Definitive Radiotherapy for Stage I Gastric Mucosa-Associated Lymphoid Tissue Lymphoma: A Retrospective Cohort of Unique-Dose Administration of 30 Gy in 15 Fractions and Analysis of Remission Duration.

Background: Gastric mucosa-associated lymphoid tissue (MALT) lymphoma constitutes a significant proportion of primary stomach lymphomas. The optimal dosage for radiotherapy and standardized follow-up protocols are yet to be universally established. This study focuses on stage I gastric MALT lymphoma patients, presenting clinical outcomes of radiotherapy with a unique dose of 30 Gy in 15 fractions and analyzing remission time. Methods: A retrospective cohort study, approved by the institutional review board, included consecutive stage I gastric MALT lymphoma patients undergoing curative radiotherapy between 2008 and 2022. Staging followed the Lugano Modification of the Ann Arbor Staging System. The prescribed dose was uniform dose of 30 Gy in 15 fractions. Results: Fifty-three patients were eligible, with a median age of 63 years. All achieved complete remission (CR), with a median CR time of 3.9 months. At a median follow-up of 56.8 months, no deaths occurred, and three recurrences were noted. The 5-year overall survival, local control survival, and disease-free survival rates were 100%, 100%, and 97.7%, respectively. No severe acute adverse events were observed. Conclusion: The study demonstrates sustained and favorable long-term disease control with a 30 Gy dose in 15 fractions for stage I gastric MALT lymphoma. Comparisons with existing literature highlight the efficacy and safety of radiotherapy in achieving durable remission. Ongoing efforts explore dose reduction and technological advancements to minimize toxicity. This study emphasizes the importance of awaiting clinical response confirmation to validate these outcomes in patients with gastric MALT lymphoma.

Primary gastric diffuse large B-cell lymphoma: A multicentre retrospective study.

Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) accounts for the majority of extra-nodal DLBCL. Even so, literature is lacking on early, localised presentations. We studied a cohort of patients with stage I disease, diagnosed between 2006 and 2018, from six centres between Australia, Canada and Denmark. Our goal was to characterise outcomes, review treatment and investigate the role of interim positron emission tomography (iPET). Thirty-seven eligible patients were identified. The median duration of follow-up was 42.2 months. All received chemoimmunotherapy with 91.9% (n = 34) given rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP). 35.1% (n = 13) underwent consolidative radiotherapy. Eighteen patients were H. pylori positive and 11 had the documentation of H. pylori eradication therapy. The 4-year progression-free survival and overall survival of R-CHOP was 88% (95% CI: 71-95) and 91% (95% CI: 75-97) respectively. All patients who achieved a partial metabolic response or complete metabolic response on iPET went on to achieve complete response at the end of treatment. R-CHOP-based therapy with iPET assessment appears to offer favourable outcomes, with radiotherapy and H. pylori eradication therapy implemented on a case-by-case basis.

Case report: Ultrasound diagnosis of a complicated case of gastric lymphoma misdiagnosed as cirrhosis.

The gastrointestinal (GI) tract is the most common primary site for extranodal lymphomas. The use of ultrasonography for diagnosing gastric lymphomas can be challenging, but ultrasonography still offers some unique advantages in the diagnosis of GI lymphomas. Here, we report a case of gastric lymphoma in a patient with an extensive lesion in which the tumor was complexed with the abdominal organs. CT and endoscopy failed to definitively diagnose the condition in a timely manner. The gastric lymphoma was finally diagnosed with ultrasonography and a treatment plan was implemented.

The role of baseline 2-[18 F]-FDG-PET/CT metrics and radiomics features in predicting primary gastric lymphoma diagnosis.

Diffuse Large B-Cell Lymphomas (DLCBL) and mucosa-associated lymphoid tissue (MALT) are the two most common primary gastric lymphomas (PGLs), but have strongly different features. DLBCL is more aggressive, is frequently diagnosed at an advanced stage and has a poorer prognosis. The aim of this retrospective study was to explore the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (2-[18 F]-FDG-PET/CT) and radiomics features (RFs) in predicting the final diagnosis of patients with PGLs. Ninety-one patients with newly diagnosed PGLs who underwent pre-treatment 2-[18 F]-FDG-PET/CT were included. PET images were qualitatively and semi-quantitatively analyzed by deriving maximum standardized uptake value body weight (SUVbw), maximum standardized uptake value lean body mass (SUVlbm), maximum standardized uptake value body surface area (SUVbsa), lesion to liver SUVmax ratio (L-L SUV R), lesion to blood-pool SUVmax ratio (L-BP SUV R), metabolic tumor volume (gMTV) and total lesion glycolysis of gastric lesion (gTLG), total MTV (tMTV), TLG, and first-order RFs (histogram-related and shape related). Receiver-operating characteristic (ROC) curve analyses were performed to determine the differential diagnostic values of PET parameters. The final diagnosis was DLBCL in 54 (59%) cases and MALT in 37 cases (41%). PGLs showed FDG avidity in 83 cases (90%), 54/54 of DLBCL and 29/37 of MALT. All PET/CT metabolic features, such as stage of disease and tumor size, were significantly higher in DLBCL than MALT; while the presence of H. Pylori infection was more common in MALT. At univariate analysis, all PET/CT metrics were significantly higher in DLBCL than MALT lymphomas, while among RFs only Shape volume_vx and Shape sphericity showed a significant difference between the two groups. In conclusion we demonstrated that 2-[18 F]-FDG-PET/CT parameters can potentially discriminate between DLBCL and MALT lymphomas with high accuracy. Among first-order RFs, only Shape volume_vx and Shape sphericity helped in the differential diagnosis.

Endoscopic Features of Gastric Mucosa-Associated Lymphoid Tissue Lymphoma without Helicobacter pylori.

Although gastric mucosa-associated lymphoid tissue (MALT) lymphoma without Helicobacter pylori (HP) has increased recently, a specific endoscopic classification has not been established; its endoscopic characteristics have not been investigated. In this study, we retrospectively investigated gastric MALT lymphoma without HP in our hospital and assessed differences in the endoscopic findings according to HP infection status. Fifty-seven patients with gastric MALT lymphoma Lugano stage I, diagnosed between January 2013 and March 2023, were divided into three groups (currently HP infected, previously infected, and uninfected), wherein their endoscopic findings were evaluated. Furthermore, the superficial type, as per the classification of Sano et al., was independently subdivided based on the endoscopic differential diagnoses, as follows: atrophic gastritis-like, angiodysplasia-like, superficial gastritis-like, and undifferentiated carcinoma-like. Compared with the currently infected group, the HP-uninfected group tended to have more small lesions without erosion and more discolored, undifferentiated carcinoma-like depressed lesions. In addition, the positive rate of the tree-like appearance (TLA) and ballooning characteristics of gastric MALT lymphoma in magnified findings was lower in the HP-uninfected group. In patients without HP infection, MALT lymphoma should be excluded, even in the absence of suspicious magnifying findings such as TLA or ballooning.

The Great Mimicker of Gastric Cancer: A Case Report of Ménétrier's Disease.

This is the case of a 52-year-old Indian lady who presented with hematemesis, severe anemia, and an abdominal lump in cardiac failure. On radiographic evaluation, the lesion appeared to be gross circumferential asymmetric proximal gastric wall thickening, with suspicion of gastric lymphoma or tubercular hypertrophic gastritis. After stabilization with multiple transfusions, she underwent proximal D2 gastrectomy with esophago-gastric anastomosis and a total splenectomy. Grossly, the gastric rugae appeared to be hypertrophied and firm. No growth was identified grossly; however, necrotic areas were identified at the distal end. Microscopic examination of multiple sections studied showed significant foveolar hyperplasia, tortuous glands, and a few cystically dilated foveolar glands, which were limited up to the muscle layer. Mild serosal congestion was seen. No atypia or invasion was seen. An impression to consider is the possibility of Ménétrier's disease (MD). MD is an acquired protein-losing enteropathy with giant gastric rugal folds, decreased acid secretion, and increased gastric mucous production. Radiographically, endoscopically, and grossly, the condition can be confused with malignant lymphoma or carcinoma. It is difficult to diagnose, and histopathological confirmation of the resected specimen is needed for a definitive diagnosis. Our intention in presenting this case is to emphasize that MD can present as massive hematemesis and should be considered in a differential diagnosis. Surgical treatment by total or partial gastrectomy is recommended for cases with persistent, debilitating symptoms or a risk of cancer.

A rare case of perforated gastric lymphoma presenting a life-threatening condition: A case report.

INTRODUCTION AND IMPORTANCE: Gastric lymphomas are non-Hodgkin's lymphomas originating from mucosa-associated lymphoid tissue (MALT). Surgical intervention is recommended in cases of complications such as obstruction, bleeding, or perforation, although the choice of treatment can be a subject of debate and may entail life-threatening risks. This case report aims to describe a complex case of gastric MALT lymphoma with perforation requiring surgical intervention. CASE PRESENTATION: A 47-year-old patient with a history of extranodal marginal zone B cell lymphoma presented to the Emergency Department with epigastric pain. Physical examination revealed a patient with hemodynamic instability and generalized abdominal tenderness. An abdominal CT scan revealed intraperitoneal air and effusion, along with a gastric wall defect. An emergent laparotomy was performed, revealing widespread purulent peritonitis resulting from a centimetric perforation in the anterior wall of the stomach near the lesser curvature. Following peritoneal lavage, we repaired the perforation and performed external drainage. The postoperative course was complicated by renal failure, and the patient succumbed to the illness two days after surgery. CASE DISCUSSION: Gastric lymphomas, primarily linked to H. pylori infection. Diagnosis relies on endoscopy and histopathology. Endoscopic manifestations vary, making biopsy crucial. H. pylori eradication is the initial treatment, but resistance may require chemotherapy. Gastric lymphoma complications include perforation, with life-threatening consequences. Perforations can occur due to lymphoma or chemotherapy. Timely intervention with suturing is crucial for patient management. The postoperative course is difficult to manage due to the immune system deficiency. CONCLUSION: Bowel perforation in gastric lymphomas significantly contributes to morbidity and mortality. Early diagnosis and emergent surgery are imperative to mitigate complications and reduce septicemia even in young patients.

Role of endoscopic ultrasound-guided tissue acquisition for the diagnosis of gastric wall thickening: a retrospective study with meta-analysis.

Background: Tissue acquisition from a thickened gastric wall using biopsy forceps may not always lead to diagnosis, given the submucosal location of the pathology. Endoscopic ultrasound (EUS)-guided tissue acquisition (TA) may serve as a minimally invasive diagnostic tool in such cases. Hence, we aimed to assess the diagnostic outcome and safety of EUS-TA from thickened gastric walls. Methods: Data from patients with gastric wall thickening undergoing EUS-TA at 5 tertiary care centers from August 2020 to August 2022 were retrospectively analyzed. These data were pooled with studies obtained from a comprehensive search of Medline, Embase and Scopus from January 2000 to November 2022 and a meta-analysis was performed. Pooled event rates were calculated using an inverse variance model. Results: The search strategy yielded 13 studies that were combined with data from 30 patients from our centers; a total of 399 patients were included in the analysis. The pooled rate of sample adequacy was 94.1% (95% confidence interval [CI] 90.0-98.2), while the pooled rate of diagnostic accuracy was 91.3% (95%CI 87.0-95.5). The pooled sensitivity and specificity for diagnosing malignant lesions with EUS-TA from gastric wall thickening were 94.8% (95%CI 91.3-97.2) and 100% (95%CI 93.6-100), respectively. There were no reported adverse events in any of the studies. Conclusions: EUS-TA offers a safe and accurate diagnostic modality for the etiological diagnosis of thickened gastric walls. Further research is required to identify the needle type and optimal technique for improving outcomes.

Clinical relevance of molecular aspects in extranodal marginal zone lymphoma: a critical appraisal.

Extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) is among the more common types of lymphoma accounting for up to 8% of newly diagnosed lymphoma cases. As opposed to other B-cell lymphomas, however, no predominant genetic hallmark has been defined in MALT lymphoma, but different localizations appear to be affected by different, sometimes distinct changes. Nonetheless, a high proportion of these genetic changes reported in MALT lymphomas dysregulate the pathways leading to NF-kB activation. t(11;18)(q21;q21)/BIRC3::MALT1 appears to be MALT lymphoma specific and is found in 24% of gastric and 40% of pulmonary MALT lymphomas. The translocation is associated with more disseminated disease in gastric MALT lymphoma and is found in a large percentage of patients whose lymphoma is unresponsive to antibiotic eradication of Helicobacter pylori. In addition to t(11;18)(q21;q21), nuclear expression of BCL10 or NF-kB appears to be highly associated with lymphoma cell survival independence of H. pylori-mediated stimulations. Antibiotic eradication, however, is the recommended therapy of choice irrespective of genetic findings, and molecular analysis is not required before initiation of therapy. The influence of genetic translocations including t(11;18)(q21;q21) on systemic therapies, however, is less clearly defined. While small series have shown no influence on the outcome for treatment with the anti-CD20 antibody rituximab (R) or treatment with cladribine (2-CdA), conflicting data have been reported for alkylating agents, especially chlorambucil and the combination of R + chlorambucil. None of other genetic changes seen in MALT lymphoma to date has discernible value in routine clinical applications, but recent data suggest that changes in TNFAIP3(A20), KMTD2 and CARD11 might be associated with response to Bruton kinase inhibitors.

The Effect of Surgery on the Prognosis of Gastric Lymphoma: A Meta-analysis.

OBJECTIVE: Surgery is an effective clinical approach that has been used for the treatment of gastric lymphoma. However, its specific effect on the prognosis of patients with gastric lymphoma remains largely unknown. The current meta-analysis aimed to identify the effect of surgery on the prognosis of gastric lymphoma. METHODS: We searched the MEDLINE, Embase, and Cochrane Central databases to obtain relevant studies investigating the influence of surgery on overall survival (OS) and relapse-free survival (RFS). We extracted the hazard ratios (HRs) and associated 95% confidence intervals (CIs) of each included report for pooled analysis. We assessed heterogeneity (I2 statistic) and funnel plots to select the data models and evaluate publication bias. RESULTS: Ultimately, we included 12 studies containing 26 comparisons in the current quantitative meta-analysis. The analysis revealed that surgery had no significant effect on OS (HR .83, P = .13) or RFS (HR .78, P = .08). However, subgroup analysis revealed that the effect of surgery on OS differed significantly between the surgery plus conservative therapy subgroup and the conservative therapy alone groups, with HR = .69 (P = .01). No significant publication bias was detected regarding the main outcomes. CONCLUSION: Surgery had a limited effect on the prognosis of patients with gastric lymphoma. However, the use of surgery as an additional therapy may confer potential benefits. This was an interesting research direction, and additional high-quality, large-scale randomized controlled trials should be conducted.

The clinicopathological characteristics of gastric cancer and precancerous conditions in gastric DLBCL and MALT lymphoma patients: a multi-center retrospective study.

OBJECTIVE: The objective of this study is to explore the clinicopathological characteristics of gastric cancer and precancerous conditions in patients with primary gastric lymphoma. METHODS: We analyzed 474 cases of primary gastric lymphoma, mainly DLBCL and MALT, from three clinical centres retrospectively, and compared the clinicopathological parameters of primary gastric lymphoma patients complicated with gastric cancer, precancerous conditions, or with no complications. RESULTS: A total of 5.1% of the patients with primary gastric lymphoma were diagnosed with gastric cancer, including metachronous gastric adenocarcinoma (3.2%) and synchronous gastric adenocarcinoma (1.9%). Of the patients with gastric lymphoma, 14.6% had precancerous conditions including atrophy (14.6%), intestinal metaplasia (8.9%), and low-grade intraepithelial neoplasia (1.9%). Primary gastric lymphoma patients with an ulcerative type (p = 0.009) and Lugano classification stage IIE + IV (p < 0.001) lymphoma had a higher risk of complicating with gastric cancers or precancerous conditions. The rate of infection of Helicobacter pylori (Hp) was 68.4% in patients with primary gastric lymphoma, which was higher in patients with MALT lymphoma (p < 0.001), Lugano classification stage I + II (p < 0.001), and patients complicated with precancerous conditions and gastric cancer (p < 0.001), especially gastric cancer of the intestinal type (p = 0.04). Gastric cancer (95.8%) and precancerous conditions (91.3%) occurred mostly in Hp-infected primary gastric lymphoma patients, with a minor subset of Hp-eradicated patients. Primary gastric lymphoma patients had a higher detection rate of early gastric cancer (25.0%) and a five-year survival rate (40.0%) than the general Chinese population. CONCLUSIONS: Patients with primary gastric lymphoma have a high risk of developing gastric cancer and precancerous conditions, and this risk may be related to Helicobacter pylori infection. Follow-up of primary gastric lymphoma provides an opportunity for the detection of early gastric cancer.Key messages5.1% of the patients with primary gastric lymphoma were diagnosed with gastric cancer.14.6% of the patients with gastric lymphoma had premalignant lesions including atrophy (14.6%), intestinal metaplasia (8.9%), and low-grade intraepithelial neoplasia (1.9%).Primary gastric lymphoma patients complicating with gastric cancer had a higher infection rate of Helicobacter pylori (100.0%), a detection rate of early gastric cancer (25.0%) and a five-year survival rate (40.0%) than the general Chinese population.

A rare case of primary gastric Hodgkin lymphoma in an adolescent with Nijmegen breakage syndrome.

BACKGROUND: Nijmegen Breakage Syndrome (NBS) is a rare autosomal recessive DNA repair disorder that increases risk of hematological malignancy. Primary gastric malignancies are exceedingly rare in pediatric patients and not typically high on the differential of abdominal pain. CASE PRESENTATION: A 14-year-old male with NBS presented with persistent abdominal pain and was diagnosed with primary Hodgkin disease of the stomach. CONCLUSIONS: In pediatric patients with predisposition to malignancies, such as those with underlying chromosome instability disorders, all symptoms must be carefully considered.

Gastric Diffuse Large B-Cell Lymphoma in an Adolescent: A Case Report.

Non-Hodgkin lymphoma (NHL) is the 11th most common cancer worldwide and the 4th most common pediatric cancer. The GI tract is the most common extranodal site of NHL, making up about 30-40% of extranodal cases. The median age at diagnosis for gastrointestinal NHL (gNHL) is around 61. On the other hand, gNHL is very rare in the pediatric population. Herein, we report the case of a 15-year-old girl who complained of abdominal pain and vomiting after meals, with severe B symptoms (fever, night chills, and severe weight loss). Esophagogastroduodenoscopy showed a mass in the lesser curvature of the stomach. Subsequent biopsy and immunostaining of the sample confirmed the diagnosis of diffuse large B-cell lymphoma. CT and PET-CT scans indicated the involvement of mesenteric and lesser omental lymph nodes. Later on, the patient started an R-CHOP chemotherapy regimen. In this report, we aim to shine the light on such a rare disease in this age group.

Estimating the prevalence of Epstein-Barr virus in primary gastric lymphoma: a systematic review and meta-analysis.

The stomach is a common site for extranodal non-Hodgkin's lymphoma. While Helicobacter pylori (H. pylori) is the main established risk factor for primary gastric lymphoma, a fraction could be aetiologically associated with Epstein-Barr virus (EBV), a known haematolymphoid carcinogen. We systematically searched five databases from 1 January 1990 until 31 May 2022 for studies reporting EBV prevalence in gastric lymphoma tumour tissue by in-situ hybridisation (ISH) for EBV-encoded small RNA (PROSPERO CRD42020164473). We included representative series of more than five gastric lymphoma cases. Pooled prevalence and corresponding 95% confidence intervals (CI) of EBV in gastric tumour cells were calculated for two major gastric B-cell lymphoma types, mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B-cell lymphoma (DLBCL). When available, we also extracted data on H. pylori prevalence and survival by EBV status. We found ten studies including 194 cases of gastric MALT lymphoma and 11 studies including 643 cases of gastric DLBCL. EBV prevalence was 2.2% (95% CI: 0.5-13.3) in gastric MALT lymphoma and 11.0% (95% CI: 5.2-20.0) in gastric DLBCL. In a subset of studies, the prevalence of H. pylori was higher in gastric MALT lymphoma (51/69) compared to gastric DLBCL (62/102). Overall, our findings suggest that EBV is rarely seen in MALT lymphoma but is associated with around 10% of gastric DLBCL, similar to the proportion observed at other primary sites. EBV-related lymphoma adds a small number of cases to the burden of cancer that could be prevented by the future development of a vaccine against EBV.

Gastric perforation secondary to T-cell lymphoma.

Introduction: Malignant primary lymphoma represents only 1%-5% of all gastric tumours. Spontaneous gastric perforation in the absence of chemotherapy in these cases is extremely rare. The vast majority of primary gastric lymphomas have a B-cell phenotype that originates from mucosa-associated lymphoid tissue and primary gastric lymphomas with a T-cell phenotype are rarely reported. This report describes a case of a primary gastric T-cell malignant lymphoma associated to spontaneous perforation and peritonitis. Case presentation: An 80-year-old woman referring 24 hours of abdominal pain associated to cognitive impairment consulted to our Emergency Department. Her past medical history revealed smoking, hypothyroidism, dilated cardiomyopathy, hypertension, celiac disease with poor adherence to gluten-free diet and a Non-Hodgkin T cell lymphoma associated to enteropathy in 2010. At physical examination, she presented with tachycardia, hypotension and abdominal tenderness. Lab test revealed low red cell count and an abdomen computed tomography scan showed pneumoperitoneum secondary to a large gastric perforation located in the anterior wall of the antrum. Urgent surgery was performed. At exploratory laparoscopy, a 5 cm perforation of the anterior wall of prepyloric antrum was observed associated to a 4-quadrant peritonitis. Conversion to open surgery was decided to perform an open antrectomy and Billroth II gastro-jejunostomy. The patient was transferred to ICU after surgery under mechanical respiratory assistance for closed monitoring but evolved with a cardiogenic shock and deceased on the first postoperative day. The final histopathological and immunohistochemical analysis reported enteropathy-associated T-cell lymphoma of gastric localisation with concomitant celiac disease. Discussion: We present a rare case of a patient with a history of celiac disease who developed a gastric perforation secondary to an enteropathy-associated T-cell lymphoma of gastric localisation. To the best of authors' knowledge, there have been reported less than 30 cases of spontaneous perforation of gastric lymphoma in the absence of chemotherapy in the last 35 years. Malignant gastric lymphoma, accounting only for 1% of primary gastric malignancies, is usually a diffuse large B-cell lymphoma. Incidence of perforation of gastric lymphomas in patients receiving chemotherapy rounds 0.9%-1.1%. However, it is a rare condition in patients not receiving chemotherapy. Conclusion: This is a rare case of a patient with an enteropathy-associated T-cell lymphoma of gastric localisation, who developed a spontaneous gastric perforation in the absence of chemotherapy. Despite it is a rare condition, it must be suspected in patients with a history of lymphoma in the context of acute abdominal pain.

Helicobacter pylori-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphoma Presenting as Massive Gastrointestinal Bleed.

This case reports a patient that represents the minority of patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma who do not have underlying Helicobacter pylori gastritis. Gastric MALT lymphoma is a type of primary gastric lymphoma (PGL), which are extremely rare gastric malignancies characterized by proliferation of B-cells and infiltration of lymphoid tissue leading to destruction of gastric glands. Development of gastric MALT lymphoma is associated with H. pylori gastritis. Patients typically present with a wide range of symptoms including but not limited to epigastric pain, weight loss, gastrointestinal bleeding and gastric wall perforation. Gastric MALT lymphoma presenting as a massive gastrointestinal bleed is quite rare and only a few cases have been documented. Our case demonstrates that it is important to recognize that acute presentations of this disease may also occur.

A lumpy bumpy stomach: The more the murkier.

This report describes the radiological and endoscopic findings in a 54-year-old male who presented with epigastric pain. The patient underwent an upper gastrointestinal (GI) barium study followed by axial imaging, which demonstrated nodular gastric wall thickening. The classic findings of aggressive primary gastric diffuse large B-Cell lymphoma are presented with a brief review differentiating the pathological subtypes, important for patient prognostication and planning of therapy.

A phase 2 trial of deep-inspiration breath hold in radiotherapy of gastric lymphomas.

Background and purpose: Radiotherapy (RT) is an important part in the treatment of gastric lymphomas and the prognosis after radiotherapy is very good with a good chance of long-term survival, so prevention of long-term adverse effects is important. In patients with gastric lymphomas cardiac late effects are of most concern. The aim of this study was to assess if the dose to the heart could be reduced with deep inspiration breath-hold (DIBH) without compromising the dose to the target or increasing the risk of other late effects. Methods and patients: Fifteen patients with gastric lymphoma were included. RT plans were made using DIBH and Free breathing (FB) scans. Clinical target volume (CTV) was the stomach plus 1 cm margin. The heart and surrounding organs at risk (OAR) were contoured. Two sets of plan comparisons were made, one with 1 cm CTV to planning target volume (PTV) margin in both DIBH and FB and one set with an additional 5 mm CTV to PTV margin in cranio-caudal direction with FB. Datasets were analysed with Wilcoxon signed rank test for non-parametric paired data. Results: All patients tolerated the procedures and were treated with volumetric arc therapy technique in DIBH. Target coverage was kept equal between FB and DIBH, while a statistically significant reduction of the estimated does to the heart was seen with DIBH. Median mean heart dose was reduced from 7.1 Gy (5.7-12) to a median of 3.2 Gy (1.2-7.0) and heart V20 from a median of 54 (17-106) cm3 to 15. (0.0-78) cm3. The estimated mean doses to the liver, duodenum, pancreas and spinal cord were at the same level. Conclusion: This clinical trial of RT with DIBH for gastric lymphomas showed that the heart dose could be reduced without compromising PTV coverage. The doses to abdominal OARs were similar with FB and DIBH.

A dynamic predictive nomogram of long-term survival in primary gastric lymphoma: a retrospective study.

BACKGROUND: Primary gastric lymphoma (PGL) is the most common extranodal non-Hodgkin lymphoma (NHL). Due to the rarity of the disease, it is important to create a predictive model that provides treatment and prognosis for patients with PGL and physicians. METHODS: A total of 8898 and 127 patients diagnosed with PGL were obtained from the SEER database and from our Cancer Center as training and validation cohorts, respectively. Univariate and multivariate Cox proportional hazards models were used to investigate independent risk factors for the construction of predictive survival nomograms, and a web nomogram was developed for the dynamic prediction of survival of patients with PGL. The concordance index (C-index), calibration plot, and receiver operating characteristics (ROC) curve were used to evaluate and validate the nomogram models. RESULTS: There were 8898 PGL patients in the SEER cohort, most of whom were married men over the age of 60, 16.1% of the primary tumors were localized in the antrum and pylori of the stomach, which was similar to the composition of 127 patients in the Chinese cohort, making both groups comparable. The Nomogram of overall survival (OS) was compiled based on eight variables, including age at diagnosis, sex, race, marital status, histology, stage, radiotherapy and chemotherapy. Cancer-specific survival (CSS) nomogram was developed with eight variables, including age at diagnosis, sex, marital status, primary tumor site, histology, stage, radiotherapy and chemotherapy. The C-index of OS prediction nomogram was 0.948 (95% CI: 0.901-0.995) in the validation cohort, the calibration plots showed an optimal match and a high area below the ROC curve (AUC) was observed in both training and validation sets. Also, we established the first web-based PGL survival rate calculator ( https://yangjinru.shinyapps.io/DynNomapp/ ). CONCLUSION: The web dynamic nomogram provided an insightful and applicable tool for evaluating PGL prognosis in OS and CSS, and can effectively guide individual treatment and monitoring.