Gastric Mucosa-associated Lymphoid Tissue Lymphoma Research Articles

The Benefits of Non-Surgical Periodontal Treatment in Association with Gastric Eradication

Periodontitis is a chronic degenerative disease which is inflammatory and whose bacteriological aetiology interests the hard and soft tissues supporting the dental elements. A typical characteristic of periodontitis is its correlation with other branches of medicine since periodontal disease is often associated with several other illnesses or systemic conditions which exacerbate or predispose the course of the disease. Amongst the most frequent gastroduodenal diseases are those associated with Helicobacter pylori (Hp) infections such as acute gastritis, chronic atrophic gastritis, gastric atrophy, gastritis ulcers, dysplasia, duodenal ulcer, gastric cancer, gastric MALT-lymphoma. Transmission of the microorganism occurs through iatrogenic pathways (faecal-oral, oral-oral) and through food and water ingestion. From this the possible role of the oral cavity becomes evident as a means of transmitting the microorganism and as an extra-gastric reservoir of Hp which develops inside the oral plaque, the main aetiological agent of periodontal disease. Considering that in a patient affected with periodontal disease the oral cavity presents elevated indices of bacterial plaque in association with infrabony pockets one is brought to ask if it might represent a favourable habitat for Hp colonisation. Furthermore, another query that one might pose is whether the presence of Hp in the oral cavity might be the cause of relapse in gastric infections caused by Hp. Consequently, might non-surgical periodontal treatment, in association with an eradicating gastric therapy, foster decontamination of the microorganism in the oral cavity leading to a better prevention of relapse and re-infection of the gastric cavity? Could non-surgical periodontal treatment thus mean prevention of gastric diseases brought on by Helicobacter pylori? The objective of this study is therefore to evaluate the incidence of periodontal disease and oral Hp infection in patients affected by gastric Hpinfection and to determine the possible benefits of the association of non-surgical periodontal therapy with eradicating gastric therapy compared with treatment that involves just the eradicating gastric therapy in patients who are affected by periodontal disease and Hp infection.

A Case of Gastric Perforation after Complete Remission of Gastric MALT Lymphoma by Radiotherapy

A Case of Gastric Perforation after Complete Remission of Gastric MALT Lymphoma by Radiotherapy

<i>Helicobacter pylori</i>-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphoma Presenting with Melena as the Initial Symptom

<i>Helicobacter pylori</i>-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphoma Presenting with Melena as the Initial Symptom

Heterogeneity of clinical management of low-grade gastric lymphoma of mucosa-associated lymphoid tissue. An audit of 198 patients in Spain

IntroductionCure of Helicobacter pylori infection in patients with gastric lymphoma of mucosa-associated lymphoid tissue (MALT) leads to long-term clinical remission in the initial stages. As it is a rare disease, its management in clinical practice remains largely unknown and heterogeneity of care remains a concern.The aim was to audit the management and evolution of a large series of low-grade gastric MALT lymphomas from thirteen Spanish hospitals. Materials and methodsMulticentre retrospective study including data on the diagnosis and follow-up of patients with gastric low-grade MALT lymphoma from January 1998 to December 2013. Clinical, biological and pathological data were analyzed and survival curves were drawn. ResultsOne-hundred and ninety-eight patients were included. Helicobacter pylori was present in 132 (69%) patients and 103 (82%) in tumors confined to the stomach (stage EI) and was eradicated in 92% of patients. Chemotherapy was given in 90 (45%) patients and 43 (33%) with stage EI. Marked heterogeneity in the use of diagnostic methods and chemotherapy was observed. Five-year overall survival was 86% (89% in EI). Survival was similar in EI patients receiving aggressive treatment and in those receiving only antibiotics (p=0.577). DiscussionGastric MALT lymphoma has an excellent prognosis. We observed, however, a marked heterogeneity in the use of diagnostic methods or chemotherapy in early-stage patients.

267O - Treatment outcome for gastric mucosa-associated lymphoid tissue lymphoma with Helicobacter Pylori negative

BackgroundUnlike that for Helicobacter pylori (H.pylori)-positive gastric mucosa-associated lymphoid tissue (MALT) lymphoma, the management strategy for H.pylori-negative MALT lymphoma remains controversial. Therefore, the aim of the present study was to examine the success of each treatment option for H.pylori-negative gastric MALT lymphomas. MethodsBetween June 2000 and June 2017, a total of 89 H.pylori-negative gastric MALT lymphoma patients were enrolled retrospectively. H.pylori-positive status was defined by positive results for the biopsy urease test and histology. They had all been diagnosed by endoscopy and had a complete staging including CT-scan. Tumors that had resolved to complete remission score of GELA histologic grading system were considered treatment-responsive. ResultsSixty-two patients (69.7%) underwent H.pylori eradication therapy. After H.pylori eradication, ChR was achieved in 15 patients (24.2%) and pMRD in 13 (21.0%). he median time from H.pylori eradication to ChR or pMRD was 84 days. Fifteen patients took radiotherapy and six patients chose combination chemotherapy with or without rituximab as following, RCVP in 3, CVP in 1, and CHOP in 2. The all of them who took radiotherapy and chemotherapy achieved ChR. Median follow-up period was 45.4 months, lymphoma relapse was observed in nine patients (10.1%). Disease progression was observed in 3 of 33 non-responders. Probabilities of overall survival and event-free survival at 10 years were 98.5%, and 61.4%, respectively. ConclusionsA substantial proportion of patient with H.pylori-negative gastric MALT lymphoma remain antibiotic-responsive and can be cured using radiotherapy and chemotherapy. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Comparación de prevalencia de infección por Helicobacter pylori en pacientes con dispepsia entre dos instituciones de diferentes estratos socioeconómicos en el periodo 2017-2018

Helicobacter pylori (Hp) infection is associated with multiple digestive problems from gastroduodenal ulcers to gastric adenocarcinoma and/or MALT lymphoma. Peru is considered a place of high prevalence of Hp. In the world, significant differences have been described in the prevalence of Hp infection associated with the socioeconomic characteristics of the population. Objective: To compare the prevalence of Hp infection in dyspeptic patients between 2 institutional centers of different socio-economic strata during 2017-2018. Materials and methods: A sample of 633 patients with dyspepsia was collected retrospectively and randomly, without previous endoscopic study, or a history of Hp eradication therapy that came to the gastroenterology services of the Hospital Cayetano Heredia (HCH) in San Martin de Porres, and of the Anglo American Clinic (CAA) in San Isidro, during the period of June 2017 - July 2018 (CAA: 300 and HCH: 333). Proceeding then to review the clinical history, endoscopy report and pathological anatomy of each of them, for further statistical analysis using the SPSS program. Results: A prevalence of Hp was found in the HCH of 54.1%, while in the CAA it was only 29.3% (p<0.05), this relationship being maintained in the different age groups. Likewise, the prevalence of intestinal metaplasia (MI) in the total of patients with dyspepsia in the HCH was 33.9% (MI + in Hp + was 34.4%) and in the CAA the presence of MI without considering the Hp status was only 6.7% (MI + in HP + was 6.8%) (p<0.05). Finally, the presence of gastric atrophy in the HCH was 26.7% and in the CAA it was 1.3% (p<0.05). Conclusion: There is a clear relationship between the low socioeconomic stratum and the presence of Hp, gastric atrophy and intestinal metaplasia (the latter relationship remaining independent of Hp status).

Th17 Cells in Helicobacter pylori Infection: a Dichotomy of Help and Harm

Helicobacter pylori is a Gram-negative bacterium that infects the gastric epithelia of its human host. Everyone who is colonized with these pathogenic bacteria can develop gastric inflammation, termed gastritis. Additionally, a small proportion of colonized people develop more adverse outcomes, including gastric ulcer disease, gastric adenocarcinoma, or gastric mucosa-associated lymphoid tissue lymphoma. The development of these adverse outcomes is dependent on the establishment of a chronic inflammatory response. The development and control of this chronic inflammatory response are significantly impacted by CD4+ T helper cell activity. Noteworthy, T helper 17 (Th17) cells, a proinflammatory subset of CD4+ T cells, produce several proinflammatory cytokines that activate innate immune cell antimicrobial activity, drive a pathogenic immune response, regulate B cell responses, and participate in wound healing. Therefore, this review was written to take an intricate look at the involvement of Th17 cells and their affiliated cytokines (interleukin-17A [IL-17A], IL-17F, IL-21, IL-22, and IL-26) in regulating the immune response to H. pylori colonization and carcinogenesis.

Are Histopathological Changes of H. pylori Infection in Young Dyspeptic Patients Necessitate Endoscopy?

BACKGROUND:Helicobacter pylori is an important gastrointestinal infective bacteria with many serious complications including gastric erosions and ulceration, duodenal ulcer, gastric carcinoma and MALT gastric lymphoma. The gastric biopsy is commonly performed in H. pylori-positive dyspeptic individuals, and many previous researchers studied the histopathological features of infected gastric biopsies however little previous studies focused on the histopathological findings in young population in comparison to the older one.AIM:To make a focus on the histopathological effects of H. pylori infection in young patients compared with the older one and predicts the need for endoscopy in this population, also to estimates the prevalence of infection in Iraqi patients.MATERIAL AND METHODS:the sample for this study is 180 patients in total, they attended Marjan medical city in Iraq for dyspepsia of more than 3 months and prepared for OGD. Patients asked for their permission to do immunological tests for H. pylori. Both serology for H. pylori antibodies and stool for antigen tests are used, and the case is included in the study only if both tests were positive, after OGD, the gastric biopsies are processed and examined histopathologically.RESULTS:Normal gastric biopsy is the most common histopathological finding in young (< 25 years) patients (75%) while chronic atrophic gastritis is the most common one in patients > 25 years age (57%). The prevalence of Helicobacter pylori infection in dyspeptic patients was 73.3%, the correlation between infection and sex was insignificant (p-value 0.06), and no significant correlation between infection and age (p-value 0.07) was concluded.CONCLUSION:H. pylori-related histopathological changes of gastric mucosa in young (< 25 years) are commonly mild and does not necessitate endoscopy at this age unless there are alarming signs.

1081P - Efficacy of salvage therapy in the treatment of Helicobacter pylori-positive gastric low-grade mucosa-associated lymphoid tissue lymphoma

BackgroundHelicobacter pylori (H.pylori) infection has a critical role in the pathogenesis of gastric mucosa-associated lymphoid tissue (MALT) lymphoma and its eradication can lead to tumor regression. However, in patients who do not achieve a lymphoma regression or relapse following antibiotic therapy, outcome of the patients are scarce. We evaluated the long-term outcome of the patients who received salvage therapy with relapsed or refractory gastric MALT lymphoma. MethodsBetween June 2000 and June 2017, a total of 29H.pylori-positive gastric MALT lymphoma patients who received frontline H.pylori eradication were included in this study. H.pylori-positive status was defined by positive results for the biopsy urease test and histology. They had all been diagnosed by endoscopy and had a complete staging including CT-scan. Patients received standard triple therapy for eradication of H.pylori and after treatment were sequentially followed-up with endoscopies performed to evaluate the response. Tumors that had resolved to complete remission (CR) score of GELA histologic grading system were considered treatment-responsive. ResultsDuring the follow-up periods 16 patients were refractory, nine had probable minimal residual disease and four relapsed after the first-line antibiotics. Of these 29 patients, transformation into high-grade B-cell lymphoma did not occur. Among the non-responder and relapsed patients, three patients were subjected to a watch and wait, while 26 patients underwent second-line treatment including radiotherapy (n=20), chemotherapy (n=5), chemotherapy plus sequential radiotherapy (n=1). Of the 20 patients treated with radiotherapy, the median dose to stomach was 3060 cGy (range, 1620-5000 cGy). After radiotherapy a CR was achieved in 20 patients (100%). Among six patients who received chemotherapy, a CR was achieved in five patients and no change was in one. That patient was achieved CR after radiotherapy. Probabilities of freedom from treatment failure and overall survival after 10 years were 100% and 83%. ConclusionsOutcome of patients with first-line H.pylori eradication failure followed by delayed chemotherapy and/or radiotherapy on indication was excellent. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

1071PD - Treatment outcome for Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma

BackgroundUnlike that for Helicobacter pylori (H.pylori)-positive gastric mucosa-associated lymphoid tissue (MALT) lymphoma, the management strategy for H.pylori-negative MALT lymphoma remains controversial. Therefore, the aim of the present study was to examine the success of each treatment option for H.pylori-negative gastric MALT lymphomas. MethodsBetween June 2000 and June 2017, a total of 89 H.pylori-negative gastric MALT lymphoma patients were enrolled retrospectively. H.pylori-positive status was defined by positive results for the biopsy urease test and histology. They had all been diagnosed by endoscopy and had a complete staging including CT scan. Tumors that had resolved to complete remission score of the GELA histologic grading system were considered treatment responsive. ResultsSixty-two patients (69.7%) underwent H.pylori eradication therapy. After H.pylori eradication, complete hematologic resonse (ChR) was achieved in 15 patients (24.2%) and pathological minimum residual disease (pMRD) in 13 (21.0%). The median time from H.pylori eradication to ChR or pMRD was 84 days. Fifteen patients received radiotherapy and all of them achieved ChR. Six patients chose combination chemotherapy with or without rituximab as follows, RCVP in 3, CVP in 1, and CHOP in 2. Two patients took subtotal gastrectomy followed by adjuvant CHOP treatment. All of them achieved ChR after chemotherapy. The clinical course after second-line treatment applied to 33 non-responders and six responders with relapse and the second-line treatments resulted in ChR in 30 patients, pMRD in one, and rRD in two patients. The rate of the ChR induction by each treatment was 100% by radiotherapy, 50% by chemotherapy. Median follow-up period was 45.4 months, lymphoma relapse was observed in nine patients (10.1%). Six patients were treated by either chemotherapy (n=2) or radiotherapy (n=3). Disease progression was observed in 3 of 33 non-responders. Only one patient showed transformation into diffuse large B-cell lymphoma. Probabilities of overall survival and event-free survival at 10 years were 98.5%, and 61.4%, respectively. ConclusionsA substantial proportion of patients with H.pylori-negative gastric MALT lymphoma remain antibiotic-responsive and can be cured using radiotherapy and chemotherapy. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

2707 Gastric Mucosa-Associated Lymphoid Tissue Lymophoma Treated by Endoscopic Mucosal Resection

INTRODUCTION: Primary low-grade gastric Mucosa-associated lymphoid tissue (MALT) lymphoma is a distinctive type of B-cell lymphoma. Endoscopic appearances of low-grade gastric MALT lymphoma are quite varied and polypoid or subepithelial type (exophytic) is rare. Here, we reported the case of H. pylori negative gastric MALToma presenting as an exophytic subepithelial tumor, diagnosing and treating by endoscopic mucosal resection (EMR). CASE DESCRIPTION/METHODS: A 53-year-old man was referred to our hospital because of a large subepithelial tumor of the stomach, which was incidentally found on an endoscopy for a routine checkup in outside hospital. Initial outside endoscopic biopsy was a simple chronic gastritis. Physical examination and laboratory results were unremarkable. On endoscopic examination, a 2.0 cm sized round and hard exophytic subepithelial tumor was seen on the great curvature side of high body of the stomach. The tumor showed a well-demarcated smooth border without any erosion and ulceration. An abdominal pelvic CT demonstrated an enhancing subepithelial tumor without regional lymphadenopathy, such as gastrointestinal stromal tumor. EUS showed a hypoechoic and heterogeneous mass in the 2nd and 3rd layer with ill-defined internal margin. EMR was done for both the definite diagnosis and the treatment without complications because the tumor had a semipedunculated morphology. Results of a histopathologic examination of the resected tumor showed diffuse lymphocytic proliferation in the submucosa mimicking a subepithelial tumor with lymphoepithelial lesions. Dense lymphocytic infiltration composed of mainly B cells forming vague follicular colonization. Immunohistochemical stain of cytokeratin also showed presence of lymphoepithelial lesions. The Ki-67 was positive in 7%. Histologically, no H. pylori was observed in the luminal side. Finally, the patient was diagnosed as a H. pylori–negative extranodal marginal zone B-cell lymphoma (MALToma) (stage EI1). No additional treatment such as chemotherapy or radiation was performed. The follow-up endoscopic examination showed no recurrence until 2 years after EMR. DISCUSSION: We suggest that EMR may be an alternative treatment modality in the diagnosis and the treatment of gastric MALT lymphoma in cases of submucosal or polypoid morphology type, especially when H. pylori is negative. Further study in terms of feasibility, efficacy, and long-term safety of EMR as a curative treatment would be warranted.

3229 Helicobacter pylori-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphomas: A Challenge in Treatment Options

INTRODUCTION: Primary gastric lymphoma is a rare entity of which the specific variant, mucosa-associated lymphoid tissue (MALT) lymphomas may be the best recognized given its association with Helicobacter pylori (H. pylori) infection. It has been thought that repetitive immune stimulation from underlying infection is influential in the pathogenesis of this tumor. However up to 10% of gastric MALT lymphomas are diagnosed without a concomitant H. pylori infection. The pathogenesis and management of H. pylori-negative gastric MALT lymphomas remains uncertain. CASE DESCRIPTION/METHODS: 65 year old woman with Celiac disease and GERD presented with worsening severe reflux and epigastric pain. She underwent EGD which revealed multiple superficial ulcers in the cardia with notable nodularity, ulceration, and friability. Cold forceps biopsies of the abnormal mucosa demonstrated diffuse atypical small B-Cell lymphoid infiltrate with features compatible with low grade MALT lymphoma. Of note, immunostain for H. Pylori was negative. Subsequent H. pylori stool antigen assay as well H. pylori IgG, IgM, and IgA were all negative. Given her negative antibodies indicating she truly had no exposure to H. Pylori, the patient has been referred to oncology for multidisciplinary management. DISCUSSION: This case of early stage gastric MALT lymphoma without evidence of active H. pylori infection elucidates that there is limited literature for the management for these patients. Studies have suggested that H. pylori eradication therapy can be efficacious for a proportion of H. pylori-negative gastric MALT lymphomas, possibly due to a false negative detection by biopsy. Local radiation therapy with curative intent and single agent rituximab therapy rather than H. pylori eradication have also been explored as alternate options. The data stems from retrospective studies and single agent prospective trials. Thus, there may be a role for future research directly comparing treatment strategies for optimal management of this clinical entity.

Atypical Lymphoid Proliferations and Clonality in Helicobacter-associated Inflammatory Infiltrates in Children.

Helicobacter infection is considered the major predisposing factor for gastric mucosa-associated lymphoid tissue (MALT) lymphoma with initial infection likely occurring in childhood. Primary gastric MALT lymphoma most commonly occurs in patients older than 50 years which is attributed to the lengthy chronic infection time required before the development of MALT lymphoma. Our study analyzes the histologic features and presence of immunoglobulin heavy chain (IGH) clonality in Helicobacter-associated chronic gastritis (62 cases) and Helicobacter-negative chronic gastritis (17 cases) biopsies within the pediatric population, diagnosed between 1996 and 2018. Helicobacter-associated gastritis was more likely to show active inflammation (P=0.01), with no significant difference in number of germinal centers or the strength, linear property, or depth of the inflammatory infiltrate. In total, 47% (29/62) of the Helicobacter-associated cases had at least 1 lymphoepithelial lesion, equivocal or definitive (a modified Wotherspoon score of 3 to 5), compared with 24% (4/17) of the Helicobacter-negative cases (P=0.5). All cases with lymphoepithelial lesions were assessed for IGH clonality, showing the presence of monoclonality in 27% (8/30) of evaluable cases. None of our patients were diagnosed with gastric lymphoma within available follow-up data. Although 4% of our cases could be considered MALT lymphoma in an adult patient based on prominent lymphoepithelial lesions and IGH monoclonality, caution is advised when diagnosing lymphoma in the pediatric population given the good prognosis of Helicobacter-associated gastritis in this age group. It is unclear if these monoclonal lymphoid proliferations require close follow-up.

1984 Helicobacter pylori-Negative MALT Lymphoma Presenting as Massive Recurrent Gastrointestinal Hemorrhage

INTRODUCTION: Extranodal marginal zone lymphoma or low-grade B cell lymphoma of mucosa-associated lymphoid tissue (MALT), an uncommon type of non-Hodgkin lymphoma (NHL), accounts for 5–10% of NHL in the US (18.3 cases per 1 million person-years1). It usually presents as gastro-esophageal reflux, nausea, anorexia, weight loss or occult GI bleeding2. Massive GI bleeding is unusual and rare. CASE DESCRIPTION/METHODS: Here we present a 68-year-old woman who presented with weakness and syncope after large volume hematemesis. Physical exam showed tachycardia, hypotension and conjunctival pallor. Her hemoglobin and hematocrit on admission were 8.5 g/dL and 25.6 %. She was managed with IV fluids, packed RBC transfusion and Pantoprazole and Octreotide infusions. An EGD within 24 hours showed erythematous, friable, spontaneously oozing mucosa with neovascularization in gastric fundus which was treated with bipolar cautery. A biopsy was not obtained due to recent bleeding. She was discharged on oral Pantoprazole. Two days later she was readmitted due to severe recurrent hematemesis with similar findings on repeat EGD. Bleeding was controlled with APC and biopsies were obtained from the gastric fundus. Due to the recurrent bleeding, an angiogram was performed. Active bleeding could not be seen. Prophylactically, left gastric artery was embolized. Biopsies revealed low-grade B cell MALT lymphoma with negative H.pylori. She was treated with 20 fractions of radiotherapy with the intention to cure. She did not experience further episodes of bleeding and has remained in remission since. DISCUSSION: Studies show the indolent nature of GI MALT lymphoma3, but our case illustrates the life-threatening presentation of a rare low-grade B cell MALT lymphoma as massive and recurrent hematemesis with negative underlying H.pylori infection or autoimmune process45. H.pylori positive localized MALT lymphoma is treated with the eradication of infection. H pylori negative, localized and recurrent disease is treated with radiotherapy6. Chemotherapy and/or immunotherapy is given when patients fail to respond to radiotherapy or develop metastasis. Long term endoscopic and laboratory follow up is needed as gastric MALT lymphoma is associated with a significant risk of gastric adenocarcinoma8 and increased incidence of gastric cancer and residual NHL. Our case emphasizes the importance of early diagnosis and timely intensive radiotherapy of a localized but aggressive gastric MALT lymphoma which induced remission and cessation of GI bleeding.

2669 Mucosa-Associated Lymphoid Tissue Lymphoma: Crossing the Borders!

INTRODUCTION: Mucosa-associated lymphoid tissue (MALT) lymphoma or MALTomas are responsible for half of the primary gastric lymphomas and up to 8% of B-cell lymphomas. It mostly affects patients in their 5th or 6th decade of life. MALT lymphoma is well known to remain localized in the stomach and to follow a benign course. Despite that gastric MALToma is well defined in the literature, it is rather uncommon to present as a peri-pancreatic mass. Herein, we present the case of a patient with an incidental peri-pancreatic mass diagnosed as an aggressive form of MALT lymphoma. CASE DESCRIPTION/METHODS: A 76-year-old male with hypertension presented to the gastroenterology clinic for the evaluation of peri-pancreatic mass incidentally found during computed tomography (CT) scan performed for renal colic. Physical examination was remarkable for an epigastric fullness with no tenderness. Laboratory tests were remarkable for iron deficiency anemia. CT showed a 7 cm ill-defined soft tissue mass within the pancreaticoduodenal groove abutting the pancreatic head and encasing the gastroduodenal artery suspicious for a pancreatic neoplasm (Figure 1). Endoscopic ultrasound (EUS) showed a hypoechoic heterogeneous mass arising from the gastric wall in close proximity to the pancreas (Figure 2). EUS-guided biopsies were consistent with extra-nodal marginal zone lymphoma of MALT (Figure 3). Gastric biopsies confirmed the presence of MALToma and revealed positive Helicobacter Pylori (HP) infection. Staging workup confirmed extensive bone marrow as well as para-aortic, mediastinal and paratracheal lymph node involvement. The patient received curative HP treatment and was started on bendamustine and rituximab. DISCUSSION: The stomach is the most commonly affected organ by MALT lymphoma. Helicobacter Pylori is a major precursor for the development of gastric MALT lymphoma as up to 90% of affected patients show H.Pylori on stomach biopsies. Chronic HP infection leads to lymphoid tissue proliferation within the stomach and progression towards lymphoma. In this setting, the course is usually indolent with the disease usually confined to the stomach but aggressive tumor behavior has been reported. HP antibiotic eradication remains the first line therapy for early-stage HP positive gastric MALT lymphoma. In other instances, a patient-tailored approach is recommended based on the stage, involved site, HP status and clinical characteristics. Therapeutic options include radiation therapy, chemotherapy and surgery accordingly.

2691 Quadruple Therapy: A Cure for Gastric High Grade B-Cell Lymphoma?

INTRODUCTION: H. pylori contributes to approximately 75 % of stomach cancers internationally. Gastric MALT lymphoma is a rare disease with an incidence of 0.38 per 100,000 people in the United States of America (USA). The majority of gastric MALT lymphoma cases are cured with H pylori eradication therapy while chemotherapy is the mainstay of treatment for gastric diffuse large B-cell lymphoma (DLBCL). Gastric high grade DLBCL is rare and there is limited data in which treatment with H pylori eradication can attain complete remission. We present a case of a woman with DLBCL and was treated for H pylori and attained complete remission. CASE DESCRIPTION/METHODS: A 59 year old woman presented to our clinic for evaluation of epigastric pain for 2 months. A trial of Prior proton pump inhibitor (PPI) treatment did not improve her pain. Abdominal CT imaging was significant only for diverticulosis. Esophagogastroduodenoscopy (EGD) showed a 25 mm non-bleeding cratered gastric ulcer with pigmented material at the incisura of the stomach. Incisiural biopsies revealed high grade B cell lymphoma and antral/body biopsies showed H pylori. PET CT imaging showed diffuse fluorodeoxyglucose uptake along the lesser curvature of the stomach corresponding to the known area of lymphoma. There was no evidence of metastatic disease. The patient declined chemotherapy due to fear of associated side effects. Instead, she was given H pylori quadruple therapy with a 14 day course of Pantoprazole, Bismuth subsalicylate, Metronidazole, and Tetracycline. Repeat EGD with endoscopic ultrasound at 1 and 4 months later were unremarkable and biopsies at the site of the healed ulcer were negative for neoplasia. To date, she remains asymptomatic. DISCUSSION: To date, there is no established standard management strategy for primary gastric lymphoma. Major guidelines recommend chemotherapy as the initial treatment for DLBCL. The efficacy of HP eradication for gastric pure DLBCL has mostly remained unknown, with limited data available. Despite histological remission, lymphoma recurrence is possible. Given the limited data available, long term, careful follow-up should be done for all patients if they are treated with antibiotics for DLBCL.

1082P - Mutational analysis of extranodal marginal zone lymphoma using next generation sequencing

BackgroundExtranodal marginal zone lymphoma is a type of low-grade B-cell lymphoma and may be classified as mucosal-associated lymphoid tissue (MALT) lymphoma. MALT lymphoma is most common in stomach in Korea. The etiologic factors are inflammation caused by chronic infection, autoimmune disease and genetic variation. Identifying various somatic mutations is an essential process in precision medicine, where high throughput sequencing is used to accurately detect genetic changes. Nucleotide sequencing techniques are basically based on the Sanger method, but recently second generation or next generation sequencing (NGS) that can sequence millions or billions of DNA strands simultaneously in parallel unlike the sanger sequencing is rapidly spreading. MethodsOne gastric MALT lymphoma and four small intestine MLAT lymphomas were selected and studied using tissue samples embedded in their paraffin. DNA was extracted from tissue samples and quality control was performed. NGS was performed using HemaSCANTM, a custom panel for 426 genes including essential genes for blood cancer. ResultsThe results of NGS revealed the following genomic variants; single nucleotide variations (SNVs), insertions and deletions (InDels) and copy number variations (CNVs). And these genomic variants are reported as annotated, known, and novel variants. Of the annotated variant, ERBB2 gene amplification was confirmed in one patient. Of the known and novel variants, SNV of SETBP6, RUNX1 and KEAP1 gene, InDel of MKI67 gene, CNV of ZNF703 and NOTCH1 gene were confirmed in two or more patients. And InDel with frameshift in BCL10, DDX3X, FOXO3 and MUC2 genes was identified in one patient. ConclusionsSince there are few NGS studies on MALT lymphoma, the various mutations identified in this study cannot be said to be “inactionable”. More studies are needed to determine the association of various genetic mutations with the development of MALT lymphoma. Editorial acknowledgementSeok Jae Huh1, Sung Yong Oh1, Suee Lee1, Ji Hyun Lee1, Sung Hyun Kim1, Min Kyung Park2, and Hyo-Jin Kim1 1Department of Internal Medicine, Dong-A University Hospital, Busan, Republic of Korea, 2Department of Pathology, Dong-A University College of Medicine, Busan, Republic of Korea. Legal entity responsible for the studyThe author. FundingHas not received any funding. DisclosureThe author has declared no conflicts of interest.

1215 Helicobacter pylori Infection in Cancer Patients: MD Anderson Cancer Center Experience

INTRODUCTION: Helicobacter Pylori infection is prevalent worldwide. Up to 50% of the world population is affected, with or without symptoms. H. pylori infection can lead to gastritis, gastric or duodenal ulcers, gastric cancer, and rarely gastric mucosa-associated lymphoid-tissue lymphoma. Patients with cancer are exposed to several factors that can affect H. pylori behavior, such as chemotherapy, radiotherapy, and other treatment modalities. Also, the diminished immunity of cancer patients might be a risk factor for H. pylori or play a role in the responsiveness of H. pylori disease to treatment. Nonetheless, clinical features and outcomes of H. pylori in cancer patients are not well studied. We aimed to describe clinical symptoms, treatments, and outcomes of H. pylori in cancer patients. METHODS: We retrospectively collected information from adult cancer patients who had a diagnosis of H. Pylori after cancer diagnosis between January 2010 and November 2018. Descriptive statistics were used to summarize the data. T-tests and Pearson's Chi-Square were used to compare variables by cancer type. RESULTS: A total of 101 cancer patients diagnosed with H. Pylori by gastric biopsies were included, 61 males and 40 females with a mean age of 58.82 years. Asian was the most common race (n = 28), followed by Hispanic (n = 20) and White (n = 20). Reflux disease was present in 52 patients, hiatal hernia in 19, and Barrett's esophagus in 13. The most common cancer type was those of the gastrointestinal tract (n = 45), followed by lymphoma (n = 16) and breast (n = 14). Regarding cancer treatment, 15 patients had surgery, 51 had chemotherapy, and 35 had chemoradiation. The most common presenting symptom was abdominal pain (n = 45) then bloating (n = 30). Complications of H. pylori infection were manifested as gastric ulcer in 7 patients, duodenal ulcer in 3 and Gastrointestinal bleeding in 4. H. Pylori was treated with Prevpac in 45 patients and Pylera in 36. A 72 patients had response to treatment with the infection recurred in 14 patients. CONCLUSION: In cancer patients with H. Pylori infection, Asian was the most common race, abdominal pain was the most common presenting symptom, GI cancer was the most common malignancy followed by lymphoma and breast cancer. 71% had responded to the treatment.

OP-29 - Synchronous gastric malt lymphoma and adenocarcinoma with concurrent pulmonary malt lymphoma

Deletion of the long arm of chromosome 20 (del(20q)) is observed in 5–10% of patients with myelodysplastic syndromes (MDS). We examined the expression of 28 genes within the common deleted region (CDR) of del(20q), which we previously determined by a CGH array using clinical samples, in 48 MDS patients with (n = 28) or without (n = 20) chromosome 20 abnormalities and control subjects (n = 10). The expression level of 8 of 28 genes was significantly reduced in MDS patients with chromosome 20 abnormalities compared to that of control subjects. In addition, the expression of BCAS4, ADA, and YWHAB genes was significantly reduced in MDS patients without chromosome 20 abnormalities, which suggests that these three genes were commonly involved in the molecular pathogenesis of MDS. To evaluate the clinical significance, we analyzed the impact of the expression level of each gene on overall survival (OS). According to the Cox proportional hazard model, multivariate analysis indicated that reduced BCAS4 expression was associated with inferior OS, but the difference was not significant (HR, 3.77; 95% CI, 0.995-17.17; P = 0.0509). Functional analyses are needed to understand the biological significance of reduced expression of these genes in the pathogenesis of MDS.

Gastric MALT Lymphoma: Outcome with Irradiation after Failure of Primary Antibiotic Therapy

Gastric MALT Lymphoma: Outcome with Irradiation after Failure of Primary Antibiotic Therapy