Mucosa-associated lymphoid tissue lymphoma of the stomach: long term outcome after local treatment

A Prospective Trial of Radiation Therapy Efficacy and Toxicity for Localized Mucosa-associated Lymphoid Tissue (MALT) Lymphoma

PURPOSE

We report the long-term results of a prospective trial conducted to determine the efficacy and safety of radiation therapy (RT) alone in treating localized mucosa-associated lymphoid tissue (MALT) lymphoma.

METHODS AND MATERIALS

Patients with localized MALT lymphoma were eligible and treated with involved field RT to doses of 24 to 39.6 Gy. Relapse-free survival (RFS) was the primary endpoint. Kaplan-Meier analysis was used to estimate RFS, progression-free survival (PFS), and overall survival (OS) defined from time of study entry. Preplanned subgroup analyses were performed based on site of involvement.

RESULTS

From 2000 to 2012, 75 patients were accrued; 73 received protocol-specified RT. Median follow-up was 9.8 years. Thirty-four patients had gastric MALT, 17 orbital, 13 head and neck nonorbit, 4 skin, and 5 disease of other sites. Thirteen of 34 patients with gastric MALT were Helicobacter pylori positive at the time of initial diagnosis and underwent 1 to 3 courses of triple antibiotic therapy. All gastric MALT patients had documented persistent MALT without H. pylori on endoscopy before enrollment in the study. All patients achieved a complete response with a median time of 3 months. Eleven patients (15%) had disease relapse, 9 of which were at sites outside the RT field with median time to progression of 38.3 months. Median PFS was 17.5 years, and median RFS and OS were not reached. The 10-year relapse-free rate was 83% (95% confidence interval [CI], 74%-93%). The 10-year PFS rate was 71% (95% CI, 60%-84%). The 10-year OS rate was 86% (95% CI, 77%-96%). RFS, PFS, and OS did not differ by disease site (P = .17, .43, and .50, respectively). All relapses were successfully salvaged. One patient developed metastatic gastric adenocarcinoma and was found to also have recurrent MALT on biopsy. Otherwise, all relapsed patients were alive without evidence of disease at last follow-up, and no patient died of MALT lymphoma. Sixty-seven patients (92%) experienced acute toxicity during radiation, all of which were grade 1 and 2, with only 1 grade 3 toxicity. Twenty-two patients (30%) experienced late toxicity, with only 1 grade 3 toxicity.

CONCLUSIONS

This prospective study confirms that RT for MALT lymphoma provides excellent long-term RFS with acceptable rates of toxicity. Current efforts are focused on RT de-escalation in an effort to further avoid treatment-related morbidity. CLINICALTRIALS.GOV: NCT04465162.

An Aggressive Form of MALT Lymphoma of the Stomach with Pancreas Infiltration

Introduction:

MALT lymphoma accounts for 7-8% of all B-cell lymphomas and at least 50% of primary gastric lymphoma, with the highest incidence at between 50 and 60 years of age. Aggressive forms are rare, as are indications for multi-visceral resection.

Case study:

A patient, 33 years old, was admitted to the tertiary hospital due to a biopsy at a small community hospital confirming adenocarcinoma of the stomach. She was Helicobacter pylori positive. CT showed thickening of the fundus and corpus wall, up to 2.7. cm., with numerous lymph nodes, along the small curvature and in the peripancreatic region, up to 1.5 cm in size. There was close contact between the changed and tumorous posterior wall of the stomach and the anterior surface of the pancreas. Neoplasm of the stomach was found that had infiltrated the body and tail of the pancreas and spleen hilum. Infiltration of the left crura of the diaphragm was also found, ex tempore biopsy showed inflammatory infiltration without elements of neoplasm. Total gastrectomy with omentectomy, and subtotal pancreatectomy and splenectomy were performed. Definitive patho-histological diagnosis confirmed MALT lymphoma of the stomach with pancreas infiltration, but no tumor cells were found on the spleen. Additional staining and immunohistological examination of the specimen from the community hospital showed that this was a misdiagnosis of carcinoma, and the specimen also contained MALT lymphoma.

Discussion:

MALT lymphoma frequently occurs in the stomach. For patients with MALT, systematic staging is indicated. If MALT is considered in the differential diagnosis, multiple random systematic biopsies within the stomach wall are needed to optimize diagnostic accuracy. Samples should be subject to immune phenotype analysis6. The main tumor cells of MALT are: CD 20+, CD 5-, CD 10-, CD 23-, CD 43+-. It is obvious that this kind of analysis cannot be accomplished in a small community hospital in a poor country such as Bosnia and Herzegovina, and suspicion of MALT indicates referral to a tertiary center. Although the long term risk of transformation of MALT lymphoma into the aggressive form is low9, this case of the aggressive form of MALT indicates the importance of systematic staging.

A journey into insidious world of MALT lymphoma of the ileum: from the beginning to the end

INTRODUCTION

Lymphoma of the mucosa-associated lymphoid tissue (MALT) has been used to describe a marginal zone B-cell lymphoma derived from gastrointestinal lymphoid tissue. mucosa-associated lymphoid tissue lymphoma (MALToma) of the ileum are extremely rare and only few reports with endoscopic features have been reported.

CASE STUDY

We present a 55-year-old male patient with history of abdominal pain and loss of appetite since 2½ years. Abdomino-pelvic ultrasonography was normal, but computed tomography (CT) scan of the abdomen showed, dilated segment of ileum containing both contrast and debris. He underwent segmental resection of ileum associated with stricture site, histopathology of which revealed MALToma of ileum. Patient was subsequently treated with low dose chemotherapy and strictly followed up.

DISCUSSION

Primary treatment possibility should be considered as the treatment of H. pylori infection while surgical resection for superficial lesions followed by low dose chemotherapy is recommended. The present case report explore MALToma of the GI tract, its diagnostic criterions, role of radiological and pathological tools, various investigative techniques and role of surgery and chemotherapy in such cases.

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue with amyloid deposition: a clinicopathologic case series

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is a mature B-cell neoplasm that typically follows an indolent clinical course. Amyloid deposition associated with MALT lymphoma is uncommon. We describe the clinical and pathologic features of 20 cases of MALT lymphoma and associated amyloid deposition across diverse primary sites. Frozen section immunofluorescence performed on 4 cases suggests that these deposits are a localized form of AL amyloid. Clinical follow-up was available for 15 patients. Amyloid deposits distant from the initial site occurred in 5 cases, always at sites also involved by the underlying lymphoma. No definitive evidence of systemic amyloidosis affecting the heart, kidneys, or liver was present in any patient. Given the generally indolent clinical behavior of MALT lymphomas with associated amyloid, we do not recommend extensive follow-up testing for systemic amyloidosis or more aggressive therapy than would be indicated for other MALT lymphomas of similar clinical stage.

Treatment of gastric marginal zone lymphoma of MALT type

IMPORTANCE OF THE FIELD

Gastric marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT type) represent approximately half of all cases of lymphomas arising in the stomach. They have been strongly associated with chronic Helicobacter pylori (H. pylori) gastritis. Treatment aimed at eradicating this infection results in lymphoma remissions in the majority of patients (approximately 80%) and this represents a unique case of anticancer treatment based on the eradication of the causing factor.

AREAS COVERED IN THIS REVIEW

The effects of H. pylori eradication in suppressing the growth of this lymphoma with particular emphasis on the long-term disease control results are presented in this review. Trials of different treatment modalities for patients not responding to antibiotics are also covered.

WHAT THE READER WILL GAIN

Understanding of the effects of H. pylori eradication on suppressing the growth of gastric MALT lymphoma. Readers will learn how to distinguish between clinical, histological and molecular remission of the lymphoma and will learn alternative treatments for patients with H. pylori-negative disease and for cases not responding to eradication.

TAKE HOME MESSAGE

Gastric MALT lymphoma has an indolent course and most patients can achieve durable disease control after only anti-H. pylori therapy. For patients not responding to antibiotics, randomized trials are needed to define the best treatment modality.

Mucosa-associated lymphoid tissue lymphoma and concurrent adenocarcinoma of the prostate

Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the prostate is a rare disease that characteristically follows an indolent course. It is believed that infection or chronic inflammation may be triggers for malignant transformation in the prostate, but it is of unknown etiology. Reports of MALT lymphomas of the prostate with other concurrent primary prostate cancers are even more limited. We present the unique case of a 67-year-old male with concurrent adenocarcinoma of the prostate and primary MALT lymphoma of the prostate. The patient was treated with standard therapy for prostate adenocarcinoma, which would also treat a primary MALT lymphoma. He has been disease-free for over one year for both his primary malignancies. This case confirms that MALT lymphoma can arise concurrently with adenocarcinoma of the prostate.

Overview of lymphoma diagnosis and management

The malignant lymphomas, including both Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL), represent a diverse group of diseases that arise from a clonal proliferation of lymphocytes. Each of the more than 30 unique types of lymphoma is a disease with a distinct natural history. This biologic heterogeneity gives rise to marked differences among the lymphomas with respect to epidemiology, pathologic characteristics, clinical presentation, and optimal management. This article emphasizes the principles of diagnosis, including appropriate pathologic evaluation and staging considerations, and focuses on the clinical presentation, staging, and optimal management strategies for the most common types of lymphoma.

Extranodal lymphoma

Lymphomas arising in extranodal sites are intriguing. The types of lymphomas encountered vary widely from one extranodal site to another. For many types of extranodal lymphomas, there are distinctive clinicopathologic features, sometimes including association with an underlying immunodeficiency syndrome, autoimmune disease, infection, or other immunologic disorder, or a predilection to affect patients of certain ethnic origins. Presented below is a review of lymphomas that are encountered most often in extranodal sites.

Radiotherapy for 41 patients with stages I and II MALT lymphoma: a retrospective study

PURPOSE

Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinct disease with specific clinical and pathologic features that may affect diverse organs. We analyzed our recent experience with Stage I/II MALT lymphoma presenting in the stomach and other organs to assess the outcome following radiation therapy (RT) alone.

PATIENTS AND METHODS

Forty-one patients with Stages I (37) and II (4) disease were treated between 2000 and 2006. Patients with transformed MALT were excluded. The median age was 60 years (range, 25-86 years), male: female ratio 1:1. Presenting sites included stomach, 11; orbital adnexa, 21; thyroid, 1; other head and neck, 3; small bowel, 3; skin, 1; and rectum, 1. Thirty-five patients (85%) received RT-alone and 6 (15%) received antibiotics followed by RT. RT dose was 30Gy in 20 fractions (fr) in all 41 patients. Mean follow-up time was 32.0 months (range, 2.1-162 months).

RESULTS

A first complete response was achieved in all 41 patients. Only one patient died from bile duct carcinoma at 22 months from the start of irradiation for conjunctiva MALT lymphoma without recurrence of lymphoma. The other 40 patients were alive. Thirty-eight patients out of them were alive without recurrence. One patient with a duodenal lymphoma had a recurrence in non-irradiated distant sites at 1 month. Another patient with a bilateral eye lid lymphoma had a recurrence within radiation field at 41 months. The absolute local control rate with radiation was 98% (40/41 patients).

CONCLUSION

Localized MALT lymphomas have excellent prognosis following moderate-dose RT (30Gy/20fr).

Low-grade non-hodgkin lymphomas

The most common low-grade non-Hodgkin lymphomas are of B-cell origin. This review will focus on follicular lymphomas and extranodal marginal zone lymphomas, also known as mucosa-associated lymphoid tissue (MALT) lymphomas. These are radiation-sensitive lymphomas. Moderate doses (30-35 Gy) for these stage I and II low-grade lymphomas result in long-term local control and possible cure. Involved-field radiation therapy is the standard approach and produces minimal morbidity. However, a significant proportion of patients relapse with systemic disease outside of radiation fields. For follicular lymphoma, this occurs in approximately 50% of patients after 15 years and for nongastric MALT lymphoma 30% to 40% after 10 years. Patients with relapsed disease are not curable with chemotherapy, but the disease often remains indolent and prolonged survival is observed. For gastric MALT lymphomas associated with Helicobacter pylori but which did not respond to antibiotic therapy, radiation treatment is indicated and almost always curative. For localized MALT lymphomas not related to microorganisms, radiation therapy is the initial standard therapy regardless of anatomic location. Patients with stage III and IV low-grade lymphoma and local symptoms are often successfully palliated with a low dose regimen of 2 x 2 Gy (total dose 4 Gy).

A multicenter phase II study of local radiation therapy for stage IEA mucosa-associated lymphoid tissue lymphomas: a preliminary report from the Japan Radiation Oncology Group (JAROG)

PURPOSE

The aim of this study was to evaluate the efficacy and toxicity of moderate dose radiation therapy (RT) for mucosa-associated lymphoid tissue (MALT) lymphoma in a prospective multicenter phase II trial.

METHODS AND MATERIALS

The subjects in this study were 37 patients with MALT lymphoma between April 2002 and November 2004. There were 16 male and 21 female patients, ranging in age from 24 to 82 years, with a median of 56 years. The primary tumor originated in the orbit in 24 patients, in the thyroid and salivary gland in 4 patients each, and 5 in the others. The median tumor dose was 30.6 Gy (range, 30.6-39.6 Gy), depending on the primary site and maximal tumor diameter. The median follow-up was 37.3 months.

RESULTS

Complete remission (CR) or CR/unconfirmed was achieved in 34 patients (92%). The 3-year overall survival, progression-free survival, and local control probability were 100%, 91.9%, and 97.3%, respectively. Thirteen patients experienced Grade 1 acute toxicities including dermatitis, mucositis, and conjunctivitis. One patient developed Grade 2 taste loss. Regarding late toxicities, Grade 2 reactions including hypothyroidism, and radiation pneumonitis were observed in three patients, and Grade 3 cataract was seen in three patients.

CONCLUSIONS

This prospective phase II study demonstrated that moderate dose RT was highly effective in achieving local control with acceptable morbidity in 37 patients with MALT lymphoma.

Non-Hodgkin's lymphoma of mucosa-associated lymphoid tissue

The concept of mucosa-associated lymphoid tissue (MALT) lymphomas was introduced by Isaacson and Wright [Cancer 1983; 52:1410-1416] in 1983. After more than 20 years of clinical research MALT lymphomas are now recognized as a distinct subtype of non-Hodgkin's lymphoma (NHL) with unique pathogenic, histological, and clinical features. Although this subtype of NHL occurs frequently, optimal management remains elusive. This manuscript reviews features of the clinical presentation, diagnosis, pathology, molecular characteristics, and management of both gastric and non-gastric MALT lymphoma.

Detection of the t(11;18) API2/MALT1 translocation associated with gastric MALT lymphoma in routine formalin-fixed, paraffin-embedded small endoscopic biopsy specimens by robust real-time RT-PCR

The t(11;18)(q21;q21) API2/MALT1 translocation is a specific chromosomal abnormality in extranodal marginal B-cell lymphomas of the mucosa-associated lymphoid tissue (MALT) type, particularly in those occurring in the stomach and lungs. Identification of t(11;18) may aid in the diagnosis of MALT lymphoma and strongly predicts resistance of gastric MALT lymphoma to Helicobacter pylori eradication therapy. We developed a robust real-time reverse transcription-polymerase chain reaction (RT-PCR) procedure to efficiently detect t(11;18) in virtually all types of specimens used in routine diagnostic workups. We blindly tested 40 samples from 38 patients with gastric MALT lymphoma; 10 (25%) of 40 samples, or 8 (21%) of 38 patients were positive for t(11;18). In contrast, t(11;18) was not detected in 8 cases of gastric large B-cell lymphoma, 11 cases of chronic active gastritis, and 16 samples unrelated to lymphoma. Our findings suggest that real-time RT-PCR for t(11;18) may be a valuable tool with much relevance in the current clinical management scheme.

Primary extranodal lymphomas of gastrointestinal localizations: a single institution 5-yr experience

This study is aimed at comparison of patients with extranodal lymphomas based on pathohistological findings differences (MALT vs non-MALT) as well as regarding gastric and non-gastric localization, and determining the significance of clinical-laboratory parameters with respect to therapeutic response and length of survival. A total of 56 patients with extranodal non-Hodgkin's lymphomas of the gastrointestinal tract were evaluated over a 5-yr period. Regarding the localization of the disease, the stomach was most frequently affected, 39 patients (70%); followed by small and large intestines, 17 patients. As for the pathohistological findings, MALT lymphoma accounted for 70%, DLBCL 25%, while other subtypes accounted for 5%. Patients' distribution was analyzed according to CS based on both Ann Arbor and Lugano systems; however, the difference obtained between the groups was not statistically significant in both staging types of patients. Statistically significant difference in patients' distribution was not found with respect to IPI index, bone marrow infiltration, anemia, hypoalbuminemia, or histological subtype and localization. Difference in survival between patients according to the pathohistological type was not statistically significant also according to the type of the affected gastrointestinal tract organ. Statistical significance of difference according to survival probability was obtained based on age (survival is longer in patients over 55 yr of age); according to CS and according to Ann Arbor and Lugano classifications (the patients with lower CS live significantly longer); according to IPI index (the survival is significantly longer in patients with lower probability: IPI-0,1, and 2), as well as patients free of bone marrow infiltration whose survival is also significantly longer.

Curative resection plus adjuvant chemotherapy for early stage primary gastric non-Hodgkin's lymphoma: a retrospective study with emphasis on prognostic factors and treatment outcome

BACKGROUND

There is controversy regarding the optimal therapy for primary non-Hodgkin gastric lymphoma with some authors defending surgical extirpation either alone or in association with radiotherapy and or chemotherapy, especially in relation to the earlier stages of the disease.

AIM

To analyze the clinical-pathological features and the results of management approaches for patients with primary early-stage non-Hodgkin's lymphoma of the stomach operated in Surgical Gastroenterology Department, "Hospital do Servidor Público Estadual", São Paulo, SP, Brazil. The literature is reviewed to highlight the aspects of diagnosis, prognostic factors and role of the various treatment regimens.

METHOD

Sixteen patients with primary early-stage gastric lymphoma underwent curative surgical treatment. The variables analyzed were age, sex, location, size, type of surgery, number of lesions, depth of invasion, histological type in accordance with Kiel's classification, involvement of lymph nodes, Ann Arbor stage classification modified by Musshoff and Schmidt-Vollmer, histological grade, margins, adjuvant therapy, clinical course and survival.

RESULTS

Ten patients (62.5%) underwent subtotal gastrectomy and six (37.5%) underwent total gastrectomy. The majority (9/56.2%) of the lesions were located in the antrum. Single lesions (10/62.5%) were more frequent than multiple lesions (6/37.5%). Thirteen patients (81.2%) were classified as stage IE and three (18.7%) as stage IIE1. Primary gastric lymphoma classified histologically as low or high grade was presented by 10 (62.5%) and 6 (37.5%) patients, respectively. The most frequent histological types were the lymphoplasmocytic cytoid (4/25.0%) and centroblastic (4/25.0%). Ten patients (62.5%) received adjuvant treatment (chemotherapy and/or radiotherapy). Nine patients (56.2%), all in stage IE, reached a survival greater than 5 years and of these eight (50.0.%) had received adjuvant therapy. Two (12.5%) patients with stage IIE1 presented peritoneal relapse and died 3.0 years and 3.5 years after their respective operations. The mean overall survival was 42.5 months.

CONCLUSIONS

Among the patients with primary early-stage gastric lymphoma (IE and IIE1), the gastric resection enabled an accurate clinicopathological staging, in addition to obtaining sufficient material for histopathological study and extirpation of the lesion. Furthermore, for patients with stage IE disease, the gastric resection combined with adjuvant therapy was associated with a greater than 5-year survival. Until prospective randomized studies are realized in order to evaluate the real efficacy of the different types of treatment for primary early-stage gastric lymphoma, management approaches should be individually tailored.

Radiation therapy for localized low-grade non-Hodgkin's lymphomas

The most common low grade B-cell non-Hodgkin's lymphomas are follicular lymphomas, and extranodal marginal zone lymphomas, also known as mucosa-associated lymphoid tissue (MALT) lymphomas. Localized presentations of follicular lymphoma occur in 20-30% of cases, while for MALT lymphomas, stage I-II disease presentations occur in 70-90%. These are radiation-sensitive lymphomas. Following moderate dose local radiation treatment (30-35 Gy) for these stage I and II low grade lymphomas, the clinical results indicate long-term local control and possible cure. While local control is achieved with minimal morbidity with involved-field radiation therapy, a significant proportion of patients relapse with systemic disease outside of radiation fields. For follicular lymphoma, this occurs in approximately 50% of patients after 15 years, and for non-gastric MALT lymphoma, 30-40% after 10 years. Although patients with relapsed systemic disease are not curable with chemotherapy, the disease often behaves in an indolent fashion and prolonged survival is observed. For gastric MALT lymphomas, radiation therapy is indicated in patients whose lymphoma did not respond to Helicobacter pylori eradication therapy, or in gastric lymphoma not related to this microorganism. The subject of causative agents responsible for non-gastric MALT lymphomas is under active study and the identification of putative microorganisms will lead to improved treatment strategies for these unusual lymphomas, similar to the success in gastric lymphomas over the last decade.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach: results of a controlled clinical trial

Treatment of patients with early stage gastric mucosa-associated lymphoid tissue (MALT) remains undefined. We began a controlled clinical trial to evaluate efficacy and toxicity of the most common therapies. Two hundred and forty-one patients with gastric low-grade MALT lymphoma in early stage (IE and IIE) were randomized to surgery (80 cases), radiotherapy (78 cases), and chemotherapy (83 cases). With a median follow-up of 7.5 yr, actuarial curves at 10 yr showed that event-free survival was 52% in patients treated with surgery, 52% in radiotherapy arm, and 87% in the chemotherapy group (p < 0.01). However, overall survival did not showed any statistical differences: 80%, 75% and 87%, respectively (p = 0.4). Acute and late toxicities were mild. No death-related treatments were observed. No clear differences were observed between the most common therapies in patients with primary gastric MALT lymphoma in early stages, probably because this type of lymphoma has an high response rate to salvage treatment after failure to local treatment (surgery and radiotherapy). Thus considered, chemotherapy alone is an effective and safe therapeutic approach in this setting of patients. Surgery or radiotherapy will be reserved to patients that are not candidates for chemotherapy.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach: results of a controlled clinical trial

Treatment of patients with early stage gastric mucosa-associated lymphoid tissue (MALT) remains undefined. We began a controlled clinical trial to evaluate efficacy and toxicity of the most common therapies. Two hundred and forty-one patients with gastric low-grade MALT lymphoma in early stage (IE and IIE) were randomized to surgery (80 cases), radiotherapy (78 cases), and chemotherapy (83 cases). With a median follow-up of 7.5 yr, actuarial curves at 10 yr showed that event-free survival was 52% in patients treated with surgery, 52% in radiotherapy arm, and 87% in the chemotherapy group (p < 0.01). However, overall survival did not showed any statistical differences: 80%, 75% and 87%, respectively (p = 0.4). Acute and late toxicities were mild. No death-related treatments were observed. No clear differences were observed between the most common therapies in patients with primary gastric MALT lymphoma in early stages, probably because this type of lymphoma has an high response rate to salvage treatment after failure to local treatment (surgery and radiotherapy). Thus considered, chemotherapy alone is an effective and safe therapeutic approach in this setting of patients. Surgery or radiotherapy will be reserved to patients that are not candidates for chemotherapy.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach: results of a controlled clinical trial

Treatment of patients with early stage gastric mucosa-associated lymphoid tissue (MALT) remains undefined. We began a controlled clinical trial to evaluate efficacy and toxicity of the most common therapies. Two hundred and forty-one patients with gastric low-grade MALT lymphoma in early stage (IE and IIE) were randomized to surgery (80 cases), radiotherapy (78 cases), and chemotherapy (83 cases). With a median follow-up of 7.5 yr, actuarial curves at 10 yr showed that event-free survival was 52% in patients treated with surgery, 52% in radiotherapy arm, and 87% in the chemotherapy group (p < 0.01). However, overall survival did not showed any statistical differences: 80%, 75% and 87%, respectively (p = 0.4). Acute and late toxicities were mild. No death-related treatments were observed. No clear differences were observed between the most common therapies in patients with primary gastric MALT lymphoma in early stages, probably because this type of lymphoma has an high response rate to salvage treatment after failure to local treatment (surgery and radiotherapy). Thus considered, chemotherapy alone is an effective and safe therapeutic approach in this setting of patients. Surgery or radiotherapy will be reserved to patients that are not candidates for chemotherapy.

Mucosa-associated lymphoid tissue lymphoma in the appendix, a lead point for intussusception

Abstract Appendiceal intussusception and mucosa-associated lymphoid tissue lymphoma are both uncommon entities, and this is the first report of the two occurring concomitantly in an 8-year-old boy. This report of a mucosa-associated lymphoid tissue lymphoma localized in the appendix has not been reported previously.

Conservative management of gastric lymphoma: the treatment option of choice

The study was initiated to assess the safety and effectiveness of primary chemotherapy (CHT) followed by radiotherapy (RT) compared to surgery prior to CHT and/or RT in the management of localized gastric lymphoma. Ninety-two patients treated between 1985 and 2000 were included in a retrospective analysis. Sixty patients received primary CHT followed by extended field or involved field RT. Thirty-two patients had undergone primary surgery prior to referral and were treated with curative or consolidative CHT and/or RT. CHT was carried out according to the CHOP or COP-Blam protocol. Median age was 60 years (29-85). Forty patients had tumor stage IE, 36 II1E and 16 II2E (Musshoff classification). MALT histology was present in 25, diffuse large-cell in 62, lymphoplasmocytic in 4 cases and follicular histology in 1 case. Five-year disease-specific survival was 93% both after primary CHT and after primary surgery (P = 0.8). Five-year relapse-free survival was 91% and 93%, respectively (P = 0.7). No patient experienced gastric perforation or bleeding during CHT. Primary CHT of localized gastric lymphoma is associated with a low risk of treatment-related complications. Survival was similar compared to patients initially treated with surgery. To avoid long-term sequelae after gastric resection, primary CHT is recommended as standard initial treatment in localized gastric lymphoma.

Les lymphomes gastriques du MALT

INTRODUCTION

The stomach is the most common site involved in primary gastrointestinal lymphoma. Gastric lymphoma originates from the mucosa-associated lymphoïd tissue so called MALT. It comprises a group of distinctive clinicopathological entities which are important to consider for clinical management.

CURRENT KNOWLEDGE AND KEY POINTS

In recent years, new diagnostic tools and new treatment strategies have improved the overall prognosis. One of the most exciting recent discoveries is the hypothesis that an infection by a bacterium, Helicobacter pylori has a decisive role in gastric lymphoma.

FUTURE PROSPECTS AND PROJECTS

Recent advances, essentially due to molecular biology and cytogenetic studies may emerge with the understanding of pathogenesis and new prognostic factors of these different types of gastric lymphomas. It is the aim of our oncoming studies together with the evaluation of the new therapeutic options such as radiotherapy and monoclonal antibodies in prospective studies.

Ocular adnexal lymphoma: Clinical behavior of distinct World Health Organization classification subtypes

PURPOSE

To evaluate the clinical behavior and treatment outcome of ocular adnexal lymphomas classified by the World Health Organization system, with emphasis on marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT).

MATERIALS AND METHODS

The clinicopathologic materials from 98 consecutive patients treated for ocular adnexal lymphoma were reviewed. Fourteen patients had prior lymphoma and 84 patients had primary disease (75% Stage I, 6% Stage III, and 19% Stage IV). Radiation (photons/electrons) was administered to 102 eyes to a median dose of 30.6 Gy. The mean follow-up was 82 months.

RESULTS

The most common subtypes among the primary patients were MALT (57%) and follicular (18%) lymphoma. The 5-year actuarial local control rate in 102 irradiated eyes was 98%. Among the low-grade lymphomas, the 5-year local control rate correlated with the radiation dose in the MALT lymphoma subgroup (n = 53): 81% for <30 Gy and 100% for > or =30 Gy (p <0.01). For the non-MALT low-grade lymphomas such as follicular lymphoma (n = 30), the local control rate was 100% regardless of dose. For 39 Stage I MALT lymphoma patients treated with radiation alone, the distant relapse-free survival rate was 75% at 5 years and 45% at 10 years. Distant relapses were generally isolated and successfully salvaged by local therapy. The overall survival for this subgroup was 81% at 10 years, with no deaths from lymphoma.

CONCLUSIONS

Dose-response data suggest that the optimal radiation dose for MALT lymphoma of the ocular adnexa is 30.6-32.4 Gy in 1.8-Gy fractions and follicular lymphoma is adequately controlled with doses in the mid-20 Gy range. The substantial risk of distant relapse in Stage I ocular adnexal MALT lymphoma underscores the importance of long-term follow-up for this disease and the need for additional comparative studies of MALT lymphoma of different anatomic sites.

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.

Gastric irradiation for low-grade MALT lymphoma of the stomach: report of two cases and review of the literature

We report the case history of two patients treated with primary gastric irradiation for localized low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach that failed to respond to anti-Helicobacter pylori antibiotics. One patient refused gastrectomy and the other was considered unfit for surgery. Both patients obtained a biopsy-confirmed complete response and are well and disease free after a median follow-up time of 28 months. A review of the literature on the treatment options for this condition has been undertaken. Gastric irradiation is an effective and safe alternative to gastrectomy in the treatment of low-grade MALT lymphoma of the stomach with the added advantage of organ preservation.

The importance of endoscopic ultrasonography in the management of low-grade gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND

Anti-Helicobacter pylori therapy has been reported to cause regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma in a high percentage of patients. However, in some patients, these lesions persist despite antibiotic treatment.

AIM

To determine the various endosonographic findings that may predict the regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma post-antibiotics.

METHODS

Seventy-six patients with Helicobacter pylori-positive gastric mucosa-associated lymphoid tissue lymphoma were studied. Follow-up data were available on 51 patients. All patients were treated with antibiotics. Participants underwent pre- and post-anti-Helicobacter pylori therapy endoscopy with gastric biopsies, followed by endoscopic ultrasonography examination of the stomach.

RESULTS

Helicobacter pylori was eradicated in 45 of 51 (88%) patients. At the 2-year follow-up, complete regression of mucosa-associated lymphoid tissue lymphoma was seen in 28 of 51 (55%) patients: 12 of 16 (75%) patients in stage T1m N0, 11 of 19 (58%) patients in stage T1sm N0, four of eight (50%) patients in stages T1m N1 and T1sm N1, and one of four (25%) patients in stage T2 N0. None of the stage T2 N1 patients achieved clinical regression.

CONCLUSIONS

Endoscopic ultrasonography evaluation of gastric mucosa-associated lymphoid tissue lymphoma plays a pivotal role in the initial staging and post-treatment follow-up evaluation of these lesions. Accurate staging is essential in the determination of the optimal treatment modality.

Treatment of extranodal lymphomas

At least one-quarter of the non-Hodgkin's lymphomas arise primarily at extranodal sites. The rising incidence of non-Hodgkin's lymphomas, observed over recent decades, have mainly affected the primary extranodal entities. Survival rates vary among the specific sites of primary extranodal lymphomas. This is due partly to differences in natural history, related mainly to the histological type but also to differences in management strategy which are related to organ-specific problems. Few controlled studies facilitate therapeutic decisions in this setting. This chapter represents a general overview of the available data.

Lymph nodes in gastric B-cell lymphoma: pattern of involvement and early histological changes

AIMS

This study aims to analyse the histological pattern of nodal involvement in gastric B-cell lymphoma and to detect early involvement of the lymph nodes.

METHODS AND RESULTS

Histological findings of 37 resected primary gastric lymphomas with 1313 regional lymph nodes were analysed. The primary tumour was classified into four groups: MALT lymphoma, MALT lymphoma with a minor large B-cell lymphoma (<20%), large B-cell lymphoma with MALT lymphoma, and large B-cell lymphoma without MALT lymphoma. Histological patterns of nodal involvement were divided into sinusoidal, subsinusoidal/marginal, follicular, and diffuse patterns. Semi-nested polymerase chain reaction (PCR) analysis for IgH gene rearrangement was performed. Nodal involvement was found in 2/13 (15%) MALT lymphomas, 5/6 (83%) MALT lymphomas with a minor large B-cell lymphoma, 9/12 (75%) large B-cell lymphomas with MALT lymphoma, and 6/6 (100%) large B-cell lymphomas without MALT lymphoma. The MALT lymphoma and MALT lymphoma with a minor large B-cell lymphoma showed a predominantly sinusoidal and subsinusoidal pattern, whereas diffuse pattern predominated in large B-cell lymphomas without MALT lymphoma and large B-cell lymphomas with MALT lymphoma. The follicular pattern was least common, being observed in 10.2% of large B-cell lymphomas without MALT lymphoma and large B-cell lymphomas with MALT lymphoma. Sinusoidal obliteration with permeation of small monocytoid cells into subsinusoidal zone is a characteristic finding suggesting early nodal involvement of MALT lymphoma.

CONCLUSIONS

Histological patterns of nodal involvement in gastric B-cell lymphoma vary according to the histological grade. Immunostaining for CD20 with or without PCR analysis for IgH gene rearrangement would be a useful ancillary method to confirm lymphomatous involvement.

Treatment outcome of mucosa-associated lymphoid tissue/marginal zone non-Hodgkin's lymphoma

PURPOSE

To evaluate the treatment outcome in patients with mucosa-associated lymphoid tissue (MALT)/marginal zone (MZ) non-Hodgkin's lymphoma (NHL).

MATERIALS AND METHODS

Between 1986 and 2000, 66 patients with clinical stage (CS) I-IV MALT/MZ NHL were treated; these comprise the study population. The progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier technique. Forty-five patients (68%) had CS I-II and 21 (32%) had CS III-IV disease. Twenty-nine of the 45 CS I-II patients received radiation therapy (RT) alone, and 6 patients had surgery and RT. The median RT dose was 3350 cGy. Among the 21 CS III-IV patients, treatment included chemotherapy alone (15), chemotherapy + RT (3), surgery (1), surgery + chemotherapy (1), and RT alone (1). Median follow-up was 48 months.

RESULTS

All 35 early-stage and all 4 advanced-stage patients who received RT as part of initial treatment achieved local control. Among the 63 evaluable patients, the 5-year OS and PFS were 90 and 57%, respectively. The 5-year OS was 93% and PFS was 75% among CS I-II patients; the corresponding estimates in CS III-IV patients were 83% and 14%, respectively.

CONCLUSION

Modest doses of RT provide excellent local control in patients with MALT/MZ NHL. The poor PFS in advanced-stage patients suggests the need to develop alternative systemic treatment strategies for this disease.

Gastric mucosa-associated lymphoid tissue lymphoma: spectrum of findings at double-contrast gastrointestinal examination with pathologic correlation

Mucosa-associated lymphoid tissue (MALT) is found in the surface epithelium of the stomach. MALT lymphoma is extranodal lymphoma originating from MALT. In the stomach, a strong association with Helicobacter pylori infection has been demonstrated. Low-grade gastric MALT lymphoma has been reported to have variable features at upper gastrointestinal (UGI) examination. Twenty-two patients with low-grade MALT lymphoma had ulcers (n = 11), fold thickening (n = 7), mucosal nodularity (n = 7), masses (n = 6), or prominent areae gastricae (n = 4) at UGI examination. Six patients with high-grade MALT lymphoma had masses (n = 4), fold thickening (n = 3), ulcers (n = 1), or mucosal nodularity (n = 1) at UGI examination. These findings were similar to those in gastric carcinoma or gastritis. Differentiation of low-grade MALT lymphoma from gastritis or gastric carcinoma was more difficult than differentiation of high-grade MALT lymphoma. Lesions of MALT lymphoma associated with H pylori gastritis were diffuse or multiple in 65% of cases; however, lesions of MALT lymphoma without proved H pylori gastritis were focal or solitary in 80% of cases. Therefore, multiplicity of lesions in MALT lymphoma was closely associated with H pylori infection.

MALT Lymphomas

This review addresses the biology and the treatment of lymphomas arising from mucosa-associated lymphoid tissue (MALT). This entity, first described in 1983, represents about 8% of all non-Hodgkin's lymphomas and was recently re-classified as "extranodal marginal zone lymphomas of MALT-type." The term marginal zone lymphoma (MZL) encompasses the three closely related lymphoma subtypes of nodal, primary splenic and extranodal lymphomas of MALT type: the latter represent the vast majority of MZL. These lymphomas arise at different anatomic sites, are composed of mature B-cells lacking expression of CD5 and CD10, often present with overlapping morphologic features, but typically quite distinct clinical behaviors. Only very recently cytogenetic/molecular genetic observations have underlined the distinctiveness of these three lymphoid neoplasms, which in both the R.E.A.L. and WHO-classifications are included in the general term of MZL. MALT lymphomas arise in numerous extranodal sites, but gastric MALT lymphoma is the most common and best studied and is, therefore, the paradigm for the group as a whole. Dr. Isaacson describes the principal histological features of these lymphomas, including criteria to distinguish this entity from other small B-cell lymphomas. Several lines of evidence suggest that gastric lymphoma arises from MALT acquired as the result of aH. pyloriinfection. However, at least 1/3 of cases do not respond to eradication ofH. pylori. Very recent data suggest that both t(11;18) (q21;q21) and bcl10 nuclear expression are associated with failure to respond to this treatment. Dr. Gascoyne discusses the biologic function of proteins deregulated through the different translocations, which play a role in pathogenesis of MALT lymphomas, emphasizing particularly their influence in disrupting the apoptotic pathway. Dr. Zucca reviews findings suggesting that MALT lymphoma is an antigen driven neoplasm. He also presents specific guidelines for treatment of gastric lymphomas trying to shed some light on the amazingly inconsistent and confusing data in the literature. Taking advantage on the more than 300 non-gastric MALT lymphomas collected by the International Extranodal Lymphoma Study Group (ILESG), Dr. Cavalli compares gastric lymphomas with those arising in many other sites. Overall, the data presented in this session will underline the fact, that MALT lymphomas are characterized by some unique biological properties.

Clone-specific PCR reveals wide dissemination of gastric MALT lymphoma to the gastric mucosa

The development of low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma is closely associated with Helicobacter pylori infection. Despite its indolent clinical course and prolonged localization to the site of origin, the lymphoma frequently presents with multifocal lesions. However, the true extent of tumour involvement in the gastric mucosa is unclear, since reactive appearing lymphocytic infiltrates are always present and could contain tumour cells that are not readily identifiable on cytological grounds. Gastrectomy specimens of four MALT lymphoma cases were studied by microdissection and clone-specific polymerase chain reaction (CS-PCR) and of a further case with t(1;14)(p22;q32) by immunohistochemistry for BCL10 protein, which acted as a tumour marker for tumour cells carrying the translocation. CS-PCR revealed that tumour cells were commonly present in histologically non-lymphomatous lymphocytic infiltrates microdissected from areas well separated from tumour lesions. Tumour cells were also frequently found in infiltrates microdissected from the resection margins. These findings were reinforced by direct identification of tumour cells, as recognized by strong BCL10 nuclear staining, in non-lymphomatous lymphocytic infiltrates in the case with t(1;14)(p22;q32). The results show that gastric MALT lymphoma disseminates widely within the gastric mucosa without necessarily forming diagnostic lesions.

Low-grade MALT lymphoma of the stomach: a review of treatment options

PURPOSE

Low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach (MLS) is often associated with the presence of Helicobacter pylori (H. pylori) bacteria. Eradication of the infection with antibiotic therapy may result in regression of the lymphoma. But when antibiotic treatment fails to reverse the malignant process or if H. pylori is absent, other treatment options should be considered. Because MLS is often confined to the stomach and regional lymph nodes, it is potentially curable with local therapy. Endoscopy and improved imaging, with endoscopic ultrasound (EUS) and computerized tomography (CT), have reduced the prior dependence on surgery for diagnosis and staging of gastric lymphomas.

METHODS AND RESULTS

This review details the advances in the diagnosis, classification, and imaging of MLS. We also describe the experience that supports the use of radiation therapy as the preferred treatment of MLS in patients who have not responded to antibiotic therapy or have not had evidence for H. pylori infection.

CONCLUSIONS

Radiation therapy for MLS is not only effective and safe, but offers the significant advantage of low morbidity and gastric function preservation.

Mucosa-associated lymphoid tissue and other gastrointestinal lymphomas

The gastrointestinal tract is the most common site for extranodal lymphomas. The most common, and consequently the most studied, gastrointestinal lymphoma is gastric mucosa-associated lymphoid tissue lymphoma, which is a paradigm for all gastrointestinal lymphomas. Recent advances in oncogenesis, genetics, and immunology have all yielded important discoveries that enhance our understanding of this lymphoma. The implications of these new advances are beginning to translate into changes in therapeutic approach.

Mucosa-associated lymphoid tissue lymphomas

Mucosa-associated lymphoid tissue (MALT) lymphoma has attracted attention because its concept has amalgamated the study of etiology and pathogenesis in an intriguing group of lymphomas. MALT lymphomas are a B-cell malignancy with characteristic lymphoepithelial lesions; cells are CD20-positive and CD5- and CD10-negative. The molecular changes observed include trisomy 3, t(11;18), and t(1;14) translocations. They commonly occur in the stomach, orbit, salivary glands, and thyroid. Localized disease is present in 60% to 70% of patients. Involvement of multiple extranodal sites has been observed at presentation or during the course of disease. Lymphocyte homing has been implicated in gastrointestinal MALT and may be involved in other MALT lymphomas. Local therapy, either through surgery or radiotherapy, is curative in a high proportion of patients. MALT lymphomas respond to chemotherapy, but there is no evidence that cure can be achieved, although prolonged survival is common. Long-term follow-up is essential for study of the outcomes in this disease.