Gastric Mucosa-associated Lymphoid Tissue Lymphoma Research Articles

Endoscopic morphology of gastric MALT lymphoma correlate with API2/MALT1 fusion and predict treatment response after helicobacter pylori eradication

BackgroundThe presence of API2/MALT1 fusion in gastric mucosa-associated lymphoid tissue (MALT) lymphoma predicts poor response to Helicobacter pylori (Hp) eradication therapy. This study aimed to assess the correlation between endoscopic morphology of MALT lymphoma and API2/MALT1 fusion and evaluate treatment response to Hp eradication based on morphological subtypes.MethodsA retrospective review was conducted on patients diagnosed with gastric MALT lymphoma between January 2011 and December 2022. Endoscopic morphology was categorized as superficial, non-superficial, or mixed type. The superficial type was further classified into gastritis superficial lesion and localized superficial lesion based on border clarity. Logistic regression models evaluated the impact of clinical and endoscopic characteristics on anti-Hp therapy effectiveness.ResultsAmong the 114 patients included, 93 (81.6%) were Hp-positive, and API2/MALT1 fusion was detected in 58 (50.9%) cases, The superficial type was the predominate morphology (73/114, 64%). The regular arrangement of collecting venules (RAC) sign was noted in 21 (18.4%) cases. In superficial subtypes, the RAC signs were more frequently observed in localized lesion than gastritis lesion (35.6% vs. 7.1%, p = 0.01). and the superficial localized lesion was more common in individuals with positive API/MALT1 fusion than negative ones (76.9% vs. 44.1%, p = 0.01). Following Hp eradication, the remission rate for localized lesion was 34.3%, significantly lower than for gastritis lesion (66.7%, p = 0.01). Both endoscopic morphology (OR = 0.26, 95% CI 0.09–0.75) and API2-MALT1 fusion (OR = 14.29, 95% CI 4.19–48.67) impacted the efficacy of anti-Hp therapy. However, multivariate analysis identified API2-MALT1 fusion as the only independent predictor of treatment outcome (OR = 12.18, 95% CI 3.49–42.55, p < 0.001).ConclusionGastric MALT lymphomas with superficial-type morphology, particularly those with defined borders resembling early gastric cancer, were associated with API2/MALT1 fusion and a lower remission rate after Hp eradication therapy. This suggests that endoscopic morphology, along with API2/MALT1 fusion status, could help predict the therapeutic response, with API2/MALT1 fusion serving as a critical indicator of treatment resistance.

Proportion and characteristics of Helicobacter pylori-negative gastric mucosa-associated lymphoid tissue lymphoma: A systematic review and meta-analysis.

While Helicobacter pylori (H. pylori) infection is common in patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, there are still individuals who test negative for it. The proportion and characteristics of these patients remain unclear. We conducted a systematic search of the PubMed, Embase, and Cochrane Library databases for relevant articles. Using a random effects model, we performed a meta-analysis to assess the pooled proportion of gastric MALT lymphoma patients with negative H. pylori tests. Additionally, we compared characteristics between gastric MALT lymphoma patients with and without H. pylori infection to examine clinical features in H. pylori-negative cases. A total of 50 studies involving 6033 patients were included. The overall proportion of gastric MALT lymphoma patients with negative H. pylori tests was 20.5% (95% confidence interval: 17.0%-24.6%). This rate exhibited an increasing trend over the years, particularly in non-Asian countries and in studies published after 2013, as well as in cases with sample sizes exceeding 100 participants, in male individuals, and among those with proximal or multiple lesions, non-superficial type morphology, submucosal invasion, and advanced clinical staging. Compared to H. pylori-positive patients, those who tested negative were more likely to be male, have proximal lesions, exhibit submucosal invasion, and present with an advanced clinical stage. This study provides comprehensive information on the proportion and characteristics of H. pylori-negative gastric MALT lymphoma cases, highlighting the need for future clinical attention to treatment and surveillance in this patient population.

Long-Term Clinical Efficacy of Radiotherapy for Patients with Stage I-II Gastric Extranodal Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue: A Retrospective Multi-Institutional Study.

To evaluate long-term treatment outcomes in patients with localized gastric mucosa-associated lymphoid tissue (MALT) lymphoma treated with radiation therapy (RT). A total of 229 patients who received RT in ten tertiary hospitals between 2010 and 2019 were included in this multi-center analysis. Response after RT was based on esophagogastroduodenoscopy after RT. Locoregional relapse-free survival (LRFS) and disease-free survival (DFS) were evaluated. After a median follow-up time of 93.2 months, 5-year LRFS, DFS, and OS rates were 92.8%, 90.4%, and 96.1%, respectively. LRFS, DFS, and OS rates at 10 years were 90.3%, 87.7%, and 92.8%, respectively. Of 229 patients, 228 (99.6%) patients achieved complete remission after RT. Five-year LRFS was significantly lower in patients with stage IIE than in those with stage IE (77.4% vs. 94.2%, p=0.047). Patients with age ≥ 60 had significantly lower LRFS than patients with age < 60 (89.3% vs. 95.1%, p=0.003). In the multivariate analysis, old age (≥ 60 years) was a prognostic factor for LRFS [hazard ratio (HR) of 3.72 and confidence interval (CI), 1.38-10.03; p=0.009). Grade 2 or higher gastritis was reported in 69 (30.1%) patients. Secondary malignancies including gastric adenocarcinoma, malignant lymphoma, lung cancer, breast cancer, and prostate cancer were observed in 11 (4.8%) patients after RT. Patients treated with RT for localized gastric MALT lymphoma showed favorable 10-year outcomes. Radiation therapy is an effective treatment without an increased risk of secondary cancer. The toxicity for radiotherapy to the stomach is not high.

Correction: From modern pathogenetic insights and molecular understanding to new deescalating therapeutic strategies in gastric MALT-lymphoma.

Correction: From modern pathogenetic insights and molecular understanding to new deescalating therapeutic strategies in gastric MALT-lymphoma.

Reduced-dose radiotherapy for stage IE gastric mucosa-associated lymphoid tissue lymphoma: a multi-institutional prospective study (KROG 16–18)

PurposeDefinitive radiotherapy (RT) of 30 Gy or higher is commonly recommended to treat Helicobacter pylori-independent gastric mucosa-associated lymphoid tissue (MALT) lymphoma with an excellent disease control rate. However, the efficacy of reduced-dose RT has not yet been evaluated in a prospective cohort study. This multi-institutional study aimed to determine the role of reduced-dose RT in the treatment of stage IE gastric MALT lymphoma. MethodsBetween March 2017 and June 2022, 62 patients with histologically confirmed stage IE gastric MALT lymphoma without evidence of H. pylori infection were enrolled. The patients were treated with reduced-dose RT at a total dose of 24–25.5 Gy to the entire stomach. The response to therapy was evaluated by endoscopy with a biopsy of suspicious lesions if necessary. The primary endpoints were 6-month complete remission (CR) and local failure-free survival (LFFS). ResultsAmong 62 patients, 32 (51.6%) were previously treated for H. pylori eradication. Radiotherapy was delivered using 3D-conformal (n=20, 32.3%) or intensity-modulated radiotherapy (n=42, 67.7%). The median follow-up duration was 34.5 months (range, 9.6–68.8 months). The 6-month CR rate was 96.7%. The 5-year LFFS and progression-free survival rates were 92.0% and 90.4%, respectively. None of the patients experienced grade 3 or worse acute toxicities, and grade 2 acute toxicities were reported in 17 patients (27.4%). ConclusionReduced-dose RT exhibited excellent response rates in stage IE gastric MALT lymphoma, comparable to historical controls of standard dose (≥ 30 Gy) radiotherapy, with a minimal toxicity profile. Current prospective evidence strongly supports the use of definitive radiotherapy (24–25.5 Gy) for the treatment of H. pylori-independent stage IE gastric MALT lymphoma.

Long-term Outcomes and Prognostic Factors of Gastric MALT Lymphoma.

This study aimed to evaluate the long-term prognosis of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, including overall survival (OS), remission, and factors associated with an aggressive disease course. Medical records of 153 patients diagnosed with gastric MALT lymphoma between 2013 and 2020 were retrospectively reviewed. Patients experiencing relapse, progression, high-grade transformation, or residual diseasewere included in the aggressive group and were compared with those in the indolent group. Additionally, the endoscopic findings of Helicobacter pylori-negative patients were reviewed. Patient characteristics were as follows: mean age (56.9±11.2 years), sex (male, 51.0%), H. pylori infection (positive, 79.7%), endoscopic location (distal, 89.5%), endoscopic feature (superficial, 89.5%), clinical stage (stage I, 92.8%), invasion depth by endoscopic ultrasound (mucosa, n=115, 75.7%), and bone marrow result (no involvement, n=77, 100.0%). The median follow-up period was 59 months (mean, 61; range, 36-124) and the continuous remission period (n=149) was 51 months (mean, 50; range, 3-112). The 5-year survival rate was 97.7% while the 5-year continuous remission was 88.3%. Factors associated with the patients in the aggressive group were old age, sex(male), and clinical stage II or higher. H. pylori-negative patients' endoscopy revealed a high incidence of atrophic gastritis in the antrum. The long-term prognosis of gastric MALT lymphoma appears indolent and is indicated by the 5-year OS and continuous remission rates. Aggressive disease courses are associated with old age, sex (male), and clinical stage II or higher, but are not related to OS.

Detection, isolation and virulence characterization of Helicobacter suis from pork products aimed to human consumption

Helicobacter suis is the most common non-H. pylori gastric Helicobacter species found in humans. Infection is associated with gastritis, peptic ulcer, gastric MALT lymphoma and neurodegenerative disorders, particularly Parkinson's disease. However, the pathogenicity of this species is still a matter of research, and results of virulence studies and antibiotic susceptibility tests tend to vary between strains. Cholesterol α-glucosyltransferase (αCgT), a known H. pylori virulence factor, appears to be present in most clinical H. suis isolates. The ability to form biofilms also plays a crucial role in the pathogenesis of H. pylori. However, no reports have been published on this ability in H. suis.H. suis is considered an emerging zoonotic pathogen, with pigs being the main source of human infection. However, there is very little information on its presence in pork, mainly due to the difficulties of its culture. Therefore, our aim was to determine the prevalence of H. suis in pork products from our geographical area by PCR and fluorescence in situ hybridisation (FISH), as well as to isolate the bacteria and determine the antibiotic susceptibility patterns, the presence of the αCGT gene and the ability of the isolates to form biofilms.Overall, H. suis was detected in 20 of the 70 (28.6 %) samples analyzed. In 3 of them, H. suis was isolated. The αCGT gene was detected in all isolates and two of them showed a multiresistance pattern. The H. suis reference strain and two of the isolates showed “strong” to “moderate” in vitro biofilm formation ability under optimal growth conditions.Our results seem to indicate that H. suis is significantly prevalent in pork products. The combination of culture with FISH and/or mPCR proved to be a rapid and specific method for the detection, identification and direct visualization of cultivable H. suis cells from pork food products.

S2818 Synchronous Gastric and Colonic MALT Lymphoma: A Rare Occurrence

S2818 Synchronous Gastric and Colonic MALT Lymphoma: A Rare Occurrence

Higher Microbial Abundance and Diversity in Bronchus-Associated Lymphoid Tissue (BALT) Lymphomas than in Non-Cancerous Lung Tissues.

It is well known that the majority of the extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) are associated with microbiota, e.g., gastric MALT lymphoma with Helicobacter pylori. In general, they are very sensitive to low-dose radiotherapy and chemotherapeutic agents. The microbiota profile is not clearly elucidated in bronchus-associated lymphoid tissue (BALT) lymphoma, a rare type of MALT lymphoma in the lung. Thus, this study aimed to clarify the intratumor microbiome in BALT lymphoma using the third-generation NGS method. DNAs were extracted from 12 formalin-fixed paraffin-embedded (FFPE) tumor tissues obtained from BALT lymphoma patients diagnosed between 1990 and 2016. 16S rRNA gene was amplified by polymerase chain reaction. Amplicons were sequenced using a Nanopore platform. Next-generation sequencing analysis was performed to assess microbial profiles. For comparison, FFPE specimens from nine non-cancerous lung tissues were also analyzed. Specific bacterial families including Burkholderiaceae, Bacillaceae, and Microbacteriaceae were associated with BALT lymphoma by a linear discriminant analysis effect size approach. Although the number of specimens was limited, BALT lymphomas exhibited significantly higher microbial abundance and diversity with distinct microbial composition patterns and correlation networks than non-cancerous lung tissues. This study provides the first insight into intratumor microbiome in BALT lymphoma using the third-generation NGS method. A distinct microbial composition suggests the presence of a unique tumor microenvironment of BALT lymphoma.

Treatment Time and Dosimetric Advantage in Cone Beam Computed Tomography-Guided Online Adaptive Radiation Therapy Considering Interfractional and Intrafractional Changes in Patients With Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Radiation therapy is the standard treatment for localized gastric mucosa-associated lymphoid tissue (MALT) lymphoma. The ETHOS system (Varian Medical System) has enabled us to perform cone beam computed tomography (CBCT)-guided online adaptive radiation therapy (oART). This study presents a retrospective dosimetric analysis for interfractional and intrafractional change and treatment time in oART for gastric MALT lymphoma. We included 3 male patients with gastric MALT lymphoma who underwent exhalation breath-hold fasting oART using the SpiroDynr'X system. Treatment details and plans (3 reference [REF] plans, 51 scheduled [SCH] plans, and adapted [ADP] plans) were retrospectively analyzed. Doses to the clinical target volume in planning CT (CTV_REF), CTV1, and CTV2 (representing the stomach in planning and preirradiation CBCT, respectively) and planning target volume (PTV) in the planning CBCT were estimated. D2%, D98%, D50%, and Dmean for these volumes, along with organ-at-risk doses, were examined across the 3 plans. The PTV dose coverage of CTV2 on preirradiation CBCT was calculated. CBCT-guided oART was completed within the scheduled period, using the ADP plans instead of the SCH plans on each treatment day in all cases. The average treatment time was approximately 45 minutes. CTV1 and CTV2 exhibited intrafractional and interfractional variations, fluctuating above and below CTV_REF. Some ADP plans resulted in incomplete PTV coverage of CTV2, but the unincluded volume was <1% of CTV2. D50%, D98%, and Dmean of CTV1, CTV2, and PTV were significantly improved in the ADP plans than in the SCH plans. Moreover, the Dmean to the liver and kidneys was reduced in the ADP plans. CBCT-guided oART in patients with gastric MALT lymphoma demonstrated that ADP plans improved CTV1, CTV2, and PTV doses and reduced the mean bilateral kidney and liver doses, suggesting that it may offer enhanced treatment precision for gastric MALT lymphoma.

Association between Helicobacter pylori and its eradication and the development of cancer

BackgroundHelicobacter pylori (H. pylori) is a gram-negative gastrointestinal pathogen that colonises the human stomach and is considered a major risk factor for gastric cancer and mucosa-associated lymphoid tissue lymphoma. Furthermore,...

Radiation-induced liver disease mimicking liver metastasis after low-dose hepatic irradiation during radiotherapy for gastric mucosa-assisted lymphoid tissue lymphoma: A case report.

Radiation-induced liver disease (RILD) is an established complication of hepatic irradiation that is typically reported in patients receiving high-dose radiotherapy for hepatocellular carcinoma or liver metastases. However, RILD can also occur after unintentional low-dose liver exposure during radiotherapy for other gastrointestinal malignancies when careful precautions are not taken. We report the case of a 44-year-old woman with gastric mucosa-associated lymphoid tissue lymphoma who underwent salvage radiotherapy administered to the entire stomach. One month after completing this radiotherapy, computed tomography and magnetic resonance imaging of the patient's abdomen revealed a 4 cm lesion in the left lateral liver segment, suggestive of metastasis. An ultrasound-guided biopsy was performed, and the histopathological findings were consistent with those of RILD. Conservative management was pursued with close monitoring of liver function tests. The patient's imaging findings and liver enzyme levels normalized approximately 3 months after the initial diagnosis. This case highlights the importance of considering RILD in the differential diagnosis of new hepatic lesions detected after radiotherapy, even in patients with low-dose liver exposure within generally acceptable limits. Careful correlation with the radiotherapy plan is crucial to avoid misdiagnosing RILD as metastatic disease and to guide appropriate management.

An Update on Eradication of Helicobacter Pylori in Iran: A Review.

Helicobacter pylori, the most prevalent infection in the world, has great importance due to being related to peptic ulcer disease, gastric metaplasia, dysplasia, and even gastric adenocarcinoma or mucosa-associated lymphoid tissue (MALT) lymphoma. The standard H. pylori eradication regimen is based on antibiotic susceptibility testing. If susceptibility testing is not available, a standard treatment regimen will be recommended based on records of H. pylori resistance rates to antibiotics in a region or locally proven highly effective regimens (equal to or higher than 90% eradication rate). The aim of this review was to define suitable recommendations for local treatment in different cities of Iran. This review article consists of randomized controlled trials related to H. pylori eradication in Iran. Data including the kind of therapy, number of patients and per-protocol H. pylori eradication rates were recorded in data gathering forms. Data search was conducted in PubMed and Google Scholar databases from 2018 to December 2023. According to our review of Iranian articles regarding first-line H. pylori eradication regimens, these treatment protocols could be recommended: Bismuth-clarithromycin quadruple therapy in Ardabil, bismuth-clarithromycin quadruple therapy with probiotics in Birjand, standard triple therapy in Ilam, bismuth quadruple therapy or bismuth triple therapy or concomitant regimen in Sari, sequential therapy in Tehran and bismuth quadruple therapy in Yazd. These regimes can be extended to other regions that have a similar situation. According to the reports of Iranian researchers, a quinolone-containing regimen (levofloxacin preferred) is recommended for second-line eradication therapy. Various H. pylori eradication regimens can be used as first-line therapy; however, choices for second-line therapy are limited. We recommend the quinolone-containing regimens as the preferred second-line therapy.

Next-Generation-Sequencing of the Human B-Cell Receptor Improves Detection and Diagnosis and Enhances Disease Monitoring in Patients with Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Next-Generation-Sequencing of the Human B-Cell Receptor Improves Detection and Diagnosis and Enhances Disease Monitoring in Patients with Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Prevalence of Helicobacter pylori infection among Patients with Acne Vulgaris

Abstract Background Acne vulgaris is one of the most common dermatologic complaints. About 85% of adolescent population and 3% of the adults between the age of 35-44 years have this disease worldwide. It is a chronic inflammatory disorder of the pilosebaceous unit. Helicobacter pylori is a gastric Gram-negative, spiral-shaped microaerophilic pathogen closely associated with gastric and extra-gastric diseases (chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, gastric cancer, iron deficiency anemia, etc). It has been shown that H. pylori may play a potential pathogenic role in extra-intestinal diseases such as hepatobiliary, respiratory, cardiovascular, and dermatological disorders. The latter included chronic urticaria, psoriasis, henoch-schonlein purpura, and rosacea. Objective To determine the prevalence of H. Pylori infection among AV patients and correlate it with the disease severity. We included 45 patients with AV and 45 matched age and sex apparent healthy controls. Methods This case control study included 45 Patients with AV. They were recruited from the Dermatology outpatient clinic, Ain Shams University Hospitals and Teba specialized hospital in Luxur government. The study also included 45 age and sex matched healthy volunteers as a control group. They were recruited from people who don't have AV attending Al Demerdash Hospital Ain Shams University and Tepa Specialized Hospital. The study was done in the period from November 2021 to October 2022. Results Detection of H. pylori antigen in stool and H. pylori antibody IgG in serum in both groups revealed that the rates of H. pylori antigen in stool and H. pylori antibody IgG in serum were significantly higher in AV patients compared to control subjects. Also the patients with severe AV had statistically significant higher rates of H. pylori antigen in stool and H. pylori antibody in serum as compared to the patients with mild Acne and healthy controls. Also the number of AV involved sites and severity of AV were significantly correlated with H. pylori Ag in stool and H pylori Ab in serum. While there was no statistical significant correlation between (the type of AV, onset of AV and duration of AV) and H. pylori Ag in stool and H. pylori Ab in serum. Conclusion The prevalence of H. pylori infection in patients with acne vulgaris is high so it may represent a risk factor for this skin disease. Also the indicators of H. pylori infection were positively correlated with the severity of AV.

Evaluation of PTV margin in CBCT-based online adaptive radiation therapy for gastric mucosa-associated lymphoid tissue lymphoma.

The aim of this study was to investigate planning target volume (PTV) margin in online adaptive radiation therapy (oART) for gastric mucosa-associated lymphoid tissue (MALT) lymphomas. Four consecutive patients with gastric MALT lymphoma who received oART (30Gy in 15 fractions) on the oART system were included in this study. One hundred and twenty cone-beam computed tomography (CBCT) scans acquired pre- and post-treatment of 60 fractions for all patients were used to evaluate intra- and interfractional motions. Patients were instructed on breath-holding at exhalation during image acquisition. To assess the intrafraction gastric motion, different PTVs were created by isotropically extending the CTV contoured on a pre-CBCT image (CTVpre) at1 mm intervals. Intrafraction motion was defined as the amount of expansion covering the contoured CTV on post-CBCT images (CTVpost). Interfractional motion was defined as the amount of reference CTV expansion that could cover each CTVpre, as well as the evaluation of the intrafractional motion. PTV margins were estimated from the cumulative proportion of fraction covering the intra- and interfractional motions. The extent of expansion covering the CTVs in 90% of fractions was adopted as the PTV margin. The PTV margin for intrafractional gastric motion using the oART system with breath-holding was 14mm. In contrast, the PTV margin for interfractional gastric organ motion without the oART system was 25mm. These results indicated that the oART system can reduce the PTV margin by >10mm. Our results could be valuable data for oART cases.

Unique EPIYT motif CagA gene Helicobacter pylori Bali 01 isolate as the cause of hematemesis in a male gastric ulcer patient in Wangaya General Teaching Hospital Denpasar Bali: a case report

Background: Helicobacter pylori (H. pylori) infection is related with a number of gastrointestinal disorders, including gastritis, peptic ulcer disease, gastric cancer, and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. This case report aims to present an unique EPIYT motif CagA gene H. pylori Bali 01 isolate as the cause of hematemesis in a male gastric ulcer patient Case Presentation: A 70-year-old male Balinese patient came to the hospital due to hematemesis. Esophagogastroduodenoscopy was performed after stabilizing patient condition with prompt treatment and intravenous proton pump inhibitor. Esophagogastroduodenoscopy revealed a solitary giant ulcer in the gastric antrum. Gastric biopsy was performed and histopathology examination revealed a spherical-like organism, confirmed as H. pylori. Biopsy was sent to the Biomedical Laboratory at West Nusa Tenggara, Mataram, Lombok Island. Culture of biopsy and polymerase chain reaction revealed H. pylori, then named H. pylori Bali 01 isolate. Standard protocol of H. pylori eradication is conducted by administration of triple drug therapy consisting of omeprazole, amoxicillin, and clarithromycin for 14 days. Patient was discharged from hospital in stable condition. Helicobacter pylori was successfully eradicated and revealed completely normal gastric antrum in reperformance of esophagogastroduodenoscopy 3 months later. Conclusion: The EPIYA-ABD motif on this H. pylori Bali 01 isolate is distinctively unique from the EPIYT motif on the second EPIYA sequence.

Novel therapeutic regimens against Helicobacter pylori: an updated systematic review.

Helicobacter pylori (H. pylori) is a strict microaerophilic bacterial species that exists in the stomach, and H. pylori infection is one of the most common chronic bacterial infections affecting humans. Eradicating H. pylori is the preferred method for the long-term prevention of complications such as chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. However, first-line treatment with triple therapy and quadruple therapy has been unable to cope with increasing antibacterial resistance. To provide an updated review of H. pylori infections and antibacterial resistance, as well as related treatment options, we searched PubMed for articles published until March 2024. The key search terms were "H. pylori", "H. pylori infection", "H. pylori diseases", "H. pylori eradication", and "H. pylori antibacterial resistance." Despite the use of antimicrobial agents, the annual decline in the eradication rate of H. pylori continues. Emerging eradication therapies, such as the development of the new strong acid blocker vonoprazan, probiotic adjuvant therapy, and H. pylori vaccine therapy, are exciting. However, the effectiveness of these treatments needs to be further evaluated. It is worth mentioning that the idea of altering the oxygen environment in gastric juice for H. pylori to not be able to survive is a hot topic that should be considered in new eradication plans. Various strategies for eradicating H. pylori, including antibacterials, vaccines, probiotics, and biomaterials, are continuously evolving. A novel approach involving the alteration of the oxygen concentration within the growth environment of H. pylori has emerged as a promising eradication strategy.

Gastrointestinal mucosa-associated lymphoma

Mucosa-associated lymphomas of the gastrointestinal tract are aheterogeneous group differing in pathogenesis, localization and therapeutic options. For all of them, differentiated treatment requires an exact determination of lymphoma stage. For gastric MALT lymphoma, the pathogenetic role of Helicobacter pylori infection has become evident in the last 30years. These insights were consequently implemented into clinical practice. Nowadays, Helicobacter pylori eradication is the treatment of choice for gastric MALT lymphoma, leading to complete remission of the lymphoma in the majority of cases. In the absence of success, radiotherapy is available in localized stages I/IIE with excellent results. Immuno-chemotherapy is the domain for advanced stages III/IVE, and surgery plays no role any more. The rare intestinal and colorectal MALT lymphomas require an individualized therapeutic approach.

Response-adapted ultra-low-dose 4 Gy radiation as definitive therapy of gastric MALT lymphoma: a single-centre, pilot trial

Given the favourable prognosis of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, treatment-related toxicity should be minimised. We aimed to evaluate the efficacy of 4 Gy radiotherapy given in a response-adapted approach. We conducted a single-centre, single-arm, prospective trial at MD Anderson Cancer Center (Houston, TX, USA) of response-adapted ultra-low-dose radiotherapy. Eligible patients were 18 years or older and had newly diagnosed or relapsed Helicobacter pylori-negative gastric MALT lymphoma, with stage I-IV disease. Given the expected low toxicity profile of treatment, performance status was not an exclusion criterion. Patients received external beam photon-based radiotherapy for a total dose of 4 Gy in two fractions. Patients with a complete response to 4 Gy via endoscopy and imaging at 3-4 months were observed; patients with a partial response were re-evaluated in 6-9 months. Residual disease at 9-13 months or stable or progressive disease at any time required additional treatment with 20 Gy. The primary endpoint was gastric complete response at 1 year (second evaluation timepoint) after 4 Gy treatment. All analyses were performed as intention to treat. This trial is registered at ClinicalTrials.gov (NCT03680586) and is complete and closed to enrolment. Between March 27, 2019, and Oct 12, 2021, we enrolled 24 eligible patients. The median age of participants was 67 years (IQR 58-74; range 40-85); 15 (63%) were female and nine (37%) male; 18 (75%) were White, four (17%) Asian, and two (8%) Hispanic; 20 (83%) had stage I disease, one (4%) stage II, and three (13%) stage IV. Median follow-up time was 36 months (IQR 26-42). 20 patients (83%) had a complete response to 4 Gy (16 at 3-4 months, four at 9-13 months); two patients received 20 Gy for symptomatic stable disease at 3-4 months and two for residual disease at 9-13 months; all had a complete response. The 3-year local control rate was 96% (95% CI 88-100), with one local relapse at 14 months after 4 Gy radiotherapy salvaged successfully with 20 Gy. One patient with stage IV disease had a distant relapse. The most common adverse events were grade 1 nausea (nine [38%] of 24 patients who received 4 Gy and two [50%] of four patients who received 20 Gy) and grade 1 abdominal pain (five [21%] of 24 and zero of four, respectively). No grade 3 or worse adverse events were noted, including no treatment-related deaths. Most patients had a complete response after 4 Gy radiotherapy; all who required an additional 20 Gy had a complete response within 12 months. This response-adapted strategy could be used to select patients who would benefit from additional radiotherapy and spare others potential associated toxicity. National Cancer Institute.