of years. In Asia and South America, it is not uncommon to see involvement of the gastrointestinal tract by EBV-associated extranodal NK/T cell lymphoma, nasal type, which must be distinguished from NK cell enteropathy and EBV-associated mucocutaneous ulcers.

Immune-mediated enteropathies: From bench to bedside

Immune-mediated enteropathies are caused by excessive reactions of the intestinal immune system towards non-pathogenic molecules. Enteropathy leads to malabsorption-related symptoms and include (severe) chronic diarrhea, weight loss and vitamin deficiencies. Parenteral feeding and immunosuppressive therapy are needed in severe cases. Celiac disease has long been recognized as the most common immune-mediated enteropathy in adults, but the spectrum of immune-mediated enteropathies has been expanding. Histological and clinical features are sometimes shared among these enteropathies, and therefore it may be challenging to differentiate between them. Here, we provide an overview of immune-mediated enteropathies focused on clinical presentation, establishing diagnosis, immunopathogenesis, and treatment options.

Recent advances upper gastrointestinal lymphomas: molecular updates and diagnostic implications

Approximately one-third of extranodal non-Hodgkin lymphomas involve the gastrointestinal (GI) tract, with the vast majority being diagnosed in the stomach, duodenum, or proximal small intestine. A few entities, especially diffuse large B-cell lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, represent the majority of cases. In addition, there are diseases specific to or characteristic of the GI tract, and any type of systemic lymphoma can present in or disseminate to these organs. The recent advances in the genetic and molecular characterisation of lymphoid neoplasms have translated into notable changes in the classification of primary GI T-cell neoplasms and the recommended diagnostic approach to aggressive B-cell tumours. In many instances, diagnoses rely on morphology and immunophenotype, but there is an increasing need to incorporate molecular genetic markers. Moreover, it is also important to take into consideration the endoscopic and clinical presentations. This review gives an update on the most recent developments in the pathology and molecular pathology of upper GI lymphoproliferative diseases.

Intestinal NK/T cell lymphoma: A case report

BACKGROUND

The incidence of intestinal NK/T cell lymphoma (NKTCL) is extremely low, and the clinical symptoms are atypical, which makes it difficult to distinguish this disorder from Crohn's disease (CD), T lymphocyte proliferative disease, and other immune disorders. The misdiagnosis rate is high, and the patient's prognosis is poor.

CASE SUMMARY

In this case, the patient had repeated high fever, colonoscopy revealed multiple ulcers, and the initial diagnosis was CD. The patient’s condition did not improve after treatment with hormones and infliximab, and she eventually died. Positron emission tomographic-computed tomographic and B-ultrasound were performed in our hospital and showed that multiple lymph nodes were enlarged. Immunohistochemi-stry showed that CD3 and Epstein-Barr virus encoded RNA expression was positive. Colonoscopy, tissue biopsy, and histopathology showed intestinal focal mucosal infiltration of heterotypic lymphocytes with an abnormal immune phenotype. On the basis of the patient’s medical history, auxiliary examination, and pathological findings, digestive physicians and pathologists gave the diagnosis of NKTCL.

CONCLUSION

Clinicians need to improve their comprehensive knowledge of NKTCL, and combination of clinical symptoms, histological characteristics, as well as colonoscopy biopsies should be considered to improve the diagnosis and thereby reduce misdiagnosis.

T- and NK-cell lymphoproliferative disorders of the gastrointestinal tract: review and update

T- and NK-cell lymphoproliferative disorders of the gastrointestinal (GI) tract are uncommon, but are important to recognise as there may be morphological and immunophenotypic overlap between lymphoid lesions with vastly different clinical outcomes. Recent data have led to the reclassification of some lymphomas and inclusion of new entities in the 2016 revision of World Health Organization (WHO) classification of lymphoid neoplasms. It has become clear that enteropathy associated T-cell lymphoma (EATL), formerly thought to be composed of two subtypes known as type I and type II, are distinct entities. Type I EATL is now simply classified as EATL; it is strongly associated with coeliac disease and occurs mainly in Western populations. Type II EATL has been renamed monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL); it shows no definite association with coeliac disease and occurs worldwide with a predominance in Asian populations. There is also a group of aggressive intestinal T-cell lymphomas which do not meet criteria for EATL, MEITL, extranodal NK/T-cell lymphoma of nasal type or anaplastic large cell lymphoma. These neoplasms are now designated intestinal T-cell lymphoma, not otherwise specified. Indolent T-cell lymphoproliferative disorder of the GI tract has been included as a provisional entity in the most recent WHO classification. It is a clonal T-cell lymphoproliferative disorder (CD4+ or CD8+) with an indolent clinical course. Finally, benign NK-cell proliferations of the GI tract, variably designated 'NK-cell enteropathy' and 'lymphomatoid gastropathy' have also been recognised in the last two decades but have not been included in the WHO classification as their neoplastic nature is not established. This review covers the aforementioned lymphoid proliferations, emphasising their salient clinicopathological features and genetic abnormalities. It also provides practical insights into resolving difficult differential diagnoses in daily surgical pathology practice.

Genetic and phenotypic characterization of indolent T-cell lymphoproliferative disorders of the gastrointestinal tract

Indolent T-cell lymphoproliferative disorders of the gastrointestinal tract are rare clonal T-cell diseases that more commonly occur in the intestines and have a protracted clinical course. Different immunophenotypic subsets have been described, but the molecular pathogenesis and cell of origin of these lymphocytic proliferations is poorly understood. Hence, we performed targeted next-generation sequencing and comprehensive immunophenotypic analysis of ten indolent T-cell lymphoproliferative disorders of the gastrointestinal tract, which comprised CD4⁺ (n=4), CD8⁺ (n=4), CD4⁺/CD8⁺ (n=1) and CD4^-/CD8^- (n=1) cases. Genetic alterations, including recurrent mutations and novel rearrangements, were identified in 8/10 (80%) of these lymphoproliferative disorders. The CD4⁺, CD4⁺/CD8⁺, and CD4^-/CD8^- cases harbored frequent alterations of JAK-STAT pathway genes (5/6, 82%); STAT3 mutations (n=3), SOCS1 deletion (n=1) and STAT3-JAK2 rearrangement (n=1), and 4/6 (67%) had concomitant mutations in epigenetic modifier genes (TET2, DNMT3A, KMT2D). Conversely, 2/4 (50%) of the CD8⁺ cases exhibited structural alterations involving the 3' untranslated region of the IL2 gene. Longitudinal genetic analysis revealed stable mutational profiles in 4/5 (80%) cases and acquisition of mutations in one case was a harbinger of disease transformation. The CD4⁺ and CD4⁺/CD8⁺ lymphoproliferative disorders displayed heterogeneous Th1 (T-bet⁺), Th2 (GATA3⁺) or hybrid Th1/Th2 (T-bet⁺/GATA3⁺) profiles, while the majority of CD8⁺ disorders and the CD4^-/CD8^- disease showed a type-2 polarized (GATA3⁺) effector T-cell (Tc2) phenotype. Additionally, CD103 expression was noted in 2/4 CD8⁺ cases. Our findings provide insights into the pathogenetic bases of indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and confirm the heterogeneous nature of these diseases. Detection of shared and distinct genetic alterations of the JAK-STAT pathway in certain immunophenotypic subsets warrants further mechanistic studies to determine whether therapeutic targeting of this signaling cascade is efficacious for a proportion of patients with these recalcitrant diseases.

NKp46 is a diagnostic biomarker and may be a therapeutic target in gastrointestinal T-cell lymphoproliferative diseases: a CELAC study

OBJECTIVES

Primary GI T-cell lymphoproliferative diseases (T-LPD) are heterogeneous entities, which raise difficult diagnosis and therapeutic challenges. We have recently provided evidences that lymphomas complicating coeliac disease (CD) arise from innate-like lymphocytes, which may carry NK receptors (NKRs).

DESIGN

NKRs expression was compared by flow cytometry in intraepithelial lymphocytes (IEL) from CD, type I or type II refractory CD (RCD). NKp46 was next assessed by immunohistochemistry in paraffin-embedded biopsies from 204 patients with CD, RCDI, RCDII or GI T-cell lymphomas and from a validation cohort of 61 patients. The cytotoxic properties of an anti-NKp46 monoclonal antibody conjugated to pyrrolobenzodiazepine (PBD) was tested ex vivo in human primary tumour cells isolated from fresh duodenal biopsies.

RESULTS

NKp46 (but not CD94, NKG2A, NKG2C, NKG2D) was significantly more expressed by malignant RCDII IEL than by normal IEL in CD and RCDI. In paraffin biopsies, detection of >25 NKp46+ IEL per 100 epithelial cells discriminated RCDII from CD and RCDI. NKp46 was also detected in enteropathy-associated T-cell lymphomas (EATL, 24/29) and in monomorphic epitheliotropic intestinal T-cell lymphomas (MEITL, 4/4) but not in indolent T-LPD (0/15). Treatment with anti-NKp46-PBD could efficiently and selectively kill human NKp46+ primary IEL ex vivo.

CONCLUSION

NKp46 is a novel biomarker useful for diagnosis and therapeutic stratification of GI T-LPD. Strong preclinical rationale identifies anti-NKp46-PBD as a promising therapy for RCDII, EATL and MEITL.

Update on Gastrointestinal Lymphomas

Herein we review the following selection of gastrointestinal lymphomas: monomorphic epitheliotropic intestinal T-cell lymphoma; indolent T-cell lymphoproliferative disorder of the gastrointestinal tract; intestinal T-cell lymphoma, not otherwise specified; duodenal-type follicular lymphoma; and Epstein-Barr virus-positive mucocutaneous ulcer. Definitions reflect the 2016 revision of the World Health Organization classification of lymphoid neoplasms. Clinical, morphologic, and immunophenotypic characteristics of each entity are emphasized.

New/Revised Entities in Gastrointestinal Lymphoproliferative Disorders

The gastrointestinal tract is a common extranodal site of involvement by lymphomas. These may be diagnostically challenging because they can mimic a variety of benign conditions and may be difficult to subclassify when malignant. The classification of gastrointestinal lymphomas is an evolving area with some recent changes. Although some of these entities are rare, they are important to recognize because of the variable clinical presentations, comorbidities, and treatment implications. This article explores new and revised entities in gastrointestinal lymphoproliferative disorders.

Indolent T cell lymphoproliferative disorder with villous atrophy in small intestine diagnosed by single-balloon enteroscopy

Chronic diarrhea is one of the major symptoms in gastroenterology. However, this may be caused by pathologic conditions for which the diagnosis is critical. Villous atrophy, as an endoscopic lesion, accompanied by chronic diarrhea can occasionally be observed in the patients with inflammatory diseases of the gastrointestinal (GI) tract. Herein, we present a case with persistent diarrhea accompanied by intestinal wall thickening without any other significant endoscopic features other than villous atrophy in the jejunum and the ileum, where we diagnosed as an indolent T cell lymphoproliferative disorder (T-LPD) of the GI tract, defined in the 2016–2017 revised World Health Organization classification, via single-balloon enteroscopy (SBE). Interestingly, we found the same lymphocyte infiltration from the distal third portion of the duodenum, where gastroscopy could not reach, via SBE, even though no endoscopic findings were observed such as villous atrophy. Since infiltrating cells in the intestinal tissues were CCR4⁺, mogamulizumab was administered with resulting durable symptomatic remission for more than 2 years. Patients with persistent diarrhea may have serious small intestinal disorder including not only chronic inflammatory diseases but also lymphoid neoplasmic conditions including T-LPD of GI tract.

Indolent T-cell lymphoproliferative disease with synchronous diffuse large B-cell lymphoma: A case report

RATIONALE

Indolent T-cell lymphoproliferative disease (T-LPD) of gastrointestinal tract is a rare recently described disease that seldom progresses. We report a case of T-LPD with synchronous diffuse large B-cell lymphoma (DLBCL) that cause aggravation of disease.

PATIENT CONCERNS

A 46-year-old Chinese male presented with intermittent paraumbilical colic pain, bloating, and occasional diarrhea for 10 years. His condition aggravated with partial bowel obstruction recently. The patient was diagnosed as T-LPD initially based on histological result and T-cell receptor-gamma clonal gene rearrangement test. The patient was followed without chemotherapy. His condition stabilized for 1 year and then deteriorated with small intestine perforation.

DIAGNOSIS

The patient was diagnosed as indolent T-LPD and DLBCL finally.

INTERVENTIONS

The patient had surgery for intestine perforation and received chemotherapy for DLBCL and T-LPD afterward.

OUTCOMES

At 6 months follow-up, the patient continued to have resolution of his symptoms.

LESSONS

Early detection of high-grade transformation of T-LPD or the coexistence of aggressive lymphoma is essential for the patient. DLBCL may coexist in the indolent course of T-LPD. The diagnosis of T-LPD should be made cautiously in case with progressing symptoms such as intestinal obstruction.

An unusual case report of indolent T-cell lymphoproliferative disorder with aberrant CD20 expression involving the gastrointestinal tract and bone marrow

Background

Indolent T-cell proliferative disorder of the GIT is a rare and provisional entity in the revised WHO 2016 classification. The patients usually have prolonged survival with persistent disease even without any treatment.

Case presentation

The 46 years old male patient has been followed up for more than 6 years without chemotherapy. Repeated gastrointestinal biopsies showed expansion of the lamina propria extending to the submucosa by small to medium sized lymphocytes with minimal cytologic atypia. The lymphoid cells were positive for CD3, CD43, TIA-1, CD2, CD7 and the B-cell marker CD20; but negative for CD4, CD8, PAX5, CD56, cyclinD1, granzyme (GraB) and Epstein Barr virus-encoded RNA (EBER). Ki-67(MIB1) index was less than 10%. Molecular tests demonstrated a clonal rearrangement for T-cell receptor γ (TCR γ) gene but immunoglobulin chain (IgH, IgK, IgL) gene remained germline. Recognition of possible aberrant CD20 expression in indolent T-cell LPD is important to avoid potential diagnostic pitfall and improper treatment.

Conclusions

We present an unusual case of indolent T-cell lymphoproliferative disorder with aberrant CD20 expression, Recognition of this unusual immunophenotype of indolent T-cell LPD of GI helps to eschew misdiagnosis of B-cell and other high grade lymphomas and inappropriate aggressive treatment.

Feline low-grade alimentary lymphoma: an emerging entity and a potential animal model for human disease

BACKGROUND

Low-grade alimentary lymphoma (LGAL) is characterised by the infiltration of neoplastic T-lymphocytes, typically in the small intestine. The incidence of LGAL has increased over the last ten years and it is now the most frequent digestive neoplasia in cats and comprises 60 to 75% of gastrointestinal lymphoma cases. Given that LGAL shares common clinical, paraclinical and ultrasonographic features with inflammatory bowel diseases, establishing a diagnosis is challenging. A review was designed to summarise current knowledge of the pathogenesis, diagnosis, prognosis and treatment of feline LGAL. Electronic searches of PubMed and Science Direct were carried out without date or language restrictions.

RESULTS

A total of 176 peer-reviewed documents were identified and most of which were published in the last twenty years. 130 studies were found from the veterinary literature and 46 from the human medicine literature. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. The pathophysiology of feline LGAL still needs to be elucidated, not least the putative roles of infectious agents, environmental factors as well as genetic events. The most common therapeutic strategy is combination treatment with prednisolone and chlorambucil, and prolonged remission can often be achieved. Developments in immunohistochemical analysis and clonality testing have improved the confidence of clinicians in obtaining a correct diagnosis between LGAL and IBD. The condition shares similarities with some diseases in humans, especially human indolent T-cell lymphoproliferative disorder of the gastrointestinal tract.

CONCLUSIONS

The pathophysiology of feline LGAL still needs to be elucidated and prospective studies as well as standardisation of therapeutic strategies are needed. A combination of conventional histopathology and immunohistochemistry remains the current gold-standard test, but clinicians should be cautious about reclassifying cats previously diagnosed with IBD to lymphoma on the basis of clonality testing. Importantly, feline LGAL could be considered to be a potential animal model for indolent digestive T-cell lymphoproliferative disorder, a rare condition in human medicine.

A Single-Tube, EuroClonality-Inspired, TRG Clonality Multiplex PCR Aids Management of Patients with Enteropathic Diseases, including from Formaldehyde-Fixed, Paraffin-Embedded Tissues

Celiac disease is a chronic inflammation of the small intestine with villous atrophy that can become refractory to a gluten-free diet. Two categories of refractory celiac disease can be distinguished by the phenotype of intraepithelial lymphocytes and the status of TRG genes. Their distinction is important because 30% to 50% of type II but only 0% to 14% of type I evolve to an aggressive enteropathy-associated T-cell lymphoma and therefore require intensive treatment. Currently, differential diagnosis integrates immunohistochemistry, immunophenotyping, and TRG clonality analyses, but each has limitations. A single-tube multiplex TRG PCR (ECN) was prospectively compared to an in-house two-tube TRG PCR (N2T) in 73 samples, including 67 cryopreserved intestine tissues. Thirteen formalin-fixed, paraffin-embedded (FFPE) samples were also analyzed retrospectively. The ECN PCR had comparable efficiency to detect major clonal rearrangements in highly infiltrated tissues from T-cell lymphoproliferative disorders and type II refractory celiac disease and to detect the persistence of minor clones in type II refractory celiac disease follow-up samples. The ECN PCR abolished the risk of amplification of false-positive weak clonal rearrangements in cryopreserved specimens and allowed improved detection of clonal rearrangements in DNA from FFPE samples. The ECN PCR allows robust assessment of cryopreserved and FFPE digestive tissues at diagnosis and follow-up of enteropathies with villous atrophy, thus guiding therapeutic management.

Disease Progression in a Patient With Indolent T-Cell Lymphoproliferative Disease of the Gastrointestinal Tract

Indolent T-cell lymphoproliferative disorder (T-LPD) of the gastrointestinal (GI) tract is a new provisional entity in the 2016 revision of the World Health Organization classification. The disease has an indolent course and progression to aggressive T-cell lymphoma has rarely been reported. We describe a case of a 37-year-old male with indolent T-LPD of the GI tract who 3 years later developed aggressive T-cell lymphoma and died of progressive disease. An infiltrate of indolent T-LPD in the GI tract and aggressive lymphoma diagnosed from the liver biopsy had similar immunophenotype, but cellular infiltrate in the liver showed more atypia compared with the GI biopsies of indolent T-LPD. Moreover, T-cell gene rearrangement studies showed an identical clonal rearrangement in indolent T-LPD and aggressive lymphoma. Patients with indolent T-LPD of the GI tract need a long-term follow-up, as some of them may develop more aggressive lymphoma.

Gastrointestinal lymphomas: French Intergroup clinical practice recommendations for diagnosis, treatment and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, SFH)

INTRODUCTION

This document is a summary of the French Intergroup guidelines on the management of gastro-intestinal lymphomas, available on the web-site of the French Society of Gastroenterology, SNFGE (www.tncd.org), updated in September 2017.

METHODS

This collaborative work was realised under the auspices of several French medical societies and involved clinicians with specific expertise in the field of gastrointestinal lymphomas, including gastroenterologists, haematologists, pathologists, and radiation oncologist, representing the major French or European clinical trial groups. It summarises their consensus on the management of gastrointestinal lymphomas, based on the recent literature data, previous published guidelines and the expert opinions.

RESULTS

The clinical management, and especially the therapeutic strategies of the gastro-intestinal lymphomas are specific to their histological subtypes and to their locations in the digestive tract, with the particularity of gastric MALT lymphomas which are the most frequent and usually related to gastritis induced by Helicobacter pylori.

CONCLUSION

Lymphomas are much less common than epithelial tumours of gastro-intestinal digestive tract. Their different histological subtypes determine their management and prognosis. Each individual case should be discussed within the expert multidisciplinary team.

Indolent T- and NK-cell lymphoproliferative disorders of the gastrointestinal tract: a review and update

Primary gastrointestinal (GI) T- and NK-cell lymphomas are usually aggressive neoplasms associated with high morbidity and mortality. Over the past two decades, however, cases of primary GI lymphoproliferative disorders (LPDs) or lymphomas of T- or NK-cell derivation with indolent behavior have been reported. These LPDs are rare and they can be challenging to diagnose as they share clinical and pathological features with both, inflammatory disorders and aggressive T- and NK-cell lymphomas. Primary, indolent clonal T-cell proliferations of the GI tract, which can be CD4+, CD8+ or CD4- CD8-, have been included as a provisional entity in the newly revised World Health Organization (WHO) classification of lymphoid neoplasms and designated 'indolent T-cell LPD of the GI tract'. It is currently unclear whether the indolent NK-cell LPDs represent reactive or neoplastic proliferations. In this review, we describe the clinical, morphologic, immunophenotypic and genetic features of indolent GI T- and NK-cell LPDs and provide guidance in differentiating them from other inflammatory and neoplastic diseases. We believe that greater awareness of these LPDs amongst physicians and the research community will lead to timely and accurate diagnoses, stimulate investigations into the pathogenetic mechanisms underlying different entities thereby enhancing our understanding of disease biology and enable the development of effective therapeutic regimens. Copyright © 2016 John Wiley & Sons, Ltd.

Early lymphoid lesions: conceptual, diagnostic and clinical challenges

There are no "benign lymphomas", a fact due to the nature of lymphoid cells to circulate and home as part of their normal function. Thus, benign clonal expansions of lymphocytes are only rarely recognized when localized. Recent studies have identified a number of lymphoid proliferations that lie at the interface between benign and malignant. Some of these are clonal proliferations that carry many of the molecular hallmarks of their malignant counterparts, such as BCL2/IGH and CCND1/IGH translocations associated with the in situ forms of follicular lymphoma and mantle cell lymphoma, respectively. There are other clonal B-cell proliferations with low risk of progression; these include the pediatric variants of follicular lymphoma and marginal zone lymphoma. Historically, early or incipient forms of T/NK-cell neoplasia also have been identified, such as lymphomatoid papulosis and refractory celiac disease. More recently an indolent form of T-cell lymphoproliferative disease affecting the gastrointestinal tract has been described. Usually, CD8(+), the clonal cells are confined to the mucosa. The clinical course is chronic, but non-progressive. NK-cell enteropathy is a clinically similar condition, composed of cytologically atypical NK-cells that may involve the stomach, small bowel or colon. Breast implant-associated anaplastic large cell lymphoma is a cytologically alarming lesion that is self-limited if confined to the seroma cavity. Atypical lymphoid proliferations that lie at the border of benign and malignant can serve as instructive models of lymphomagenesis. It is also critical that they be correctly diagnosed to avoid unnecessary and potentially harmful therapy.

Profile of CD103 expression in T-cell neoplasms: immunoreactivity is not restricted to enteropathy-associated T-cell lymphoma

Intestinal intraepithelial T lymphocytes express the α E subunit of integrin αEβ7, which is detected by antibodies to CD103. Accordingly, within T-cell neoplasms, CD103 reactivity has most frequently been reported in enteropathy-associated T-cell lymphomas, which are postulated to arise from intestinal intraepithelial T lymphocytes. However, prior studies of CD103 expression in T-cell neoplasms have been limited by the requirement for fresh or frozen tissue, given the historic lack of an antibody to CD103 for use in paraffin-embedded sections. Thus, a thorough assessment of CD103 expression in a broad spectrum of T-cell neoplasms as categorized by the current classification system has not yet been performed. This study uses a newly described antibody to define the profile of CD103 immunoreactivity in paraffin sections of a wide variety of T-cell neoplasms (184 cases). Overall, 22 T-cell neoplasms (12%) were CD103 positive, including 7 of 15 gastrointestinal lymphomas (3.8% of total cases; 46% of gastrointestinal cases). In intestinal cases, CD103 positivity did not correlate with morphology, presence or absence of enteropathy, or immunohistochemical profile. A history of celiac disease was not documented in any case. Frequent but inconsistent reactivity was also noted for adult T-cell leukemia/lymphoma with 4 of 10 cases (40%) positive. In the remaining T-cell neoplasms representing most entities within the current World Health Organization classification, CD103 reactivity was sporadically observed in 11 of 159 cases (6.9%). CD103 positivity is an unusual feature in T-cell neoplasms and tends to occur in gastrointestinal lymphomas and adult T-cell leukemia/lymphoma but is not a consistent characteristic of these neoplasms.

Cytotoxic T-cell and NK-cell lymphomas: current questions and controversies

The cytotoxic T-cell and natural killer (NK)-cell lymphomas and related disorders are important but relatively rare lymphoid neoplasms that frequently are a challenge for practicing pathologists. This selective review, based on a meeting of the International Lymphoma Study Group, briefly reviews T-cell and NK-cell development and addresses questions related to the importance of precise cell lineage (αβ-type T cell, γδ T cell, or NK cell), the implications of Epstein-Barr virus infection, the significance of anatomic location including nodal disease, and the question of further categorization of enteropathy-associated T-cell lymphomas. Finally, developments subsequent to the 2008 World Health Organization Classification, including the recognition of indolent NK-cell and T-cell disorders of the gastrointestinal tract are presented.

Olmesartan-associated enteropathy: results of a national survey

BACKGROUND

Recently, a new enteropathy has been described: olmesartan-associated enteropathy. However, the association has been questioned: a phase 3 trial and a cohort study found no association between gastrointestinal events and olmesartan.

AIM

To collect French cases of sartan-associated enteropathy to describe further this entity, confirm or refute causality, and determine if the association exists with other sartans.

METHODS

French gastroenterologists were invited to report cases of sartan-associated enteropathy and collect clinical, biological and histological data. Patients with diarrhoea and histological duodenal abnormalities were included.

RESULTS

Thirty-six patients with olmesartan-associated enteropathy were reported, including 32 with villous atrophy and four without. There was only one patient with irbesartan-associated enteropathy. None of the patients died. Patients with villous atrophy had diarrhoea, vomiting, renal failure, hypokalaemia, body weight loss and hypoalbuminaemia. Thirty-one patients were hospitalised; four required intensive care. Anti-transglutaminase and anti-enterocyte antibodies were negative; anti-nuclear antibodies were positive (9/11). Endoscopic duodenal biopsies showed villous atrophy (32/32) and polyclonal intra-epithelial CD3+CD8+ lymphocytosis (11/11). Exactly, 14/15 patients responded to steroids and/or immunosuppressants, prescribed because of suspected autoimmune enteropathy. Ten olmesartan interruptions were followed by reintroductions before steroids or immunosuppressants. Interruptions were followed by remissions (9/10), but reintroductions were followed by relapses (9/9). Twenty-nine patients were in remission since olmesartan interruption, including 26 without immunosuppressants. Patients with normal villi had similar clinical characteristics, but mild histological abnormalities (intra-epithelial lymphocytosis and lamina propria lymphocytic infiltration).

CONCLUSIONS

Olmesartan causes a severe and immune-mediated enteropathy, with or without villous atrophy. Enteropathy associated with other sartans seems to be very rare.

Small intestinal CD4+ T-cell lymphoma is a heterogenous entity with common pathology features

BACKGROUND & AIMS

Little is known about intestinal CD4+ T-cell lymphoma; this rare malignancy is misdiagnosed frequently. We evaluated diagnostic criteria and factors that might affect its development and outcome.

METHODS

In a retrospective analysis, we analyzed medical records and intestinal specimens from 10 patients diagnosed with intestinal CD4+ T-cell lymphoma among 115 consecutive patients examined for severe enteropathy with villous atrophy. Samples were analyzed by histology, flow cytometry, and comparative genomic hybridization.

RESULTS

Small-intestine epithelial and lamina propria tissues from patients who presented with chronic diarrhea and malnutrition had variable levels of infiltration of CD3+ CD4+ T cells. Flow cytometry showed a high frequency of CD4+ intraepithelial cells, which frequently expressed a specific Vβ chain. T-cell receptor β clonality was confirmed by DNA sequencing. Two patients had HLA and serology results compatible with celiac disease and autoimmune enteropathy, respectively. Two patients were found to have antibodies against human T-cell leukemia virus and 2 patients had signs of a recent infection with the herpes viruses. Comparative genomic hybridization analyses showed heterogeneous chromosomal abnormalities. Symptoms were reduced in patients treated with steroids (n = 5), but not in patients given purine analogues or chemotherapy. Antibodies against CD52 produced clinical and histologic responses in 2 of 2 patients, whereas severe adverse effects developed in 1 patient. At the latest follow-up evaluation, all patients were alive.

CONCLUSIONS

There is much heterogeneity in the onset and genetic features of intestinal CD4+ T-cell lymphomas, despite their common presentation as indolent lymphoproliferations of the intestinal mucosa. Patients should be treated with steroids, and possibly antibodies against CD52 (for the most aggressive forms of this disorder).

Disease severity in familial cases of IBD

BACKGROUND

Phenotypic traits of familial IBD relative to sporadic cases are controversial, probably related to limited statistical power of published evidence.

AIM

To know if there are phenotype differences between familial and sporadic IBD, evaluating the prospective Spanish registry (ENEIDA) with 11,983 cases.

METHODS

5783 patients (48.3%) had ulcerative colitis (UC) and 6200 (51.7%) Crohn's disease (CD). Cases with one or more 1st, 2nd or 3rd degree relatives affected by UC/CD were defined as familial case.

RESULTS

In UC and CD, familial cases compared with sporadic cases had an earlier disease onset (UC: 33 years [IQR 25-44] vs 37 years [IQR 27-49]; p<0.0001); (CD: 27 years [IQR 21-35] vs 29 years [IQR 22-40]; p<0.0001), higher prevalence of extraintestinal immune-related manifestations (EIMs) (UC: 17.2% vs 14%; p=0.04); (CD: 30.1% vs 23.6%; p<0.0001). Familial CD had higher percentage of ileocolic location (42.7% vs 51.8%; p=0.0001), penetrating behavior (21% vs 17.6%; p=0.01) and perianal disease (32% vs 27.1%; p=0.003). Differences are not influenced by degree of consanguinity.

CONCLUSION

When a sufficiently powered cohort is evaluated, familial aggregation in IBD is associated to an earlier disease onset, more EIMs and more severe phenotype in CD. This feature should be taken into account at establishing predictors of disease course.

Indolent T-cell lymphoproliferative disease of the gastrointestinal tract

Primary gastrointestinal (GI) T-cell lymphoma is an infrequent and aggressive disease. However, rare indolent clonal T-cell proliferations in the GI tract have been described. We report 10 cases of GI involvement by an indolent T-cell lymphoproliferative disease, including 6 men and 4 women with a median age of 48 years (range, 15-77 years). Presenting symptoms included abdominal pain, diarrhea, vomiting, food intolerance, and dyspepsia. The lesions involved oral cavity, esophagus, stomach, small intestine, and colon. The infiltrates were dense, but nondestructive, and composed of small, mature-appearing lymphoid cells. Eight cases were CD4(-)/CD8(+), 1 was CD4(+)/CD8(-), and another was CD4(-)/CD8(-). T-cell receptor-γ chain gene rearrangement identified a clonal population in all 10 cases. There was no evidence of STAT3 SH2 domain mutation or activation. Six patients received chemotherapy because of an initial diagnosis of peripheral T-cell lymphoma, with little or no response, whereas the other 4 were followed without therapy. After a median follow-up of 38 months (range, 9-175 months), 9 patients were alive with persistent disease and 1 was free of disease. We propose the name "indolent T-LPD of the GI tract" for these lesions that can easily be mistaken for intestinal peripheral T-cell lymphoma, and lead to aggressive therapy.

Indolent small intestinal CD4+ T-cell lymphoma is a distinct entity with unique biologic and clinical features

Enteropathy-associated T-cell lymphomas (EATL) are rare and generally aggressive types of peripheral T-cell lymphomas. Rare cases of primary, small intestinal CD4+ T-cell lymphomas with indolent behavior have been described, but are not well characterized. We describe morphologic, phenotypic, genomic and clinical features of 3 cases of indolent primary small intestinal CD4+ T-cell lymphomas. All patients presented with diarrhea and weight loss and were diagnosed with celiac disease refractory to a gluten free diet at referring institutions. Small intestinal biopsies showed crypt hyperplasia, villous atrophy and a dense lamina propria infiltrate of small-sized CD4+ T-cells often with CD7 downregulation or loss. Gastric and colonic involvement was also detected (n = 2 each). Persistent, clonal TCRβ gene rearrangement products were detected at multiple sites. SNP array analysis showed relative genomic stability, early in disease course, and non-recurrent genetic abnormalities, but complex changes were seen at disease transformation (n = 1). Two patients are alive with persistent disease (4.6 and 2.5 years post-diagnosis), despite immunomodulatory therapy; one died due to bowel perforation related to large cell transformation 11 years post-diagnosis. Unique pathobiologic features warrant designation of indolent small intestinal CD4+ T-cell lymphoma as a distinct entity, greater awareness of which would avoid misdiagnosis as EATL or an inflammatory disorder, especially celiac disease.

Villous atrophy and negative celiac serology: a diagnostic and therapeutic dilemma

OBJECTIVES

Patients with villous atrophy (VA) and negative celiac disease (CD) serologies pose a diagnostic and therapeutic dilemma. When a definitive etiology for VA is not determined, patients are characterized as having unclassified sprue (US), the optimal management of which is unknown.

METHODS

We studied adult patients with VA on biopsy and negative celiac serologies, evaluated at our tertiary referral center over a 10-year period. Testing for HLA DQ2/8 alleles, antienterocyte antibodies, giardia stool antigen, bacterial overgrowth, total serum immunoglobulins, and HIV was noted. Treatment, response, and repeat-biopsy findings were recorded.

RESULTS

The most common diagnoses of the 72 patients were seronegative CD, medication-related villous atrophy, and US. Of those with US, the majority reported symptomatic improvement with immunosuppressive therapy. Some patients initially labeled as unclassified were found to have VA associated with olmesartan use.

CONCLUSIONS

The role of medications in the development of VA and the optimal dose and length of immunosuppression for patients with US should be investigated further.

Refractory celiac disease: from bench to bedside

Refractory celiac disease is defined by the persistence of symptoms of malnutrition and intestinal villous atrophy for more than 6-12 months despite strict gluten-free diet in celiac patients. Diagnosis of this rare condition is made after excluding other causes of chronic small intestinal inflammation and villous atrophy and inadvertent intake of gluten. Over the past 15 years, multidisciplinary approaches have been developed to assess the mechanism of resistance to the diet, and two distinct entities have been delineated. Type II refractory celiac disease (RCD) can be defined as a low-grade intraepithelial lymphoma. RCD II is characterised by a massive accumulation of abnormal IEL that display an aberrant hybrid NK/T cell phenotype, contain clonal T cell rearrangement(s) and can mediate a cytolytic attack of the gut epithelium. This condition has a severe prognosis, largely due to the frequent transformation of RCDII IEL into overt aggressive enteropathy-type-associated T cell lymphoma. In contrast, in type I RCD, intestinal lymphocytes have a normal phenotype, and this generally milder condition remains often difficult to differentiate from uncomplicated CD except for the resistance to gluten-free diet (GFD). Several mechanisms may underlie resistance to gluten. Herein, we review the distinctive characteristics of RCD I and RCD II, the mechanisms underlying the onset of resistance to GFD, the risk of developing high grade lymphoma and possible clues to improve their treatment.

Primary gastrointestinal tract lymphoma: diagnosis and management of common neoplasms

Primary gastrointestinal lymphoma represents the most common location of extranodal lymphoma. With the bulk of disease manifesting within the gastrointestinal tract and contiguous lymph nodes, many of the lymphomas occurring in the peripheral lymph nodes can also present with primary gastrointestinal tract involvement. Molecular biology has recently enabled significant progress in the diagnosis and management of primary gastrointestinal lymphoma. Herein, we will discuss the major lymphomas affecting the bowel and highlight their key morphological, immunophenotypical and molecular diagnostic attributes. Similarly, in keeping with recent therapeutic advances, we will briefly discuss some important treatment considerations. Thus, this review is intended to offer clinicians and pathologists an overview of primary gastrointestinal lymphomas.

An approach to duodenal biopsies

The introduction of endoscopy of the upper digestive tract as a routine diagnostic procedure has increased the number of duodenal biopsy specimens. Consequently, the pathologist is often asked to evaluate them. In this review, a practical approach to the evaluation of a duodenal biopsy specimen is discussed. An overview of the handling of specimens is given and the normal histology and commonly encountered diseases are discussed. Finally, a description of commonly seen infections is provided, together with an algorithmic approach for diagnosis.

Clinical and pathological features of 14 non-Hodgkin's lymphomas associated with coeliac disease

BACKGROUND

It is well established that enteropathy associated T-cell lymphoma is associated with malabsorption which is due to gluten sensitivity (coeliac disease). Our study was performed to define the clinical features, histological subtypes, response to treatment, and outcome of the association of coeliac disease and T-cell lymphoma.

PATIENTS AND METHODS

A retrospective study was performed in the UCL Group of Hematology to collect data on patients with a diagnosis of non-Hodgkin's lymphoma and coeliac disease. Fifteen cases were observed between 1985 and 1999. Case records for all but one patient were available and the pathological specimens of 14 patients were reviewed by two pathologists.

RESULTS

Six previously diagnosed coeliac patients developed lymphoma; interval between coeliac symptoms and onset of the lymphoma ranged from 2 to 48 years (median 16 years). Five patients had coeliac disease and non-Hodgkin's lymphoma diagnosed concomitantly or less than 6 months before the symptoms leading to the diagnosis of lymphoma. Three patients had the diagnosis of coeliac disease after lymphoma diagnosis (1, 8 and 10 years later respectively). Ten non-Hodgkin's lymphomas were of T-cell origin and 4 were B-cell lymphomas. Eight out of 14 presented on a surgical emergency. Thirteen were treated using chemotherapy. The median survival from the diagnosis of enteropathy associated T-cell lymphoma was 12 months (range 1-126).

CONCLUSIONS

Lymphomas associated with coeliac disease are heterogeneous and their diagnosis is difficult. The enteropathy-associated T-cell lymphoma is the most frequent, aggressive and fatal complication of coeliac disease but it is not rare to observe association with B-cell lymphoma. Chemotherapy is highly toxic in those patients. Despite a poor prognosis, long-term survival can be expected in a fraction of these patients.