Multiple lymphomatous polyposis of the gastrointestinal tract is a heterogenous group that includes mantle cell lymphoma and follicular lymphoma: analysis of somatic mutation of immunoglobulin heavy chain gene variable region

Recent Advances in the Genetic of MALT Lymphomas

Simple Summary

Mucosa-associated lymphoid tissue (MALT) lymphoma is the most common subtype of marginal zone lymphomas. These B-cell neoplasms may arise from many organs and usually have an indolent behavior. Recurrent chromosomal translocations and cytogenetic alterations are well characterized, some of them being associated to specific sites. Through next-generation sequencing technologies, the mutational landscape of MALT lymphomas has been explored and available data to date show that there are considerable variations in the incidence and spectrum of mutations among MALT lymphoma of different sites. Interestingly, most of these mutations affect several common pathways and some of them are potentially targetable. Gene expression profile and epigenetic studies have also added new information, potentially useful for diagnosis and treatment. This article provides a comprehensive review of the genetic landscape in MALT lymphomas.

Abstract

Mucosa-associated lymphoid tissue (MALT) lymphomas are a diverse group of lymphoid neoplasms with B-cell origin, occurring in adult patients and usually having an indolent clinical behavior. These lymphomas may arise in different anatomic locations, sharing many clinicopathological characteristics, but also having substantial variances in the aetiology and genetic alterations. Chromosomal translocations are recurrent in MALT lymphomas with different prevalence among different sites, being the 4 most common: t(11;18)(q21;q21), t(1;14)(p22;q32), t(14;18)(q32;q21), and t(3;14)(p14.1;q32). Several chromosomal numerical abnormalities have also been described, but probably represent secondary genetic events. The mutational landscape of MALT lymphomas is wide, and the most frequent mutations are: TNFAIP3, CREBBP, KMT2C, TET2, SPEN, KMT2D, LRP1B, PRDM1, EP300, TNFRSF14, NOTCH1/NOTCH2, and B2M, but many other genes may be involved. Similar to chromosomal translocations, certain mutations are enriched in specific lymphoma types. In the same line, variation in immunoglobulin gene usage is recognized among MALT lymphoma of different anatomic locations. In the last decade, several studies have analyzed the role of microRNA, transcriptomics and epigenetic alterations, further improving our knowledge about the pathogenic mechanisms in MALT lymphoma development. All these advances open the possibility of targeted directed treatment and push forward the concept of precision medicine in MALT lymphomas.

Blastic Mantle Cell Lymphoma of the Gastroesophageal Junction: A Unique Presentation and Literature Review

Although vast, the medical literature is deficient in reports of gastroesophageal junction (GEJ) involvement of mantle cell lymphoma (MCL). We present the unique case of a 76-year-old male who presented with worsening dysphagia, weight loss, and heartburn and who was found to have blastic variant of MCL in the GEJ. He had undergone extensive workup in the past for an ulcerative, gastric/GEJ lesion, found on four separate esophagogastroduodenoscopies (EGDs) and two esophageal ultrasounds, whose biopsies were repeatedly negative for malignancy. On admission, physical examination and labs were unremarkable, but computed tomography showed an irregular mass involving the GEJ. EGD on admission showed a large friable, ulcerated lesion with heaped-up margins involving the GEJ whose biopsies showed histological and immunohistochemical (IHC) findings consistent with blastic MCL. A bone marrow biopsy showed minimal involvement (<5%) of CD5+/CD23+ B cells and was negative for both cyclin D1 and t(11;14). The biopsy of the lesion was diffusely infiltrated by atypical lymphocytes with prominent nucleoli and IHC stains positive for CD20, cyclin D1, BCL-2, and BCL-6 as well as a Ki-67 proliferative index >90%, all consistent with blastic MCL, a rare and aggressive subtype of MCL. He was started on guideline-based chemoimmunotherapy as he was not a candidate for stem cell transplantation. Repeat imaging 1 year later showed improvement of the mass, with negative endoscopic biopsies for lymphoma. This case provides additional distinct features to the various clinical presentations associated with this rare proliferative disorder, thereby enhancing the medical literature on MCL.

A case report of mantle cell lymphoma presenting as intussuscepting colon mass

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Primary gastrointestinal lymphomas rarely present as a single colonic mass.

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This is a case report of a single mass colonic mantle cell lymphoma causing a colon-colonic intussusception.

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Timely diagnosis and treatment of mantle cell lymphoma is critical.

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Case represents a patient whose treatment plan was unexpectedly altered from surgery after a biopsy.

Introduction

Mantle Cell Lymphoma (MCL) is a non-Hodgkin lymphoma accounting for 2.5% of lymphoid neoplasms in the United States. Primary gastrointestinal (GI) lymphomas account for 1–4% of all GI malignancies, with few reports of primary mantle cell lymphoma presenting as a single colonic mass and none to our knowledge with colon-colonic intussusception as the presenting finding. Accurate and timely diagnosis is imperative because MCL has rapid progression and early chemotherapeutic intervention results in improved patient outcomes. This work is reported in line with the SCARE criteria [1] for case report publication.

Presentation of case

A 61-year-old male presented with 1 month history of nonspecific right sided abdominal pain. Computed Tomography (CT) of the abdomen identified an intussuscepting mass in the proximal ascending colon and an additional 8 mm hepatic lesion. Colonoscopy identified a large mass in the corresponding area of colon identified on CT. Histology and immunohistochemistry of biopsied specimen diagnosed MCL.

Discussion

Planned surgical intervention was deferred and the patient was referred for oncologic treatment. We report the first case to our knowledge of MCL presenting as colon-colonic intussusception and discuss the work-up of this rare lymphoma that clinicians may be required to diagnose and manage.

Conclusion

This report serves as a reminder to maintain a broad differential inclusive of uncommon diseases and unanticipated pathology. Practicing with a thorough understanding of medical principles and clinical acumen is essential for optimal patient care and, as demonstrated in this case, preventing a potentially unnecessary surgical intervention thus delaying appropriate chemotherapy.

Mantle Cell Lymphoma with a Single Protruding Lesion as the Cause of Intussusception

Mantle cell lymphoma (MCL) is a malignant lymphoma of the gastrointestinal tract that mostly presents as multiple lymphomatous polyposis (MLP); however, MLP with intussusception is rarely reported in MCL. Furthermore, a single protruding lesion with intussusception has never been reported in primary small intestinal MCL. A 70-year-old man presented with pain in the right lower abdomen. Computed tomography and colonoscopy revealed ileocecal intussusception. Ileocecal resection was performed. Histology and immunohistochemistry of the resected specimen showed MCL with a single protruding lesion. The patient was successfully treated with surgery alone and remains in complete remission at the three-year follow-up.

A very unusual cause of dysphagia: mantle cell lymphoma

Dysphagia is an alarm symptom requiring a prompt investigation. Different benign and malignant diseases may present such a symptom. We describe a case of a 79-year-old patient who complained of fluctuating dysphagia episodes following solid food ingestion in the previous 5 months with mild weight loss. No other gastrointestinal symptoms were present. The patient was referred by the General Practitioner for a videofluoroscopic swallow examination which revealed nodularity of mucosa surface in the oropharynx, esophagus, fundus, and gastric body. Upper endoscopy confirmed the feature, also showing a normal mucosa of the antrum and duodenum. The histological examination revealed a mantle cell lymphoma (MCL). A stage III, MCL involving the esophagus and proximal stomach was eventually diagnosed. Esophageal MCL localization is extremely rare, and this is the first report showing a clinical onset with dysphagia.

Pathology of extra-nodal non Hodgkin lymphomas

In the management of extra-nodal lymphomas it is important to determine whether the tumour has disseminated and whether lymph nodes are involved. Some extra-nodal lymphomas may be the result of random spread of nodal lymphoma. Specific homing, however, determines the site of many extra-nodal lymphomas, as exemplified by cutaneous T-cell lymphomas, which seem to be derived from skin-homing T-cells and mucosa-associated lymphoid tissue lymphomas that show features of the mucosal immune system. Enteropathy-associated T-cell lymphoma is derived from mucosal T-cells in patients with coeliac disease. Immunological sanctuary accounts for the localisation of primary brain, eye and testicular lymphoma. Mantle cell lymphoma frequently causes tumours in the gastrointestinal tract. Random biopsies have shown that a high proportion of patients with this lymphoma have extensive occult involvement of the gastrointestinal tract at the time of first diagnosis. Follicular lymphoma occurs at both nodal and extra-nodal sites, but uncommonly at both sites at the same time. Extra-nodal follicular lymphomas frequently lack t(14;18)(q32;q21) and do not express bcl-2, which are characteristics of the nodal disease. At extra-nodal sites, follicular lymphoma is more likely to be curable than nodal follicular lymphoma. The behaviour of extra-nodal lymphomas cannot be assumed to follow that of their nodal counterparts.

Endoscopic findings in mantle cell lymphoma with gastrointestinal tract involvement

BACKGROUND AND AIMS

Mantle cell lymphoma (MCL) of the gastrointestinal (GI) tract is a rare disease with a poor prognosis. The aim of this study was to determine clinical and endoscopic characteristics of patients with GI MCL.

METHODS

Clinical features of 19 patients with GI MCL were reviewed along with the endoscopic findings on 27 anatomical lesions.

RESULTS

The initial presenting symptoms were abdominal pain (n = 7, 36.8%), GI tract bleeding (n = 5, 26.3%), dyspnea (n = 2, 10.5%), indigestion (n = 1, 5.3%), diarrhea (n = 1, 5.3%), cervical lymphadenopathy (n = 1, 5.3%), tonsilar mass (n = 1, 5.3%), and no symptoms (n = 1, 5.3%). On endoscopy, in 19 patients with 27 lesions, the anatomic locations of the lesions were: stomach, n = 2 (10.5%); stomach and colon, n = 7 (36.8%); terminal ileum and colon, n = 1 (5.3%); colon, n = 9 (47.4%). There was 1 fungating case (3.7%), 4 ulcerative cases (14.8%), 9 infiltrative cases (33.3%), and 13 polypoid cases (48.1%).

CONCLUSIONS

The endoscopic findings in GI MCL are variable, with common presenting manifestations of abdominal pain and GI bleeding.

Gastrointestinal follicular lymphoma: review of the literature

Gastrointestinal follicular lymphoma (GI-FL) is a relatively rare disease, accounting for only 1%-3.6% of gastrointestinal non-Hodgkin's lymphoma. Although the duodenum and terminal ileum are considered to be the most common sites of origin, the development of wireless capsule endoscopy and double-balloon enteroscopy has increased the detection of GI-FL in every part of the small intestine. Approximately 70% of patients with GI-FL are estimated to have multiple lesions throughout the entire gastrointestinal tract. FL is a low-grade lymphoma that usually develops very slowly. If the lymphoma causes no symptoms, immediate treatment may not be necessary. Standard therapy has not yet been established for GI-FL, but chemotherapy, radiotherapy, monoclonal antibody therapy, or a combination of these therapies, is sometimes performed based on the therapeutic regimens for nodal FL. Regimens including conventional chemotherapy with rituximab, which achieve high response rates in nodal FL, are commonly used for GI-FL. The long-term clinical outcome of GI-FL is unclear. The results of a few series on the long-term outcomes of patients with GI-FL treated with conventional therapy indicate a median relapse-free time ranging from 31 to 45 months. On the other hand, in patients with GI-FL who were followed without treatment, the median time to disease progression was 37.5 months. Thus, whether to initiate aggressive therapy or whether to continue watchful waiting in patients with GI-FL is a critically important decision. Ongoing research on biomarkers to guide individualized GI-FL therapy may provide invaluable information that will lead to the establishment of a standard therapeutic regimen.

Primary gastrointestinal tract mantle cell lymphoma as multiple lymphomatous polyposis

Primary gastrointestinal involvement of mantle cell lymphoma (MCL) is rare with a frequency reported between 4 and 9% of all gastrointestinal B-cell non-Hodgkin lymphomas. It was first described and so-called as multiple lymphomatous polyposis (MLP). Its clinical presentation is usually characteristic, with multiple lymphomatous polyps involving several digestive tract segments and a marked tendency towards extra-intestinal spread. The constant and typical phenotypic features of the small cleaved tumour cells, characterised as CD20+, CD5+ CD23- with a t(11;14) (q13;q32) and cyclin D1 overexpression on immunochemistry, allow MLP to be considered as the gastrointestinal counterpart of peripheral nodal MCL. They both share a very poor outcome. Response to intensive chemotherapy regimens usually results in regression of macroscopic and sometimes microscopic lesions but remissions are short and median survival from 3 to 4 years. Prognosis has been significantly improved since in younger patients, intensive front-line immunochemotherapy with autologous stem cell transplantation has been proposed. Earlier diagnosis with further studies integrating novel agents are still required to determine the optimal treatment with less toxicity.

Endoscopic follow-up of 3 cases with gastrointestinal tract involvement of mantle cell lymphoma

Gastrointestinal (GI) tract involvement of mantle cell lymphoma (MCL) presents as a variety of forms, ranging from multiple lymphomatous polyposis (MLP) to a slight mucosal change. We report 3 cases with GI tract involvement of MCL who were followed-up by endoscopy. The present study shows three new informations. MLP of the esophagus is rare, but it was observed in two of 3 patients who were extensively involved by MCL. Endoscopic follow-up in one patient suggested that lymphoma cells of MCL had invaded the lamina propria to submucosal layer before MLP developed. Two of the 3 cases showed a favorable clinical course with single-agent rituximab therapy.

Double-balloon endoscopy depicts diminutive small bowel lesions in gastrointestinal lymphoma

The aim was to determine the prevalence of small bowel involvement in patients with gastrointestinal (GI) lymphoma by double-balloon endoscopy (DBE). We examined 29 patients with primary GI lymphoma by oral and anal DBEs. Clinicopathologic features related to the prevalence of diminutive small bowel involvement and the clinical outcome were retrospectively investigated. Diminutive small bowel lesions were found in 14 patients. The prevalence of the lesions was not different between patients with primary small bowel lymphoma and those with primary extra-small bowel lymphoma (50% versus 47%, P = 0.6). However, clinical stage was more advanced in patients with the lesions than in those without (P < 0.05). The lesions were more frequently found in T-cell lymphoma (100%) and follicular lymphoma (77%) than in the other types of lymphoma (15%) (P < 0.05). Diminutive small intestinal lesions occur in patients with GI lymphoma, especially in those with follicular lymphoma and T-cell lymphoma. GI lymphomas of these histologic types are candidates for scrutiny by DBE.

Mantle cell lymphoma as a rare cause of intussusception: a report of 2 cases

Intussusception is uncommon in adults and is only very rarely caused by malignant lymphoma. To our knowledge, there are only 2 previously reported cases of mantle cell lymphoma causing intussusception. We present 2 additional cases of intussusception at the ileocecal valve in patients being treated for mantle cell lymphoma, and a review of the pertinent literature is presented.

Primary gastrointestinal follicular lymphoma: a clinicopathologic study of 13 cases from Taiwan

GOALS

Follicular lymphoma (FL) is a common nodal lymphoma. Primary gastrointestinal follicular lymphoma (GIFL) is rare and most commonly occurs in the elder women with indolent clinical course, mainly in the duodenum and terminal ileum. We conducted this study to characterize GIFL in Taiwan.

STUDY

A total of 13 cases were retrospectively collected in 4 hospitals in southern and eastern Taiwan up to 2006. Pathology review and immunohistochemistry were performed and the clinical data were obtained from chart review.

RESULTS

There were 5 men and 8 women with a median age of 58 years (range, 31 to 74; mean, 55). The most frequent site was ileum (7/13, 54%) with 4 tumors in the terminal ileum and the most common symptom was abdominal pain (8/13, 62%). Multiple lymphomatous polyposis was present in 6 patients (46%). Five (45%) of 11 tumors with surgical resection showed transmural involvement. Most of the cases revealed a predominantly follicular pattern (7/13, 54%) and low-grade disease (grades 1 and 2; 10/13, 77%). The tumors expressed CD10 (62%), Bcl-2 (77%), Bcl-6 (77%), and MUM1 (38%). Five patients (38%) were at stage IE and 8 (62%) at stage IIE. Treatment included surgery with or without chemotherapy. All patients achieved complete remission and relapse occurred in 3 patients. At a median follow-up time of 51 months (range, 3 to 180; mean, 63), 11 patients (85%) were disease free and no patient died of lymphoma.

CONCLUSIONS

We characterized the clinicopathologic features of the first series of GIFL in Taiwan. These tumors frequently involved ileum with a favorable prognosis.

Follicular lymphoma with extensive gastrointestinal tract involvement: follow-up by capsule endoscopy

Follicular lymphoma with gastrointestinal tract involvement is rare. We describe the case of a young woman with follicular lymphoma with multiple nodular lesions involving segments of the proximal jejunum and terminal ileum. The presenting symptom was chronic diarrhea. The diagnosis was made by endoscopy with histologic examination of the mucosal lesions of the proximal and distal small intestine, immunohistochemical staining, and molecular analysis. The initial spread and pattern of the small bowel involvement, as well as treatment response, were evaluated by videocapsule endoscopy. The application of molecular analysis along with immunophenotypic evaluation has made it possible to precisely diagnose follicular lymphoma. In the present case, the use of capsule endoscopy improved the evaluation of the extent of small bowel involvement prior to and following treatment.

Small Lymphoid Proliferations in Extranodal Locations

Context.—Low-grade non-Hodgkin lymphomas frequently involve extranodal sites including the gastrointestinal tract, skin, and lung, either selectively or as part of widespread dissemination. Differentiation from inflammatory or infectious conditions requires knowledge of specific histologic characteristics of the various entities as well as ancillary techniques.

Objective.—To describe the key features and provide diagnostic clues to the identification of specific extranodal low-grade lymphomas of T-cell and B-cell types including small lymphocytic lymphoma, follicular lymphoma, mantle cell lymphoma, extranodal marginal zone B-cell lymphomas of mucosal-associated lymphoid tissue, and hairy cell leukemia. Histologic and cytologic features are highlighted, as well as appropriate integration of results of ancillary diagnostic studies including flow cytometry, immunohistochemistry, molecular features, and cytogenetics.

Data Sources.—The published literature as well as personal experience from a specialized hematopathology practice at a large university medical center.

Conclusions.—Correct identification of extranodal low-grade lymphomas and differentiation from hyperplastic and inflammatory or infectious processes require the ability to distinguish each of the specific entities discussed. Ancillary studies are often indispensable in reaching a correct diagnosis.

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.

Primary gastrointestinal lymphomas: a radiological-pathological review. Part 2: Small intestine

Primary lymphoma of the small intestine is a heterogeneous group of diseases reflected in its protean imaging features. This review illustrates the widespread appearances seen on imaging methods (primarily CT and barium studies) with pathological correlation.

Cytogenetic and clinicopathological characterization by fluorescence in situ hybridization on paraffin-embedded tissue sections of twenty-six cases with malignant lymphoma of small intestine

OBJECTIVE

In small intestinal malignant lymphoma (SIML), the correlation between specific chromosomal abnormalities and clinicopathological features remains unclear. The aim of this study was to determine the frequency of chromosomal translocations involving the BCL1, BCL2, c-MYC, BCL6 and MALT1 genes by using fluorescence in situ hybridization directly on paraffin-embedded tissue sections (tissue-FISH).

MATERIAL AND METHODS

Twenty-six cases diagnosed as having SIML between 1996 and 2003 were the subjects of the clinicopathological investigation conducted in this study. Tissue-FISH was performed with specific probes on paraffin-embedded tissue sections as described previously.

RESULTS

The primary site was frequently located at the duodenum (9 cases, 35%). In accordance with the World Health Organization classification, 14 (53%) cases were diagnosed as having diffuse large B-cell lymphoma (DLBCL) and 6 (23%) as marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Macroscopically, DLBCL and MALT lymphoma displayed various macroscopic features. Cytogenetically, IGH-BCL2 translocation was detected in 3 (21%) out of 14 DLBCL cases, but in none of the MALT lymphomas. BCL6 translocation was detected in 5 (35%) of 14 DLBCL cases and in 1 (17%) of 6 MALT lymphoma cases (17%). API2-MALT1 translocation was detected in 1 (7%) of 14 DLBCL cases and in 1 (17%) of 6 MALT lymphoma cases.

CONCLUSIONS

The duodenum was preferentially involved in SIML. DLBCL and MALT lymphoma showed various macroscopic features. Tissue-FISH analysis disclosed that DLBCL is cytogenetically heterogeneous. Furthermore, our study validated tissue-FISH as an additional promising diagnostic tool for detecting specific chromosomal translocations in NHL.

Lymphomatous polyposis of the gastrointestinal tract, including mantle cell lymphoma, follicular lymphoma and mucosa-associated lymphoid tissue lymphoma

AIMS

Lymphomatous polyposis (LP) is considered to represent mantle cell lymphoma (MCL) of the gastrointestinal (GI) tract. However, a few reports have suggested that some are follicular lymphoma (FL) or mucosa-associated lymphoid tissue (MALT) lymphomas. In this study, we analysed 35 patients and clarified the clinicopathological features of LP.

METHODS AND RESULTS

Paraffin-embedded tissue samples were stained immunohistochemically and analysed by tissue-fluorescence in situ hybridization (T-FISH) for IGH/CCND1 (cyclin D1) and IGH/BCL2. The average age of the patients was 58.3 years. Over half of the cases showed gastric, duodenal, small intestinal, ileocaecal and sigmoid colonic lesions (15, 19, 15, 16 and 16 cases, respectively). Phenotypically, cases were classified into three types of MCL (cyclin D1+ CD5+ CD10-) (n=12), FL (cyclin D1- CD5- CD10+) (n=14) and MALT (cyclin D1- CD5- CD10-) (n=9). T-FISH identified 11 of the 11 examined cases with MCLs to have IGH/CCND1, while seven of 10 cases with FL had IGH/BCL2, and none of the MALT cases were positive for IGH/CCND1 or IGH/BCL2. At the study endpoint, five of 12 patients with MCL were dead, two of 14 with FL and one of nine with MALT were dead of other disease. Event-free survival analysis showed significantly poorest outcome in MCL, followed by FL, while MALT was associated with a favourable outcome (P=0.0040).

CONCLUSIONS

Our study emphasizes the importance of differentiating MCL, FL and MALT of LP in evaluating prognosis and hence the most suitable therapeutic regimen.

IgVH mutations in blastoid mantle cell lymphoma characterize a subgroup with a tendency to more favourable clinical outcome

Mantle cell lymphoma (MCL) is associated with a very unfavourable clinical course. This is particularly true for mantle cell lymphoma of the blastoid subtype (MCL-b). In order to define prognostic factors, we analysed the impact of immunoglobulin heavy chain variable (IgV H) gene somatic hypermutations on clinical outcome in a series of 21 cases of morphologically, phenotypically, and genotypically well-characterized MCL-b. Testing and estimation were performed using log-rank statistics and displayed on Kaplan-Meier graphs. Thirteen of 21 cases of MCL-b revealed a homology rate of > or = 99% compared to IgV H germ-line sequences in the databases and were scored as non-mutated. Eight of 21 cases (38%) of MCL-b were mutated. In MCL-b the mutation frequency was usually low and the mutation pattern was only rarely antigen-selected, in contrast to a control group of 11 cases with morphologically almost identical, but phenotypically and genotypically clearly distinguishable, diffuse large B cell lymphoma, derived, most likely, from germinal centre B cells. In our series of 21 MCL-b, positive IgV H mutational status, irrespective of varying homology thresholds, had no statistically significant prognostic impact on event-free or overall survival. However, mutated MCL-b tended to present more frequently at an earlier stage and without bone marrow involvement and to show lower rates of relapse and death, resulting in a more favourable clinical outcome.

Immunoglobulin heavy chain genes somatic hypermutations and chromosome 11q22-23 deletion in classic mantle cell lymphoma: a study of the Swiss Group for Clinical Cancer Research

Mantle cell lymphoma (MCL) shares immunophenotypic and karyotypic features with chronic lymphocytic leukaemia. The latter comprises two distinct entities with prognosis dependent upon immunoglobulin heavy chain (IgH) gene mutational status and the presence of 11q deletion. We evaluated the relevance of IgH gene mutational status, IgV gene family usage and presence of 11q deletion in a series of 42 histologically reviewed classical MCL cases to determine the prognostic impact. VH3 was the most common VH family, with VH3-21 being the most frequent individual VH gene. Approximately 30% of the cases had a IgH somatic mutation rate higher than 2%, but was only higher than 4% in <10% of cases. Half of the cases had deletion of chromosome 11q21-telomere (11q21->ter), with two minimal deleted regions, at 11q22.2 and 11q23.2. There was no association between 11q loss and IgH gene somatic mutation rate; the use of VH3-21 gene could be associated with a better prognosis.

Gastrointestinal lymphoma

The ability to make treatment recommendations for patients with gastrointestinal lymphoma is hampered by a lack of prospective trials and by a lack of uniformity in classification and staging. Patients with gastric diffuse large B-cell lymphoma have traditionally been treated with surgery and many physicians continue to recommend this approach. However, recent data suggest that these patients can be treated with combination chemotherapy regimens in the same manner as patients with nodal presentations of diffuse large B-cell lymphoma. There is evidence to suggest that adjuvant radiotherapy may improve the outcome for these patients. The recognition that extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue is a distinct clinicopathologic entity and the elucidation of the pathogenic role of Helicobacter pylori has revolutionized the treatment of these gastric lymphomas. Patients with localized disease should be managed with antibiotic therapy initially. Radiation therapy is extremely effective for these patients, but it should probably be reserved for patients who fail anti-H. pylori treatment.

Clinicopathological features of primary intestinal lymphoma in Taiwan: a study of 21 resected cases

In Taiwan, primary intestinal lymphomas (PIL) have rarely been reported and characterized. Using WHO classification, we retrospectively studied the clinicopathological features of PIL cases surgically resected in Taiwan. There were 21 cases, 14 males and seven females, with a median age of 66. The most common symptom at presentation was abdominal pain (n = 14; 66.7%). Six (28.6%) cases showed perforation and two (9.5%) intussusception. Two patients had multicentric tumors. The most common location was ileum (n = 11, 52.4%). Twenty cases (95.2%) were of B-cell lineage, and one (4.8%) was of T-cell lineage. These cases were classified as diffuse large B-cell lymphoma (DLBL) (n = 18; 85.7%), Burkitt lymphoma (n = 2; 9.5%), and enteropathy-type T-cell lymphoma (EATL) (n = 1; 4.8%). One case was lost to follow-up. The 1- and 2-yr survival rates of the remaining 20 patients were 44.4% and 26.7%, respectively. In conclusion, we describe the clinicopathological findings of a rare case of appendiceal DLBL and another one of ileal EATL, that have never been reported in Taiwan previously. We found that in Taiwan PIL occurred in the elderly, with a male predominance, showing a relatively aggressive clinical course, and a pattern similar to that seen in western countries, except for the absence of multiple lymphomatous polyposis.

Primary follicular lymphoma of the small intestine: alpha4beta7 expression and immunoglobulin configuration suggest an origin from local antigen-experienced B cells

Primary follicular lymphoma of the gastrointestinal tract (GI-FL) is a rare so far poorly studied entity. We analyzed four FL cases located in the small intestine and duodenum to gain insight in their pathogenesis and to find an explanation for their low tendency to disseminate outside the GI tract. GI-FLs resemble nodal FLs with respect to morphology and expression of typical GC markers such as CD10, CD38, and BCL-6. We established that the high levels of the anti-apoptosis protein BCL-2 in the tumor cells are in all cases due to a t(14;18) involving the immunoglobulin heavy chain and BCL-2 loci. Detailed immunoglobulin gene analyses on microdissected tissue samples further supported the GC-cell derivation: GI-FLs carry extensively mutated variable heavy-chain genes. The mutation patterns indicated that at some time point in development stringent antigen receptor-based selection processes must have occurred. Interestingly, three of four neoplasms expressed surface IgA, an immunoglobulin class typical of the mucosal immune system and seldom found in nodal FL. In contrast to nodal FLs, the GI-FLs expressed the alpha4beta7 integrin, an established mucosa-homing receptor also expressed by normal intestinal B and T lymphocytes and by low-grade mucosa-associated lymphoid tissue lymphomas. However, the chemokine receptor CXCR3, expressed on low-grade mucosa-associated lymphoid tissue lymphomas, was not detected on the GI-FLs or on nodal FLs. The combined data suggests that primary FL of the small intestine is a distinct entity that originates from local antigen-responsive B cells.

Diffuse nodular lymphoid hyperplasia of the large bowel without hypogammaglobulinemia or malabsorption syndrome: a case report and literature review

Diffuse nodular lymphoid hyperplasia (DNLH) of the intestine is an extremely rare lymphoproliferative disorder occasionally associated with non-Hodgkin lymphomas. We report an unusual case of DNLH of the entire colon, which resembled malignant lymphoma (particularly low-grade B-cell lymphoma) both on clinical and pathologic grounds. The patient was a 62-year-old Japanese woman who was found to have multiple polypoid lesions along the entire large intestine by colonoscopy. Abdominal computed tomography revealed hepatosplenomegaly and multiple mesenteric lymphadenopathy. Histologically, the lesion was characterized by numerous lymphoid follicles with active germinal centers and a diffuse infiltrate of lymphoid cells in the mucosa and submucosa. The present case appears to be an essentially benign condition bearing a resemblance, both clinically and histologically, to malignant lymphoma, and from which it can be distinguished by use of immunohistochemical or molecular analysis.

The evaluation of the biological behavior and grade among cases with mantle cell lymphoma

We have studied the expression of MIB-1 and prognosis in cyclin D1(CyD1)+ and CyD1- mantle cell lymphoma (MCL), and compared them to B-CLL/SLL. All cases were assigned to four groups by immunoreactivity and primary sites: (1) CyD1+ nodal MCL, 11 cases: (2) CyD1+ extranodal MCL (multiple lymphomatous polyposis, (MLP)) three cases: (3) CyD1- nodal MCL, three cases: and (4) CyD1- B-CLL/SLL, seven cases. The average of MIB-1 labeling indexes of the four groups were 30.66, 8.70, 9.30 and 4.66, respectively. The CyD1- group consisting of nodal MCL and CLL/SLL had a significantly longer median survival time (69 months) than the CyD1+ group consisting of nodal MCL and MLP (22 months, P = 0.01). These data indicate that CyD1- nodal MCL may show a lower MIB-1 labeling index, and has a better prognosis, than CyD1+ nodal MCL. In addition, a large difference in the average of MIB-1 labeling indexes between nodal MCL and MLP in the CyD1+ group was found.

Primary follicular lymphoma of the gastrointestinal tract: a clinical and pathologic study of 26 cases

Although the gastrointestinal tract represents the most common site of extranodal lymphoma, primary follicular lymphoma of the gastrointestinal tract is an uncommon and poorly defined disease. We report the clinical and pathologic features of 26 patients with primary gastrointestinal follicular lymphoma. Ten of 26 patients (38.5%) were stage IIE, and 16 patients (61.5%) were stage IE. Of the 26 patients, 13 were female and 13 were male. The age range was 26-81 years (median 54.5 years). Abdominal pain was the most common presenting symptom, seen in 12 of 24 patients (50%). Nodularity of the mucosal surface was the most common endoscopic finding, seen in 10 of 14 patients (71.4%). The majority of cases (22 of 26, 84.6%) involved small bowel, four involved colorectum alone, and two involved the ileocecal valve. Within the small bowel the duodenum was the most commonly involved site (10 cases). Transmural involvement by follicular lymphoma was identified in 11 of the 16 patients who underwent surgical resection; five showed involvement of mucosa and submucosa only. The most common histologic grade was grade 1. Thirteen of 26 cases were grade 1, ten grade 2, and three grade 3. Twenty-one of 26 cases showed a predominantly follicular growth pattern, four mixed follicular and diffuse, and one predominantly diffuse. All cases were positive for CD20 and BCL2 and negative for CD3, CD5, CD23, CD43, and cyclin D1. Twenty-four of 26 were positive for CD10. Four of four cases showed cytogenetic or molecular genetic evidence of t(14;18). Initial treatment modalities included surgery plus chemotherapy (nine cases), surgery alone (seven cases), chemotherapy alone (four cases), observation alone (four cases), and chemotherapy and abdominal radiation (one case). One case presented with rectal polyps and was treated with polypectomy. A complete response was observed in 15 of 22 cases that received treatment, and of the 15 cases, five recurred 27-60 months after the initial diagnosis. Recurrence and progression were associated with histologic transformation to diffuse large cell lymphoma in one case. No significant correlation was identified between treatment response and various clinical and pathologic features. Overall, none of the 26 patients died of lymphoma. One patient died of a concomitant pancreatic carcinoma. Of the remaining 25 patients, 14 were disease free and 11 were alive with disease at a mean follow-up of 43 months. The estimated 5-year disease-free survival was 62%, and median disease-free survival was 69 months. The estimated 5-year relapse-free survival was 54%, and the median relapse-free survival was 63 months.

Pathologic diagnosis of mantle cell lymphoma

Mantle cell lymphoma (MCL) is a clinicopathologic entity with distinctive morphologic and immunophenotypic features and a characteristic cytogenetic abnormality, the t(11;14)(q13;q32). Although MCL was recognized over 30 years ago, a lack of consensus regarding its morphologic features precluded its inclusion into non-Hodgkin's lymphoma (NHL) classification schemes until relatively recently. An accurate diagnosis of MCL is of great importance, since this tumor generally carries a poor prognosis and requires more aggressive and novel treatment regimens. In this article, we briefly overview the clinical features of MCL and then focus on the pathologic diagnosis of MCL, emphasizing morphologic findings and various ancillary techniques useful in the diagnostic workup. Involvement of lymph nodes and other sites, such as the spleen, liver, gastrointestinal tract, Waldeyer's ring, bone marrow, peripheral blood, and cerebrospinal fluid are reviewed. The diagnosis of high-grade variants of MCL is a particular challenge, as these tumors exhibit a broad spectrum of morphologic findings that can be misinterpreted as other types of NHL. The molecular basis of MCL is also briefly reviewed to highlight the biologic role of the t(11;14) and cyclin D1 overexpression in this tumor and the value of immunophenotypic and molecular methods for their detection as diagnostic aids.

Optimized cyclin D1 immunoperoxidase staining in mantle cell lymphoma

Mantle cell lymphoma (MCL) has a worse prognosis than MALT lymphoma (MALTL). Distinction between MCL and MALTL on purely morphologic grounds can be difficult. Cyclin D1 (PRAD1/bcl1) is overexpressed in MCL as a result of a t(11:14) gene rearrangement, which leads to overexpression of cyclin D1 mRNA and protein. The immunohistochemical detection of cyclin D1 in MCL has been reported by several authors to be highly specific with sensitivity ranging from 70%-100%, but diagnostic laboratories have reported difficulty in finding a reliable method for cyclin D1 immunostaining. The aim of this study was to evaluate and optimize a method for detection of cyclin D1 by paraffin section immunoperoxidase staining. Sections of routinely processed tissue from five MCL and one splenic marginal zone lymphoma (MZL) were immunostained using a mixture of two primary monoclonal antibodies and a standard avidin-streptavidin method. Antigen retrieval was performed using 1) steam heat in citrate buffer, 2) as in "1" followed by sonication for one minute, and 3) as in "2" followed by enzymatic digestion. All the above were repeated, with the additional use of catalyzed signal amplification (CSA). Later, sections of the same cases, plus three MALTL were immunostained as in "2". Steam heat antigen retrieval alone produced the best results. All MCL showed positive nuclear staining while the MZL and all MALTL were negative. Sonication did not enhance staining noticeably, whereas enzymatic digestion produced cytoplasmic staining. CSA increased background staining with no significant gain in nuclear stain intensity. We conclude that cyclin D1 immunostaining of formalin-fixed, paraffin-embedded tissue can be reliably achieved by heat induces antigen retrieval and a cocktail of two monoclonal antibodies.

Mantle cell lymphoma

OBJECTIVE

This article summarizes the most useful ancillary immunohistochemical and molecular assays for use in the diagnosis of mantle cell lymphoma.

DATA SOURCES

The English language literature was surveyed, with an emphasis on recent publications, for articles presenting key advances in the molecular characterization of mantle cell lymphomas and for series of cases testing the utility of molecular diagnostic tests. The authors' series of 26 small B-cell lymphomas, analyzed for the cyclin D1 protein by paraffin immunohistochemistry and for t(11;14) by polymerase chain reaction, is included.

CONCLUSIONS

Mantle cell lymphoma, a B-cell lymphoma now recognized in the 1994 Revised European-American Classification of Lymphoid Neoplasms (REAL) classification, is a relatively aggressive lymphoma with a poor prognosis. Its characteristic t(11;14)(q13;q32) translocation has a role in oncogenesis and has been exploited for molecular diagnostic tests, but these tests vary in sensitivity, specificity, and ease of use. Improved immunohistochemical tests are sufficient to confirm the diagnosis in most cases. Conventional cytogenetics and molecular diagnostic tests for t(11;14)-Southern blot and polymerase chain reaction analysis-may be helpful in selected cases, but are laborious or of limited sensitivity. Other methods, such as fluorescence in situ hybridization, need further development to provide faster, more sensitive diagnosis.