HELICOBACTER PYLORI AND t(11;18)(q21;q21) TRANSLOCATION IN GASTRIC MALT LYMPHOMA / Helicobacter pylori e presença de translocação t(11;18)(q21;q21) em pacientes portadores de linfoma MALT gástrico

Context Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is clearly associated with Helicobacter pylori gastritis and can be cured with anti- H pylori therapy alone. The presence of t(11;18)(q21;q21) translocation is thought to predict a lower response rate to anti- H pylori treatment. Objectives To study the presence of t(11;18)(q21;q21) genetic translocation and its clinical impact in low-grade gastric MALT lymphoma Brazilian patients. Methods A consecutive series of eight patients with gastric MALT lymphoma were submitted to gastroscopy, endoscopic ultrasound, histopathological examination, H pylori search and RT-PCR-based methodology. All patients received anti-H pylori treatment. Eradicated patients were followed-up every 3-6 months for 2 years. Results Eight patients were studied. All patients had tumor involvement restricted to the mucosa or submucosa and seven patients had low-grade gastric MALT lymphoma. All infected patients achieved H pylori eradication. Histological tumor regression was observed in 5/7 (71%) of the low-grade gastric MALT lymphoma patients. The presence of t(11;18)(q21;q21) translocation was found in 4 (57%) of these patients; among them only two had histological tumor regression following H pylori eradication. Conclusions RT-PCR is a feasible and efficient method to detect t(11;18)(q21;q21) translocation, being carried out in routine molecular biology laboratories. The early detection of such translocation can be very helpful for better targeting the therapy to be applied to gastric MALT lymphoma patients. .

Contexto A patogênese do linfoma MALT (tecido linfoide associado à mucosa) gástrico, também conhecido como linfoma de zona marginal de células B, está claramente associada à gastrite por infecção pelo Helicobacter pylori e, a maioria desses tumores pode ser curada apenas com a erradicação da bactéria. A presença da translocação t(11;18)(q21;q21) tem sido identificada como a anomalia citogenética mais comum do linfoma MALT gástrico e sua presença pode prever uma menor taxa de resposta ao tratamento anti-H pylori. Objetivos Estudo da translocação genética t(11;18)(q21;q21) e seu impacto na evolução clínica de pacientes portadores de linfoma MALT gástrico de baixo grau. Métodos Uma série consecutiva de oito pacientes com linfoma MALT gástrico foi submetida à endoscopia digestiva, ultra-sonografia endoscópica, exame histopatológico, pesquisa do H pylori e metodologia rotineira de transcrição reversa seguida de reação em cadeia da polimerase (RT-PCR) utilizando primers específicos para API2-MALT1. Todos os pacientes receberam tratamento anti-H pylori e retratamento, quando necessário. Após a erradicação, exames endoscópicos foram realizados a cada 3-6 meses durante 2 anos para acompanhamento da evolução do tumor. Resultados Foram estudados oito pacientes (seis mulheres, idade média: 57 anos). Todos apresentavam à ecoendoscopia envolvimento tumoral restrito à mucosa ou submucosa com aparência endoscópica variável. A histologia mostrou que sete pacientes tinham linfoma MALT gástrico de baixo grau e um de alto grau. A erradicação do H pylori foi obtida em todos os pacientes, embora a bactéria não tenha sido identificada em um deles. Foi observada regressão histológica ...

Infecciones por bacterias poco comunes y oncogénesis bacteriana / [Infections due to unusual bacteria and bacterial oncogenesis].

The recovery of an unusual organism in the clinical microbiology laboratory may be an indicator of an immunological abnormality in the patient. For instance, an important relationship between Clostridium septicum and colon carcinoma as well as between leukemia or lymphoma with species frequently considered contaminants (Bacillus spp., Corynebacterium spp.) or others rarely isolated from different contexts (Capnocytophaga spp.) were described. Some bacteria are almost exclusively isolated from AIDS patients (Rhodococcus equi). Campylobacter spp., Aeromonas spp., group G and mitis group streptococci were more frequently isolated in individuals suffering from any type of cancer than in other patients. Furthermore, some other bacteria can be considered markers of an undetected cancer that can be found mostly in neutropenic patients rather than in immunologically normal individuals. Possible mechanisms of bacterial oncogenesis include a modification of the inflammatory response, antigen-derived lymphoproliferation, and induction of hormones that increase epithelial cell proliferation. Typical examples of the above are: gastric adenocarcinoma induced by Helicobacter pylori, the association between group bovis bacteremia and colon carcinoma and the mucosa-associated lymphoid tissue (MALT) related to Helicobacter species (gastric MALT) and Chlamydophila spp. (ocular MALT). Isolation of any of these pathogens should require a thorough search for possible malignant diseases.

Chronic gastritis and helicobacterpylori: a histopathological study of gastric mucosal biopsies

The aim of this study was to observe the histological features of chronic gastritis and associated effects due to Helicobacter pylori infection in 176 randomly selected antral biopsy specimens of chronic gastritis cases. The specimens were reviewed for the presence or absence of H.pylori. The activity [neutrophilic infiltration] of gastritis and the presence or absence of mucosa-associated lymphoid tissue [MALT] were also noted. Chi-square test [Pearson value] was used to analyze categorical variables. H.pylori was detected in 110 [62.5%] cases of chronic gastritis. There was a significant association between H.pylori infection and activity of chronic gastritis [p=0.002]. Lymphoid aggregates were significantly more frequently noted in H pylori-positive patients [68.2%] vs. H.pylori negative group [47%], [p=0.005]. It is concluded that H.pylori is significantly associated with active chronic gastritis and with formation of mucosa-associated lymphoid tissue [MALT], which may develop into gastric lymphoma [MALT type]

Elevada prevalencia de infección por helicobacter pylori en el linfoma gástrico de tipo MALT: [revisión] / Prevalence of helicobacter pylori infection in gastric MALT lymphoma: [review]

Objetivo: Realizar una revisión sistemática de los estudios que evalúan la prevalencia de Helicobacter pylori en los pacientes con linfoma MALT, así como analizar los factores de los que depende. Métodos: Se efectuó una búsqueda bibliográfica en Pubmed y se seleccionaron los artículos en los que se estudiaba la prevalencia de H. pylori en pacientes con linfoma MALT. Resultados: Se identificaron 38 estudios que incluían un total de 1 844 pacientes. La prevalencia media global de infección por H. pylori fue del 79%. En pacientes en los que se utilizaron dos o más métodos para el diagnóstico de H. pylori la prevalencia fue del 85%, frente al 77% cuando se empleó un método diagnóstico (p < 0.0001). La prevalencia de H. pylori en pacientes diagnosticados mediante histología fue del 75% frente al 85% cuando se utilizó serología (p < 0.0001). La prevalencia de H. pylori en los linfomas MALT de alto grado fue del 60%, frente al 79% en los de bajo grado (p < 0.0001). Se detectó la infección en el 74% de los linfomas MALT confinados a la submucosa, y sólo en el 44% de aquellos que sobrepasaban la submucosa (p < 0.0001). Conclusiones: La prevalencia de la infección por H. pylori en pacientes con linfoma MALT gástrico parece depender del número y tipo de técnicas diagnósticas utilizadas para detectar la infección, del grado histológico y de la profundidad de la invasión tumoral. Si se utilizan los métodos diagnósticos adecuados y si se consideran únicamente los linfomas de bajo grado la prevalencia de infección por H. pylori es muy elevada, cercana al 90%.

High-grade Hepatic Mucosa-associated Lymphoid Tissue (MALT) Lymphoma Probably Transformed from the Low-grade Gastric MALT Lymphoma

The Mucosa-associated lymphoid tissue (MALT) lymphoma, which was first described in 1983, is known to be caused by chronic Helicobacter pylori (HP) infection, which triggers lymphoid infiltration and formation of organized lymphoid tissue. In approximately two thirds of cases of MALT, the lymphoma has been observed to regress after treatment of H. pylori infection; this provides strong evidence of a causative role of HP in the etiology of MALT. We report a case of a 67-year-old female patient with a high-grade MALT lymphoma of the liver; this occurred six years after complete remission of a low-grade gastric MALT lymphoma and after complete eradication of H. pylori. there was no recurrence of the previous low-grade gastric MALT lymphoma. Based on radiological and pathologic findings, the high-grade MALT was considered to result from transformation of the low-grade gastric MALT lymphoma.

Helicobacter pylori and cagA gene detected by polymerase chain reaction in gastric biopsies: correlation with histological findings, proliferation and apoptosis

CONTEXTO E OBJETIVO: A virulência de Helicobacter pylori em doenças gastroduodenais está relacionada à presença de ilha de patogenicidade (cagPAI) que ocorre em algumas cepas. A infecção pelo cagPAI induz a secreção de IL-8, aumenta a proliferação epitelial, podendo ter um papel importante na carcinogênese. Nosso objetivo foi detectar HP e o gene cagA (marcador de cagPAI) pela técnica de PCR (polymerase chain reaction), correlacionando com os achados histológicos, de proliferação e apoptose. TIPO DE ESTUDO E LOCAL: Estudo retrospectivo, no Laboratório de Patologia Cirúrgica e Molecular do Hospital Sírio Libanês. MÉTODOS: DNA isolado de 164 biópsias gástricas foi submetido a PCR para detecção de HP. Os casos positivos foram submetidos a nova reação para identificação do gene cagA. Pela técnica de imunohistoquímica foi analisada a proliferação celular e, pela TUNEL, a apoptose. RESULTADOS: HP foi detectado em 67,7% dos pacientes. Houve correlação entre a presença do HP e o diagnóstico de gastrite moderada ou grave, úlcera e linfoma do tipo MALT. Houve correlação entre cagPAI+ e a doença gástrica grave, incluindo o câncer. O risco de úlcera, adenocarcinoma ou linfoma MALT para os portadores de cagA+ foi de 8,8. Infecção pelo cagPAI correlacionou-se com aumento na taxa de proliferação. O índice proliferação/apoptose foi significantemente maior para os pacientes cagPAI+. CONCLUSÕES: Uma desregulação do crescimento celular nos pacientes cagPAI+ foi demonstrada pela diferença do índice de proliferação, que acreditamos pode explicar o papel carcinogênico da bactéria.

Low-grade Mucosa-associated Lymphoid Tissue Lymphoma of Stomach / 대한소화기학회지

Stomach is the most common site of primary extranodal lymphoma. Mucosa-associated lymphoid tissue (MALT) lymphoma is a unique type of extranodal lymphoma which is associated with Helicobacter pylori (H. pylori). The development of low-grade MALT lymphoma of stomach is dependent on H. pylori. A transformed clone carrying the translocation t(11;18)(q21;q21) forms a MALT lymphoma, the growth of which is independent of H. pylori and will not respond to bacterial eradication. And inactivation of the tumor suppressor genes, p53 can lead to high-grade transformation. Endoscopic ultrasound (EUS) is essential to document the extent of disease and is superior to CT scan in the detection of spread to perigastric lymph nodes and follow-up EUS may determine the response to therapy and detect the relapse in early phase. Lesions that are confined to the mucosa or submucosa of gastric wall can be successfully treated with H. pylori eradication. Those low-grade MALT lymphomas that are not H. pylori positive or do not respond to antibiotic therapy can be treated with surgery, radiation, or chemotherapy. Follow-up is critical in all patients who have been treated with H. pylori eradication and consists of multiple endoscopic biopsies and EUS.

Helicobacter pylori: 20 años después / Helicobacter pylori: two decades later

Twenty years ago Helicobacter pylori was identified in the gastric content and this finding stimulated a multitude of studies and publications that changed drastically our knowledge of common gastric conditions such as peptic ulcer and gastric cancer. This progress has affected significantly our practice and has resulted in great benefits for our patients. The relationship of the bacteria to the pathogenesis of gastritis, peptic ulcer, gastric cancer and gastric lymphoma was firmly established. A large number of individuals are infected (an estimated half of the world's population) while only a minority suffers of the above mentioned conditions, so it became clear that certain strains of the bacteria, susceptibility of the host and environmental factors interplay in causing the damage. The diagnosis of the infection became a standard practice and therapy and prevention of these common conditions has been drastically modified. Eradication of the bacteria resulted in the cure of ulcers, in a dramatic decrease in the rate of its complications and in the ocurrence of gastric cancer. Better sanitary conditions are part of the solution. Also it is successful in the management of certain gastric lymphomas. The treatment however, is expensive and not free of side effects. Further research work is needed to facilitate the diagnosis and less expensive treatments should be available to eradicate Helicobacter pylori throughout the world.

Gastric malt lymphoma. A clinico-pathological study of 65 cases. Relationship to Helicobacter pylori

We report 65 cases of MALT gastric lymphomas. HP was looked for with Giemsa and Whartin Starry stains. Immunohistochemistry was done with PAP method. Anti-HP treatment was used in 9 cases. 38 were of low grade of malignancy, 23 were high grade, 4 were high grade with a low grads component. The mean age was 51.5 years, the sex ratio 1.5. Epigastric pain was the most frequent feature [87.7 percent of cases]. Endoscopically, low grade lymphomas presented as unique or multiple ulcerations [55.3 percent of cases] with antral localization [52.6 percent of cases]. 60 percent of our patients were stage IE, of which 61 percent had low grade lymphoma, 18 percent were at stage 112E, 10 percent at stage III and 10 percent at stage IV. From 23 operated patients, 29 percent had early lymphoma which was low grads malignant in 71.5 percent of cases, and 71 percent had lymphomas which were wi-dely spread beyond the submucosa. HP was found in 63 percent of cases. Histologic regression of two early lymphomas of low grade malignancy was achieved after HP eradication

Linfoma MALT gástrico em paciente jovem / Gastric lymphoma MALT in an young patient

É descrito um caso incomum de linfoma de tecido linfóide associado à mucosa (MALT) gástrico em paciente de 25 anos, que evoluiu com vários episódios de hematêmese, resultando em choque hipovolêmico, necrose tubular aguda e óbito. Embora o paciente tenha cursadocom gastrite, a pesquisa para Helicobacter pylori foi negativa. A descrição se justifica tanto pela evolução rápida da neoplasia, quanto pela faixa etária do paciente. Além disso, a descrição deste tipo de linfoma colabora no aumento da casuística documentada por exame necroscópico na literatura biomédica.

An uncommon case of the mucosa associated lymphoid tissue (MALT) gastric lymphoma is described in 25 year-old patient, that developed with several hematemesis episodes, resulting in hipovolemic shock, acute tubular necrosis and death. Although the patient had gastritis, the research for Helicobacter pylori in the stomach was negative. These paper is justified by the fast evolution of the neoplasm, and the patient's age group. In addition, the descrition of this lymphoma type collaborates in the increase of the casuistic documented by autopsies in the biomedical literature.

Helicobater pylori: revisão / Helicobater pylori: review

Os autores fazem a revisào da literatura sobre a infecção da mucosa gástrica pelo "Helicobater pylori" com ênfase sobre sua microbiologia, epidemiologia, relaçào com as doenças do estômago, diagnóstico e tratamento (au)

Helicobacter pylori associado a linfoma gástrico primário tipo MALT / Helicobacter pylori associated to primary gastric lymphoma type MALT

O trato gastrointestinal é o local mais comum de comprometimento por linfoma näo Hodgkin extranodal primário, sendo o linfoma gástrico primário o mais freqüente, correspondendo a 2/3 dos casos. Isaacson e Wright, em 1983, introduziram o conceito de tecido linfóide associado a mucosa (MALT), relatando que este tecido precede o aparecimento de linfomas de célula B tipo MALT no estômago. Este tecido linfóide é adquirido, provavelmente resultante da infecçäo por Helicobacter pylori na mucosa gástrica. No período de janeiro de 1983 a dezembro de 1994 foram realizados 22 diagnósticos de linfoma gástrico primário, no Serviço de Hematologia e Hemoterapia da Santa Casa de Säo Paulo. Após revisäo histológica foram encontrados 13 casos de linfoma tipo MALT, sendo que o H. pylori foi positivo em 92,3 por cento dos casos. Esse achado é importante, pois há estudos mostrando que em pacientes com linfoma gástrico primário de baixo grau, de célula B, tipo MALT, com H. pylori positivo, após a erradicaçäo do H. pylori houve regressäo do linfoma.