Enteropathy associated T-cell lymphoma and its precursor lesions

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

Gastrointestinal lymphomas: Morphology, immunophenotype and molecular features

Primary gastrointestinal lymphoma comprises 10-15% of all non-Hodgkin lymphomas and encompasses 30-40% of the total extranodal lymphomas. Approximately 60-75% of cases occur in the stomach, and then the small bowel, ileum, cecum, colon and rectum. Lymphoid neoplasms may consist of mature B, T and less commonly extranodal NK/T cells. Of these, the two most frequently encountered histologic subtypes are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), where Helicobacter pylori infection is implicated in a number of cases, and diffuse large B cell lymphoma. Several B cell lymphomas are associated with chromosomal aberrations. Enteropathy-associated T cell lymphoma, type I in particular, usually arises in a background of celiac disease. T cell gene rearrangement confirms clonality. NK/T cell neoplasms are invariably associated with Epstein-Barr virus infection and are often aggressive; thus, differentiation from a benign NK-cell enteropathy is paramount. Although incidence of other hematopoietic malignancies in the gastrointestinal tract such as plasma cell myeloma associated with amyloidosis, plasmablastic lymphoma, Hodgkin disease, histiocytic sarcoma and mast cell sarcoma is extremely rare, these entities have been documented, with the latter two demonstrating aggressive clinical behavior. Endoscopic ultrasonography is an important adjunct in disease staging and follow-up. Conservative antibiotic treatment of stage I MALT lymphomas with associated Helicobacter pylori infection achieves good clinical outcome with high remission rate. Chemotherapy, radiation and rarely surgery are reserved for advanced diseases or cases resistant to conservative therapy and those not associated with Helicobacter pylori infection.

Enteropathy-associated T cell lymphoma presenting with acute abdominal syndrome: a case report and review of literature

INTRODUCTION

Enteropathy-associated T cell lymphoma (EATL) is a rare peripheral non-Hodgkin's T cell lymphoma originating from intraepithelial T lymphocytes of the intestines. In general, this condition has a poor prognosis. A common initial presentation of this cancer which is a small intestinal perforation necessitating emergency surgery is of interest to practicing surgeons. The diagnosis is rarely made prior to pathological examination.

METHODS

We report a case of a 39-year-old African American man who presented with acute abdomen and was found to have a deep necrotic ulcer of the jejunum during exploratory laparotomy.

RESULTS

Pathological examination and laboratory results demonstrated EATL, type 2, which is not associated with celiac disease. A review of the literature on EATL is also presented.

Enteropathy-associated T-cell lymphoma (type II): a Brazilian case report

Enteropathy-associated T-cell Lymphoma (EATL) is a rare form of aggressive T-cell lymphoma. It is more prevalent in men over 60 years and the prognosis is very poor. EATL is classified into two groups based on morphology, immunohistochemistry, and genetic profile. EATL type I is highly associated with celiac disease and is more common in Western countries. EATL type II predominates over type I in Asia, where celiac disease is uncommon. We report a case of a 78-year-old previously healthy white male who presented with a 2-month history of diarrhea, weight loss and edema. The abdomen was distended and painful, and a tumor mass was palpable in the hypogastrium. Laboratory tests showed hypoalbuminemia. Serological tests for HIV, viral hepatitis and HTLV-1 were negative. The chest radiography showed pneumoperitoneum, and an exploratory laparotomy revealed perforation of the small bowel. An advanced stage (Ann Arbor IV B/Lugano IIE2B) EATL type II was diagnosed. Four cycles of chemotherapy were interspersed with several complications (anthracycline-induced cardiotoxicity, chemotherapy-induced neutropenic fever and severe sepsis). Performance status progressively worsened and he died 6 months after the diagnosis. This is an illustrative report of a rare and aggressive primary intestinal lymphoma. To the best of our knowledge, this is the first report of EATL type II in Brazil.

Early lesions in lymphoid neoplasia: Conclusions based on the Workshop of the XV. Meeting of the European Association of Hematopathology and the Society of Hematopathology, in Uppsala, Sweden

The increasing use of immunophenotypic and molecular techniques on lymphoid tissue samples without obvious involvement by malignant lymphoma has resulted in the increased detection of "early" lymphoid proliferations, which show some, but not all the criteria necessary for a diagnosis of malignant lymphoma. In most instances, these are incidental findings in asymptomatic individuals, and their biological behaviour is uncertain. In order to better characterize these premalignant conditions and to establish diagnostic criteria, a joint workshop of the European Association for Haematopathology and the Society of Hematopathology was held in Uppsala, Sweden, in September 2010. The panel reviewed and discussed more than 130 submitted cases and reached consensus diagnoses. Cases representing the nodal equivalent of monoclonal B-cell lymphocytosis (MBL) were discussed, as well as the "in situ" counterparts of follicular lymphoma (FL) and mantle cell lymphoma (MCL), topics that also stimulated discussions concerning the best terminology for these lesions. The workshop also addressed the borderland between reactive hyperplasia, and clonal proliferations such as pediatric marginal zone lymphoma and pediatric FL, which may have very limited capacity for progression. Virus-driven lymphoproliferations in the grey zone between reactive lesions and manifest malignant lymphoma were covered. Finally, early manifestations of T-cell lymphoma, both nodal and extranodal, and their mimics were addressed. This workshop report summarizes the most important conclusions concerning diagnostic features, as well as proposals for terminology and classification of early lymphoproliferations and tries to give some practical guidelines for diagnosis and reporting.

An algorithmic approach to the diagnosis of NK and T cell lymphomas

Lymphomas of natural killer (NK) and T cell lineages are uncommon disorders, although as a group they are more usually encountered in Asia compared to Western populations. In part due to their rarity, diagnosis and classification of T cell lymphomas often pose a challenge to clinicians and pathologists. Although there are morphological features that are characteristic of certain subtypes, correct classification of NK and T cell neoplasms relies heavily on the immunophenotype. With few exceptions, non-random genetic alterations such as translocations are less often seen in T cell neoplasms, adding to the diagnostic difficulty. Given these limitations, pathological diagnosis and classification of NK and T cell lymphomas are anything but straightforward. This paper attempts to present a practical algorithmic approach for the general pathologist who is confronted with these neoplasms.

Increasing incidence of enteropathy-associated T-cell lymphoma in the United States, 1973-2008

BACKGROUND

Enteropathy-associated T-cell lymphoma (EATL) is a rare lymphoma subtype that is strongly associated with celiac disease (CD), an autoimmune disease triggered by the ingestion of gluten. Because CD rates are increasing in the United States, the authors sought to determine whether the incidence rates of EATL also are increasing.

METHODS

The authors identified patients with primary, pathologically confirmed lymphoma in the Surveillance, Epidemiology, and End Results database registries from 1973 to 2008. To ensure capture of all cases of EATL, the following lymphoma subtypes, limited to the small bowel, were included: non-Hodgkin lymphoma not otherwise specified (NOS) T-cell, peripheral T-cell lymphoma NOS, and enteropathy type T-cell lymphoma, and their age-adjusted and sex-adjusted incidence rates were calculated over time. Survival was estimated using Kaplan-Meier curves.

RESULTS

In total, the authors identified 161 small bowel lymphomas that were diagnosed between 1973 and 2008. The overall age-adjusted and sex-adjusted annual incidence for all bowel lymphomas was 0.016 per 100,000 population, which increased over the study period from 0.006 to 0.024 per 100,000 population. These tumors were most common in men (age-adjusted incidence rate, 0.021 per 100,000) with the highest incidence rate in Hispanics (age-adjusted incidence rate, 0.033 per 100,000). The median overall survival was 7 months. There was no difference in survival by race/ethnicity (P = .09) or sex (P = .06).

CONCLUSIONS

The current results indicated a significant increase in the incidence of EATL in the United States, which may reflect the increasing seroprevalence of CD and better recognition of rare types of T-cell lymphomas. The incidence may continue to rise given the large ratio of undiagnosed-to-diagnosed individuals with CD in the United States.

Pathology and biology of peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCLs) represent a heterogeneous group of more than 20 neoplastic entities derived from mature T cells and natural killer (NK) cells involved in innate and adaptive immunity. With few exceptions these malignancies, which may present as disseminated, predominantly extranodal or cutaneous, or predominantly nodal diseases, are clinically aggressive and have a dismal prognosis. Their diagnosis and classification is hampered by several difficulties, including a significant morphological and immunophenotypic overlap across different entities, and the lack of characteristic genetic alterations for most of them. Although there is increasing evidence that the cell of origin is a major determinant for the delineation of several PTCL entities, however, the cellular derivation of most entities remains poorly characterized and/or may be heterogeneous. The complexity of the biology and pathophysiology of PTCLs has been only partly deciphered. In recent years, novel insights have been gained from genome-wide profiling analyses. In this review, we will summarize the current knowledge on the pathobiological features of peripheral NK/T-cell neoplasms, with a focus on selected disease entities manifesting as tissue infiltrates primarily in extranodal sites and lymph nodes.

Enteropathy-associated T-cell lymphoma: clinical and histological findings from the international peripheral T-cell lymphoma project

Few large, international series of enteropathy-associated T-cell lymphoma (EATL) have been reported. We studied a cohort of 62 patients with EATL among 1153 patients with peripheral T-cell or natural killer (NK)-cell lymphoma from 22 centers worldwide. The diagnosis was made by a consensus panel of 4 expert hematopathologists using World Health Organization (WHO) criteria. Clinical correlations and survival analyses were performed. EATL comprised 5.4% of all lymphomas in the study and was most common in Europe (9.1%), followed by North America (5.8%) and Asia (1.9%). EATL type 1 was more common (66%) than type 2 (34%), and was especially frequent in Europe (79%). A clinical diagnosis of celiac sprue was made in 32.2% of the patients and was associated with both EATL type 1 and type 2. The median overall survival was only 10 months, and the median failure-free survival was only 6 months. The International Prognostic Index (IPI) was not as good a predictor of survival as the Prognostic Index for Peripheral T-Cell Lymphoma (PIT). Clinical sprue predicted for adverse survival independently of the PIT. Neither EATL subtype nor other biologic parameters accurately predicted survival. Our study confirms the poor prognosis of patients with EATL and the need for improved treatment options.

NK-cell enteropathy: a benign NK-cell lymphoproliferative disease mimicking intestinal lymphoma: clinicopathologic features and follow-up in a unique case series

Intestinal T-cell and natural killer (NK)-cell lymphomas are clinically aggressive and can be challenging to diagnose in small endoscopic biopsies. We describe 8 patients in whom atypical NK-cell lymphoproliferative lesions mimicked NK- or T-cell lymphoma. The patients (2 men; 6 women; ages 27-68 years) presented with vague gastrointestinal symptoms with lesions involving stomach, duodenum, small intestine, and colon. At endoscopy, the lesions exhibited superficial ulceration, edema, and hemorrhage. Biopsies revealed a mucosal infiltrate of atypical cells with an NK-cell phenotype (CD56(+)/TIA-1(+)/Granzyme B(+)/cCD3(+)), which displaced but did not invade the glandular epithelium. Epstein-Barr virus-encoded RNA in situ hybridization was negative, and T-cell receptor-γ gene rearrangement showed no evidence of a clonal process. Based on an original diagnosis of lymphoma, 3 patients received aggressive chemotherapy followed by autologous bone marrow transplantation in 2. Five patients were followed without treatment. However, no patient developed progressive disease or died of lymphoma (median follow-up, 30 months). Repeat endoscopies in 6 of 8 patients showed persistence or recurrence of superficial gastrointestinal lesions. This unique entity mimics intestinal and NK-/T-cell lymphomas on endoscopic biopsies and can result in erroneous diagnosis, leading to aggressive chemotherapy. We propose the term "NK-cell enteropathy" for this syndrome of as yet unknown etiology.

Risk of non-Hodgkin lymphoma in celiac disease

CONTEXT

Celiac disease is one of the most common lifelong disorders. Non-Hodgkin lymphoma is a possible complication of celiac disease and may lead to a large portion of lymphoma cases.

OBJECTIVE

To quantify the risk for developing non-Hodgkin lymphoma of any primary site associated with celiac disease.

DESIGN AND SETTING

Multicenter, case-control study conducted between January 1996 and December 1999 throughout Italy.

PATIENTS

Cases were older than 20 years (median, 57; range, 20-92 years) with non-Hodgkin lymphoma of any primary site and histological type and were recruited at the time of the diagnosis. Controls were healthy adults (2739 men and 2981 women) from the general population.

MAIN OUTCOME MEASURE

Positive test result for class A serum antiendomysial antibody.

RESULTS

Celiac disease was diagnosed in 6 (0.92%) of 653 patients with lymphoma. Of the 6 cases, 3 were of B-cell and 3 were of T-cell origin. Four of 6 cases had lymphoma primarily located in the gut. In the control group, 24 (0.42%) had celiac disease. The odds ratio (adjusted for age and sex) for non-Hodgkin lymphoma of any primary site associated with celiac disease was 3.1 (95% confidence interval [CI], 1.3-7.6), 16.9 (95% CI, 7.4-38.7) for gut lymphoma, and 19.2 (95% CI, 7.9-46.6) for T-cell lymphoma, respectively. The risk for non-Hodgkin lymphoma for the overall population, which was adjusted for age and sex, was 0.63% (95% CI, - 0.12% to 1.37%).

CONCLUSION

Celiac disease is associated with an increased risk for non-Hodgkin lymphoma, especially of T-cell type and primarily localized in the gut. However, the association does not represent a great enough risk to justify early mass screening for celiac disease.