Primary lymphomas in the gastrointestinal tract

Efficacy and side effects of anti-CD19 CAR T-cell therapy in patients with relapsed/refractory gastrointestinal lymphoma

INTRODUCTION

Although anti-CD19 chimeric antigen receptor (CAR) T cell therapy was approved as a very effective salvage strategy in relapsed/refractory (R/R) B cell lymphoma, the experience in R/R gastrointestinal (GI) lymphoma is still insufficient.

METHODS

We summarized the efficacy and side effects of anti-CD19 CAR T-cell therapy in 12 patients with R/R GI lymphoma. Based on literature, the R/R GI lymphoma patients were divided into subgroups with different characteristics: Bulky/No bulky disease, Gastric/Gastrointestinal involvement, Gastrointestinal/Combined extra-gastrointestinal lesions, Ulcer/Lumps or nodules type, With/without gastrointestinal bleeding.

RESULTS

The objective response rate (ORR) was 66.67% in these 12 patients. The ORR was 83.33% in no bulky disease group, 80.00% in gastric involvement group, 100.00% in ulcer type group, and 80.00% in no gastrointestinal bleeding group. The CR rate was 33.33% in these 12 patients. The CR was 50.0% in no bulky disease group, 60.00% in gastric involvement group, and 80.00% in ulcer type group. The PFS and OS rate of the 12 patients at 6 months after infusion were 54.55% and 58.33%, respectively. The overall survival (OS) at 6 months was higher in no bulky disease group. There was no difference of the OS or the progression free survival (PFS) at 6 months between the other groups. The mean peak of CAR-T cells and Cytokine Release Syndrome (CRS) grade were higher in gastrointestinal lesions group. The mean peak of IFN-γ and CRS grade were higher in gastrointestinal bleeding group. Four out of six patients in group of gastrointestinal lesions group were patient with high tumor burden. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding.

CONCLUSIONS

The ORR and CR of high tumor load, gastrointestinal involvement, lumps or nodules type and gastrointestinal bleeding group were lower. The CRS grade was higher in gastrointestinal lesions group and in gastrointestinal bleeding group. Patients with gastrointestinal involvement only were at higher risk for gastrointestinal bleeding.

Deep learning model for predicting the survival of patients with primary gastrointestinal lymphoma based on the SEER database and a multicentre external validation cohort

PURPOSE

Due to the rarity of primary gastrointestinal lymphoma (PGIL), the prognostic factors and optimal management of PGIL have not been clearly defined. We aimed to establish prognostic models using a deep learning algorithm for survival prediction.

METHODS

We collected 11,168 PGIL patients from the Surveillance, Epidemiology, and End Results (SEER) database to form the training and test cohorts. At the same time, we collected 82 PGIL patients from three medical centres to form the external validation cohort. We constructed a Cox proportional hazards (CoxPH) model, random survival forest (RSF) model, and neural multitask logistic regression (DeepSurv) model to predict PGIL patients' overall survival (OS).

RESULTS

The 1-, 3-, 5-, and 10-year OS rates of PGIL patients in the SEER database were 77.1%, 69.4%, 63.7%, and 50.3%, respectively. The RSF model based on all variables showed that the top three most important variables for predicting OS were age, histological type, and chemotherapy. The independent risk factors for PGIL patient prognosis included sex, age, race, primary site, Ann Arbor stage, histological type, symptom, radiotherapy, and chemotherapy, according to the Lasso regression analysis. Using these factors, we built the CoxPH and DeepSurv models. The DeepSurv model's C-index values were 0.760 in the training cohort, 0.742 in the test cohort, and 0.707 in the external validation cohort, which demonstrated that the DeepSurv model performed better compared to the RSF model (0.728) and the CoxPH model (0.724). The DeepSurv model accurately predicted 1-, 3-, 5- and 10-year OS. Both calibration curves and decision curve analysis curves demonstrated the superior performance of the DeepSurv model. We developed the DeepSurv model as an online web calculator for survival prediction, which can be accessed at http://124.222.228.112:8501/ .

CONCLUSIONS

This DeepSurv model with external validation is superior to previous studies in predicting short-term and long-term survival and can help us make better-individualized decisions for PGIL patients.

Nomogram based on computed tomography images and clinical data for distinguishing between primary intestinal lymphoma and Crohn's disease: a retrospective multicenter study

Background

Differential diagnosis of primary intestinal lymphoma (PIL) and Crohn's disease (CD) is a challenge in clinical diagnosis.

Aims

To investigate the validity of the nomogram based on clinical and computed tomography (CT) features to identify PIL and CD.

Methods

This study retrospectively analyzed laboratory parameters, demographic characteristics, clinical manifestations, and CT imaging features of PIL and CD patients from two centers. Univariate logistic analysis was performed for each variable, and laboratory parameter model, clinical model and imaging features model were developed separately. Finally, a nomogram was established. All models were evaluated using the area under the curve (AUC), accuracy, sensitivity, specificity, and decision curve analysis (DCA).

Results

This study collected data from 121 patients (PIL = 69, CD = 52) from Center 1. Data from 43 patients (PIL = 24, CD = 19) were collected at Center 2 as an external validation cohort to validate the robustness of the model. Three models and a nomogram were developed to distinguish PIL from CD. Most models performed well from the external validation cohort. The nomogram showed the best performance with an AUC of 0.921 (95% CI: 0.838-1.000) and sensitivities, specificities, and accuracies of 0.945, 0.792, and 0.860, respectively.

Conclusion

A nomogram combining clinical data and imaging features was constructed, which can effectively distinguish PIL from CD.

Clinical and endoscopic features of primary small bowel lymphoma: a single-center experience from mainland China

Objective

The worldwide incidence of primary small intestinal lymphoma (PSIL) is increasing. However, little is known about the clinical and endoscopic characteristics of this disease. The aim of this study was to investigate the clinical and endoscopic data of patients with PSIL, with the goal of enhancing our understanding of the disease, improving diagnostic accuracy, and facilitating more accurate prognosis estimation.

Methods

Ninety-four patients diagnosed with PSIL were retrospectively studied at Qilu Hospital of Shandong University between 2012 and 2021. The clinical data, enteroscopy findings, treatment modalities, and survival times were collected and analyzed.

Results

Ninety-four patients (52 males) with PSIL were included in this study. The median age of onset was 58.5 years (range: 19-80 years). Diffuse large B-cell lymphoma (n=37) was the most common pathological type. Abdominal pain (n=59) was the most frequent clinical presentation. The ileocecal region (n=32) was the most commonly affected site, and 11.7% of patients had multiple lesions. At the time of diagnosis, the majority of patients (n=68) were in stages I-II. A new endoscopic classification of PSIL was developed, including hypertrophic type, exophytic type, follicular/polypoid type, ulcerative type, and diffusion type. Surgery did not show a significant increase in overall survival; chemotherapy was the most commonly administered treatment. T-cell lymphoma, stages III-IV, "B" symptoms, and ulcerative type were associated with poor prognosis.

Conclusion

This study provides a comprehensive analysis of the clinical and endoscopic features of PSIL in 94 patients. This highlights the importance of considering clinical and endoscopic characteristics for accurate diagnosis and prognosis estimation during small bowel enteroscopy. Early detection and treatment of PSIL is associated with a favorable prognosis. Our findings also suggest that certain risk factors, such as pathological type, "B" symptoms, and endoscopic type, may affect the survival of PSIL patients. These results underscore the need for careful consideration of these factors in the diagnosis and treatment of PSIL.

A Novel Prognostic Model for Patients with Primary Gastric Diffuse Large B-Cell Lymphoma

Objectives. Primary gastric diffuse large B-cell lymphoma (PG-DLBCL) is a common phenotype of extranodal non-Hodgkin’s lymphoma (NHL). This research aims to identify a model for predicting overall survival (OS) and cancer-specific survival (CSS) in PG-DLBCL. Methods. A total of 1716 patients diagnosed with PG-DLBCL between 1975 and 2017 were obtained from the SEER database and further randomly divided into the training and validating cohorts at a ratio of 7 : 3. Univariate and multivariate cox analyses were conducted to determine significant variables for the construction of nomogram. The performance of the model was then assessed by the concordance index (C-index), the calibration plot, and the area under the receiver operating characteristic (ROC) curve (AUC). Results. Multivariate analysis revealed that age, race, insurance status, Ann Arbor stage, marital status, chemotherapy, and radiation therapy all showed a significant association with OS and CSS. These characteristics were applied to build a nomogram. In the training cohort, the discrimination of nomogram for OS and CSS prediction was excellent (C-index = 0.764, 95% CI, 0.744–0.784 and C-index = 0.756, 95% CI, 0.732–0.780). The AUC of the nomogram for predicting 3- and 5-year OS was 0.779 and 0.784 and CSS was 0.765 and 0.772. Similar results were also observed in the internal validation set. Conclusions. We have successfully established a novel nomogram for predicting OS and CSS in PG-DLBCL patients with good accuracy, which can help physicians to quickly and accurately complete the evaluation of survival probability, risk stratification, and therapeutic strategy at diagnosis.

Primary small intestinal extranodal NK/T cell lymphoma, nasal type with kidney involvement: a rare case report and literature review

Background

Extranodal NK/T cell lymphoma, nasal type (EN-NK/T-NT) is a rare and aggressive type of non-Hodgkin’s lymphoma. EN-NK/T-NT seldom occurs in the gastrointestinal tract, and renal involvement is relatively rare.

Case presentation

Here we report a case of primary small intestinal EN-NK/T-NT with kidney involvement. We present the case of a 71-year-old female who was admitted to our hospital for coronary heart disease with a fever of unknown origin. Laboratory examination showed renal impairment and PET/CT showed a locally thickened wall of the small intestine, abnormally increased FDG metabolism in the right lower abdomen, and multiple slightly high-density masses with abnormal increased FDG metabolism in the right kidney. The gross specimen showed a grayish-white lump located in the ileum approximately 15 cm away from the ileocecum, and two grayish-white lumps located in the upper and lower poles of the right kidney, respectively. The pathological diagnosis was EN-NK/T-NT. The patient died approximately 10 months after the operation.

Conclusion

EN-NK/T-NT is a rare type of non-Hodgkin’s lymphoma and may develop insidiously, with fever as the only clinical manifestation. The disease was found to be difficult to diagnose in the early stage, resulting in a highly aggressive clinical course and short survival time.

Protein Loss Enteropathy as an Initial Presentation of Gastric Epstein–Barr Virus Lymphoma

Protein loss enteropathy (PLE) is a complex disease process that can result in potentially fatal protein losses. Gastrointestinal protein losses usually arise from damage to the gastrointestinal mucosa or from lymphatic obstruction. The goal of management is to identify and treat the underlying causes and maintain normal serum protein levels. Here, we present a patient with diarrhea and generalized edema, with decreased serum albumin and gamma-globulin levels, concerning for protein loss enteropathy. He was ultimately found to be positive for HIV infection, and his stool alpha-1 antitrypsin levels were diagnostic of protein loss enteropathy. His endoscopic and histologic evaluation revealed gastric Epstein–Barr virus-encoded small RNA- (EBER-) positive lymphoma. Though gastrointestinal lymphomas are known to cause PLE, this will be the first documented case of EBER-positive gastric lymphoma presenting with PLE. We hope to bring awareness to this unique presentation to aid in expedient diagnosis and treatment to avoid delays in treatment and potentially fatal outcomes.

A New Staging System Based on the Dynamic Prognostic Nomogram for Elderly Patients With Primary Gastrointestinal Diffuse Large B-Cell Lymphoma

Objective

The purpose of this study is to establish an accurate prognostic model based on important clinical parameters to predict the overall survival (OS) of elderly patients with primary gastrointestinal diffuse large B-cell lymphoma (EGI DLBCL).

Methods

The Cox regression analysis is based on data from the Surveillance, Epidemiology, and End Results (SEER) database.

Results

A total of 1,783 EGI DLBCL cases were eligible for the study [median (interquartile range, IQR) age, 75 (68–82) years; 974 (54.63%) males], of which 1,248 were randomly assigned to the development cohort, while 535 were into the validation cohort. A more accurate and convenient dynamic prognostic nomogram based on age, stage, radiation, and chemotherapy was developed and validated, of which the predictive performance was superior to that of the Ann Arbor staging system [C-index:0.69 (95% CI:0.67–0.71) vs. 56 (95%CI:0.54–0.58); P < 0.001]. The 3- and 5-year AUC values of ROC curves for 3-year OS and 5-year OS in the development cohort and the validation cohort were were alll above 0.7.

Conclusion

We establish and validate a more accurate and convenient dynamic prognostic nomogram for patients with EGI DLBCL, which can provide evidence for individual treatment and follow-up.

Helicobacter pylori cagA status and gastric mucosa-associated lymphoid tissue lymphoma: a systematic review and meta-analysis

Background

Recent studies have investigated the role of Helicobacter pylori infection in the development of gastric mucosa-associated lymphoid tissue (MALT) lymphoma. It is estimated that approximately 0.1% of people infected with H. pylori develop gastric MALT lymphoma. However, the role of the CagA antigen, the highest causative agent of H. pylori, in increasing the risk of gastric MALT lymphoma remains unclear and controversial. A systematic review and meta-analysis were conducted to evaluate the effect of cagA status on the development of gastric MALT lymphoma.

Methods

All articles evaluating the status of the cagA gene in the development of gastric MALT lymphoma were collected using systematic searches in online databases, including PubMed, Scopus, Embase, and Google Scholar, regardless of publication date. The association between cagA and gastric MALT lymphoma was assessed using the odds ratio (OR) summary. In addition, a random-effects model was used in cases with significant heterogeneity.

Results

A total of 10 studies met our inclusion criteria, among which 1860 patients participated. No association between cagA status and the development of MALT lymphoma (extranodal marginal zone B-cell lymphoma) was found in this study (OR 1.30; 0.906–1.866 with 95% CIs; I²: 45.83; Q-value: 12.92). Surprisingly, a meaningful association was observed between cagA status and diffuse large B-cell lymphoma (OR 6.43; 2.45–16.84 with 95% CIs). We also observed an inverse association between vacA and gastric MALT lymphoma risk (OR 0.92; 0.57–1.50 with 95% CIs).

Conclusions

It seems that the infection with cagA-positive H. pylori strains does not have a meaningful effect on the gastric MALT lymphoma formation, while translocated CagA antigen into the B cells plays a crucial role in the development of diffuse large B-cell lymphoma.

En Bloc Resection of Primary Large Esophageal Mucosa-Associated Lymphoid Tissue Lymphoma by Endoscopic Submucosal Dissection: A Case Report

Treatment of mucosa-associated lymphoid tissue (MALT) lymphoma has recently received considerable attention. Here, we report a case of large esophageal MALT lymphoma that was successfully en bloc resected using endoscopic submucosal dissection (ESD). A 77-year-old woman was admitted to our hospital with progressive dysphagia for more than 2 months. Upper gastrointestinal endoscopy revealed a large rounded submucosal mass covered by normal mucosa, located at the lower esophagus. Endoscopic ultrasonography (EUS) showed a well-demarcated hypoechoic mass chiefly located in the esophageal wall, but the layers of the esophageal wall were not clear. ESD was performed for diagnostic and treatment purposes. No complications occurred during or after ESD. The resected specimen measured 4.3 cm × 2.8 cm × 1.5 cm. The histologic findings were diagnostic of esophageal MALT lymphoma. Infiltration of neoplastic cells in the lateral margins of the resected specimen was not observed. However, vertical margins showed an R1 situation and mild damage to the muscularis propria. After 3 months, her dysphagia disappeared. Additional radiation therapy was then administered. After 5 months, the patient was still under surveillance and free of recurrent disease. Resection with ESD of such a large mass of MALT in the esophageal region has rarely been reported before in the literature.

Primary gastric non-Hodgkin lymphomas: Recent advances regarding disease pathogenesis and treatment

Primary gastric lymphomas (PGLs) are distinct lymphoproliferative neoplasms described as heterogeneous entities clinically and molecularly. Their main histological types are diffuse large B-cell lymphoma (DLBCL) or mucosa-associated lymphoma tissue. PGL has been one of the main fields of clinical research of our group in recent years. Although gastric DLBCLs are frequent, sufficient data to guide optimal care are scarce. Until today, a multidisciplinary approach has been applied, including chemotherapy, surgery, radiotherapy or a combination of these treatments. In this minireview article, we provide an overview of the clinical manifestations, diagnosis and staging of these diseases, along with their molecular pathogenesis and the most important related clinical published series. We then discuss the scientific gaps, perils and pitfalls that exist regarding the aforementioned studies, in parallel with the unmet need for future research and comment on the proper methodology for such retrospective studies. Aiming to fill this gap, we retrospectively evaluated the trends in clinical presentation, management and outcome among 165 patients with DLBCL PGL who were seen in our institutions in 1980-2014. The study cohort was divided into two subgroups, comparing the main 2 therapeutic options [cyclophosphamide doxorubicin vincristine prednisone (CHOP) vs rituximab-CHOP (R-CHOP)]. A better outcome with immunochemotherapy (R-CHOP) was observed. In the next 2 mo, we will present the update of our study with the same basic conclusion.

Increased MALAT1 expression predicts poor prognosis in primary gastrointestinal diffuse large B-cell lymphoma

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is involved in the pathogenesis and progression of several cancers. However, the potential effect of MALAT1 in primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) has not been elucidated. This study aimed to explore the prognostic value of MALAT1 in patients with PGI-DLBCL. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the expression of MALAT1 in 90 patients with PGI-DLBCL. MALAT1 was remarkably upregulated in PGI-DLBCL tissues compared to paired adjacent non-tumor tissues (P < 0.001), and the area under the receiver operating characteristic (ROC) curve (AUC) was 0.838. MALAT1 expression was further increased in the non-germinal center B-cell-like (non-GCB), advanced stage (stages IIE-IV) and International Prognostic Index (IPI) score (3-5) groups (P = 0.01, P < 0.001 and P < 0.001, respectively). Furthermore, Kaplan-Meier analysis showed that elevated MALAT1 expression correlated with inferior overall survival (OS) and progression-free survival in PGI-DLBCL patients (P < 0.001 and P < 0.001, respectively), and our multivariate analysis results suggested that upregulation of MALAT1 and high IPI score (3-5) were two unfavorable prognostic factors for PGI-DLBCL. In conclusion, our results demonstrate that MALAT1 may serve as a novel prognostic biomarker and an ideal therapeutic target for patients with PGI-DLBCL.

Multicentric Study of Clinicopathological Features of Primary Gastrointestinal Lymphoma of Iran: from 2011 - 2016

Background: Gastrointestinal (GI) tract is the most common site for extranodal lymphoma. The primary GI lymphoma pattern in Iran is different from western countries and has been changed during the past 40 years. Objectives: This study was done to determine the clinical and pathological characteristics of primary GI lymphoma in Tehran, Hamedan, and Mashhad regions in Iran. Methods: In this cross-sectional comparative-descriptive study, 200 patients with primary GI lymphoma in Tehran, Hamadan, and Mashhad regions from 2011 to 2016 were enrolled in a consecutive manner, where the clinical and pathological characteristics of cases were determined. Results: Among 200 patients, 141 (70.5%) subjects were male and 59 (29.5%) subjects were female. The mean age at diagnosis was 54.3 ± 19.3 years. Also, 84%, 8.5%, and 7.5% of the patients’ specimens were from Tehran, Hamedan, and Mashhad, respectively. The stomach was the principal involved location in approximately half of the cases. Diffuse large B-cell lymphoma (DLBCL), was the main subtype that was observed in 64% of the cases. Treatment in 72% of cases was a combination of surgery and chemotherapy. The 5-year survival was assessed in 147 patients with a rate of 68%. Conclusions: Primary GI lymphoma is seen more in male subjects younger than 60 years of age with non-specific symptoms. Also, DLBCL and MALToma are the main histologic types, and the 5-year survival for all cases is 68.0%. The clinical symptoms showed no specific pattern and accordingly, patients with weight loss and abdominal pain should be considered in in differential diagnosis of malignant lymphoma.

Classical Hodgkin Lymphoma Presenting as a Sigmoid Mass

Primary classical Hodgkin lymphoma (CHL) in the colon is exceedingly rare and shares many histologic features with other lymphoproliferative disorders in the gastrointestinal tract. Here we report a case of CHL forming a sigmoid mass. An elderly man with a past medical history of mantle cell lymphoma presented with constipation. Imaging revealed an ulcerated, circumferential mass in the sigmoid colon. Endoscopic biopsy of the mass showed ulcerated colonic mucosa with an underlying diffuse mixed inflammatory infiltrate admixed with Hodgkin and Reed-Sternberg cells. Immunohistochemistry was performed to characterize these cells. They were weakly positive for Pax-5, strongly positive for CD30, variably positive for CD15, and negative for CD45, CD20, CD3, and SOX-11. In situ hybridization was positive for Epstein-Barr virus (EBV) and negative for cytomegalovirus or herpes simplex virus. This immunophenotype is diagnostic for CHL in the clinical context of a large mass. It is not possible in this case to determine whether this is de novo CHL or progression from a precursor lesion like EBV-positive mucocutaneous ulcer. Since diagnosis, this patient underwent colectomy followed by chemotherapy and has remained in complete remission.

A 10year cohort study of 175 primary gastrointestinal lymphoma cases in Thailand clinical features and outcomes in the immunochemotherapy era

BACKGROUND

Primary gastrointestinal lymphoma (PGIL), an uncommon subtype of lymphoma, accounts for 1%-4% of gastrointestinal cancers. This study, therefore, aimed to investigate the current 10-year epidemiology and outcomes of PGIL.

METHODS

This retrospective study involved a hospital-based chart review to analyze the epidemiology, clinical features, predisposing factors, and clinical outcomes of patients diagnosed with, and treated for, PGIL. Data covering 10 years was collected of Thai patients aged ≥ 15 years who had been diagnosed as PGIL with pathological confirmation and treated at Siriraj Hospital, Thailand.

RESULTS

A total of 175 PGIL patients were enrolled. Their median age was 60 years (range, 20-98), with a male predominance. The stomach was the most common site of gastrointestinal (GI) organ involvement by lymphoma (38.9%), followed by the small intestine (23.4%) and multiple sites of GI involvement (23.4%). Diffuse large B-cell lymphoma (DLBCL) had the highest proportion of PGIL, accounting for 61.1%. The median patient follow-up time was 13.9 months (range: 0-104.9 months). The median overall survival (OS) of PGIL patients was not reached during the 10 years, with a 5-year OS of 64.4%. The probability of having a better OS was demonstrated in patients with a good performance status who received a rituximab-containing regimen.

CONCLUSIONS

The stomach was the most common site of lymphoma involvement in the GI tract, with DLBCL accounting for the highest proportion of those patients. The long-term survival outcome was significantly improved in patients with good performance status and rituximab exposure. Trial registrationNot applicable.

Surgery shows survival benefit in patients with primary intestinal diffuse large B-cell lymphoma: A population-based study

BACKGROUND

The clinical characteristics and prognosis of primary intestinal diffuse large B-cell lymphoma (PI-DLBCL) are rarely reported. We aimed to explore the role of surgery in patients with PI-DLBCL.

METHODS

Adult PI-DLBCL patients were included from the Surveillance, Epidemiology, and End Results database. The effect of surgery was evaluated by Kaplan-Meier and Cox proportional regression analyses. Propensity score matching (PSM) was used to reinforce our results. Lasso regression was utilized to determine independent risk factors of overall survival (OS) for a nomogram and a novel web-based calculator. The performance of the model was measured via concordance index, receiver operating characteristic curve, and calibration plots in both cohorts.

RESULTS

Overall, 1602 patients with PI-DLBCL were analyzed. Surgery significantly improved survival in both univariate and multivariate analyses (p = 0.007, p < 0.001, respectively). Before PSM, local tumor destruction (LTD) displayed a survival advantage over resection in patients without chemotherapy (p = 0.034). After PSM, surgery was still identified as a beneficial factor for OS (p = 0.0015). However, there was no statistical difference between LTD and resection (p = 0.32). The nomogram for 3-, 5-, and 10-year OS predictions exhibited dependable consistency between internal and external validation.

CONCLUSION

This study approves the beneficial effect of surgery on clinical endpoints in PI-DLBCL patients. For those who are not suitable for resection, LTD may also be a practical option. The predictive nomogram and the web-based calculator could help clinicians individually evaluate the prognosis and optimize personalized treatment decisions for these patients.

Molecular Pathogenesis of Primary Gastrointestinal Tract Lymphomas

Primary gastrointestinal lymphomas are rare though the incidence is significantly increased among adult patients in recent years. The majority of the patients present with symptoms overlapping with other gastrointestinal disorders and imaging findings are not specific. Therefore, histologic examination is necessary to establish the diagnosis. Insight into etiologies, molecular pathogenesis and critical signaling pathways in lymphomas including gastrointestinal lymphomas has significantly expanded within the last 3 decades. Given the increasing demand for incorporation of genetic data, the appropriate handling and processing of small endoscopic gastrointestinal biopsy samples of suspected lymphoma is becoming extremely crucial and at times challenging. The use of next generation sequencing with analysis of genes relevant to diagnosis, prognosis, and therapeutic targets continues to have a significant promising impact on management of patients in lymphoid malignancies. In particular, the identification of constitutively activated pathways and the emergence of novel targeted medications predict that more effective therapies will be identified for these disorders in the coming years.

Gastrointestinal Tract Lymphomas: A Review of the Most Commonly Encountered Lymphomas

CONTEXT.—

The gastrointestinal (GI) tract is the most common site of extranodal non-Hodgkin lymphoma, accounting for 20% to 40% of all extranodal lymphomas. The majority of these are systemic processes secondarily involving the GI tract. Primary GI lymphomas are less common, accounting for approximately 10% to 15% of all non-Hodgkin lymphoma. Most non-Hodgkin lymphoma involving the GI tract are of B-cell lineage, of which diffuse large B-cell lymphoma is the most common subtype, irrespective of location.

OBJECTIVE.—

To review the lymphoproliferative neoplasms of B-cell and T-cell lineage involving the luminal GI tract according to the most prevalent subtypes at each anatomic site.

DATA SOURCE.—

Systematic search of the PubMed database for updated literature on GI lymphomas epidemiology, subtypes, clinical, endoscopic, and genetic findings. Histologic images are derived from our collection of clinical cases.

CONCLUSIONS.—

The GI tract is the most common site of extranodal lymphoproliferative neoplasms. Recognition of the most frequently encountered GI lymphomas is imperative for patient management and treatment.

Risk and survival of second primary malignancies following diagnosis of gastric mucosa-associated lymphoid tissue lymphomas: A population-based study

Whether gastric mucosa-associated lymphoid tissue lymphoma (GML) is associated with a higher risk of second primary malignancy (SPM) remains controversial. This study aimed to evaluate the detailed risk of SPM and its prognosis in patients with GML based on a large population-based cohort. The Surveillance, Epidemiology, and End Results database was searched to identify patients who were diagnosed with GML during 2000-2014. The standardized incidence ratio was used to estimate the relative risk of developing SPM. Overall survival was evaluated using the Kaplan-Meier method with the log-rank test, as well as Cox regression analysis. Among 3,379 patients with GML, 416 patients (12.31%) developed SPMs. Compared to the general US population, GML patients had a significantly increased risk of developing SPM (standardized incidence ratio: 1.46, 95% CI: 1.33-1.61). The SPM sites were stomach, lung and bronchus, small intestine, thyroid, mouth, and non-Hodgkin's lymphoma. The risk of developing SPM in GML patients varied according to clinical and demographic characteristics. Patients with younger age (<50 year), chemotherapy use and radiotherapy use had the higher risk of developing SPMs. Relative to patients with only GML, GML patients who developed the SPMs had significantly poorer overall survival (P < 0.001). Among GML patients with SPMs, poor overall survival was independently associated with non-localized SPM disease, shorter latency period (<60 months), chemotherapy use and older age (≥70 year). Patients with GML had an elevated risk of developing SPM, which was associated with a poor prognosis. These findings may be useful for improving follow-up surveillance for patients with GML.

Hematologic malignancies of the gastrointestinal luminal tract

Hematologic malignancies include several lymphoproliferative and myeloproliferative disorders, many of which are frequently encountered in current health care settings. These malignancies frequently affect the gastrointestinal (GI) tract, either by secondary extranodal or extramedullary extension to the GI tract, or as a primary process arising in the GI tract. In fact, the GI tract may represent the most common extranodal site of involvement in many of them, such as lymphoma. Furthermore, in the current era of improved cancer treatment and advanced transplant procedures with increased survival, it has been quite common to encounter GI involvement by these malignancies through the disease course. Post-transplant lymphoproliferative disorder following kidney transplantation, for example, very commonly involves the GI tract. Other conditions that can involve the GI tract include multiple myeloma, plasmacytoma, myeloid sarcoma, mastocytosis, and Castleman disease. Imaging diagnosis of these malignancies can be challenging, since they are much less common than primary GI cancers and both share many common imaging features as well. However, certain imaging features, particularly in combination with a matching clinical scenario, play a pivotal role in diagnosing these conditions and directing further evaluation. In this article, we review common and rare hematologic malignancies of the GI tract and discuss their pathophysiologic, clinical, and imaging features.

Monomorphic Epitheliotropic Intestinal T-cell Lymphoma of the Stomach: Two Case Reports and a Literature Review

We describe the clinicopathologic and molecular features of 2 cases of gastric monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), which were first diagnosed from gastric biopsies, one was primary whereas the other was gastric involvement by MEITL. Both cases were older men with stomach ulcers. Case 1 was admitted for a hemorrhage in the upper digestive tract and case 2 for edema. Histology of both cases showed infiltrated monomorphic and medium-sized lymphocytes with lymphoid epithelial phenomenon. An inflammatory background and vascular hyperplasia were also observed likely due to the ulceration. Neoplastic cells expressed CD2, CD3, CD7, CD8, CD56, TIA-1, and MYC, not CD5, CD4, Granzyme B, CD20, CD30, TdT, or EBER. Both lymphomas showed TCRG gene rearrangement and c-MYC gains. Moreover, we first affirmed polysomy of chromosome 8 in case 2. For correct diagnosis of this rare tumor at the rare location, it is important that pathologists raise the possibility and exclude other differential diagnoses.

Texture Analysis Improves the Value of Pretreatment 18F-FDG PET/CT in Predicting Interim Response of Primary Gastrointestinal Diffuse Large B-Cell Lymphoma

Objectives

To explore the application of pretreatment 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) texture analysis (TA) in predicting the interim response of primary gastrointestinal diffuse large B-cell lymphoma (PGIL-DLBCL).

Methods

Pretreatment 18F-FDG PET/CT images of 30 PGIL-DLBCL patients were studied retrospectively. The interim response was evaluated after 3-4 cycles of chemotherapy. The complete response (CR) rates in patients with different clinicopathological characteristics were compared by Fisher's exact test. The differences in the maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and texture features between the CR and non-CR groups were compared by the Mann-Whitney U test. Feature selection was performed according to the results of the Mann-Whitney U test and feature categories. The predictive efficacies of the SUVmax, MTV, and the selected texture features were assessed by receiver operating characteristic (ROC) analysis. A prediction probability was generated by binary logistic regression analysis.

Results

The SUVmax, MTV, some first-order texture features, volume, and entropy were significantly higher in the non-CR group. The energy was significantly lower in the non-CR group. The SUVmax, volume, and entropy were excellent predictors of the interim response, and the areas under the curves (AUCs) were 0.850, 0.805, and 0.800, respectively. The CR rate was significantly lower in patients with intestinal involvement. The prediction probability generated from the combination of the SUVmax, entropy, volume, and intestinal involvement had a higher AUC (0.915) than all single parameters.

Conclusions

TA has potential in improving the value of pretreatment PET/CT in predicting the interim response of PGIL-DLBCL. However, prospective studies with large sample sizes and validation analyses are needed to confirm the current results.

Overexpression of microRNA-130a predicts adverse prognosis of primary gastrointestinal diffuse large B-cell lymphoma

Primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) is a highly heterogeneous type of non-Hodgkin lymphoma. A number of studies have demonstrated that microRNA-130a (miR-130a) serves a role in the tumorigenesis and prognosis of numerous human tumors. However, to the best of our knowledge, the prognostic significance of miR-130a in PGI-DLBCL remains unknown. The present study explored the association between miR-130a and the clinical outcomes of PGI-DLBCL. Relative miR-130a expression was assessed by reverse transcription-quantitative PCR. Immunohistochemistry was used to detect expression levels of BCL-2, c-MYC, neprilysin, B-cell lymphoma 6 protein, PWWP domain-containing DNA repair factor 3A and proliferation marker protein Ki-67. A receiver operating characteristic curve was constructed to analyze the specificity and sensitivity of microRNA levels in the diagnosis of PGI-DLBCL. Survival curves were constructed using the Kaplan-Meier method. In the present study, miR-130a expression was notably higher in patients with PGI-DLBCL compared with in the controls (P<0.0001). miR-130a overexpression was closely associated with a high International Prognostic Index score (3–5) and drug resistance (P=0.017 and P=0.044, respectively). No significant difference in other clinical features was observed. Patients with increased expression levels of miR-130a had lower overall survival [hazard ratio (HR), 2.998; 95% CI, 1.347-6.673; P=0.007] and progression-free survival (HR, 3.325; 95% CI, 1.488-7.429; P=0.003) compared with patients who had lower expression levels of miR-130a. Furthermore, multivariate Cox regression analysis suggested that miR-130a was a negative prognostic parameter in PGI-DLBCL. Therefore, upregulation of miR-130a could become a potential prognostic marker for PGI-DLBCL. Additionally, further study of these results may have important guiding significance for the prognosis of patients with PGI-DLBCL in the clinical setting.

Mycosis fungoides and gastric T-cell lymphoma: A case report

Mycosis fungoides (MF) is a cutaneous malignant lymphoma with an extended clinical course. MF presents in series of dermatological manifestations, beginning with patches and plaques of the skin, and eventually evolving into tumours. Often MF can occur for extended periods without worsening of external symptoms, while the disease advances internally in organs such as lymph nodes, liver, spleen, lung, bone marrow, gastrointestinal tract, pancreas and kidney. The present report presents a clinical case in which gastrointestinal symptomatology occurred a decade after the first dermatological manifestation. Immunohistochemical analysis of the skin, along with small bowel biopsies revealed evidence of gastric T-cell lymphoma. To the best of our knowledge, the present study is the first to describe such a case in the literature.

Nomogram for Predicting the Overall Survival of Adult Patients With Primary Gastrointestinal Diffuse Large B Cell Lymphoma: A SEER- Based Study

Background: The aim of this study was to establish a precise prognostic model, based on significant clinical parameters, for predicting the overall survival (OS) of adult patients with primary gastrointestinal diffuse large B cell lymphoma (GI DLBCL).

Materials and Methods: The data of 7,121 GI DLBCL patients, diagnosed between 1997 and 2015, were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. These patients were randomly divided into two sequential cohorts: training (n = 5,697) set and validation (n = 1,424) set. ROC methodology and calibration curves were explicitly used to evaluate the predictive performance of nomogram.

Results: The median OS in the training cohort was 76 months (1–239 months), and 3, 5, and 10-year OS rates were 60.3, 53.9, and 39.5%, respectively. Age at diagnosis, Ann Arbor stage, and marital status were important clinical predictors of OS. These characteristics were used to build a nomogram. The AUC of the nomogram for predicting 3, 5, and 10-year OS were 0.669, 0.692, and 0.740, respectively. All RUC and calibration curves revealed good accuracy in predicting prognosis of GI DLBCL.

Conclusion: In summary, the established nomogram was validated to predict OS for adult patients with GI DLBCL. This predictive model could help clinicians identify high-risk patients to improve their prognosis.

miR-150 is a negative independent prognostic biomarker for primary gastrointestinal diffuse large B-cell lymphoma

A number of studies suggest an association between miRNAs and diffuse large B-cell lymphoma (DLBCL). The present study aimed to investigate the prognostic value of microRNA (miR-150) in primary gastrointestinal (PGI)-DLBCL, by assessing the association between miR-150 expression and clinicopathological characteristics in patients with PGI-DLBCL. A total of 84 patients diagnosed with PGI-DLBCL were recruited and both tumor and adjacent non-tumor tissue samples were collected. miR-150 expression was assessed via reverse transcription-quantitative (RT-q)PCR analysis. The results demonstrated that miR-150 expression was significantly lower in PGI-DLBCL tissues compared with adjacent non-tumor tissues. Furthermore, receiver operating characteristic (ROC) curve analysis indicated that the optimal cut-off value of miR-150 for predicting survival was 8.965 with high sensitivity (79.8%) and specificity (77.1%). Patients were divided into two groups according to this cut-off value, as follows: High (n=18) and low expression (n=66) groups. Low miR-150 expression was significantly associated with clinical stage, International Prognostic Index (IPI), Eastern Cooperative Oncology Group status and use of rituximab. RT-qPCR analysis demonstrated that miR-150 expression was significantly lower in patients with high IPI scores compared with patients with low IPI scores. Downregulated miR-150 expression was significantly associated with shorter overall survival (OS) time and progression-free survival (PFS) time in patients with PGI-DLBCL. Furthermore, miR-150 level and IPI score were identified as two risk factors for OS and PFS. The diagnostic value of miR-150 was evaluated via ROC curve analysis, with an area under the curve value of 0.882. Taken together, the results of the present study suggest that miR-150 is a potential diagnostic marker of PGI-DLBCL, and may also serve as a useful prognostic factor for survival outcomes in patients with PGI-DLBCL.

Practical Approach to the Histologic Diagnosis of Gastrointestinal Lymphomas Through the First-line Marker Battery of CD20, CD3, CD30, and Epstein-Barr Virus-encoded RNAs

The gastrointestinal (GI) tract is a prevalent site for extranodal lymphomas. Some subtypes of GI tract lymphomas are aggressive and have dismal clinical outcomes. Therefore, prompt histopathologic detection of such types can be very important. We thus introduce a practical approach in the histopathologic diagnosis of GI lymphomas according to the revised World Health Organization (WHO) classification. When lymphocyte proliferation is found in the GI tract, a stepwise approach can help narrow down the differential diagnoses. When considering subtype incidence, macroscopic findings, and microscopic patterns, applying a first-line marker battery of CD20, CD3, CD30, and Epstein-Barr virus-encoded RNAs can effectively narrow down the top differential diagnoses at the initial step. Generally, the most common subtype among GI tract lymphomas is B-cell non-Hodgkin lymphoma identified by CD20 expression, followed by T-cell and NK-cell non-Hodgkin lymphomas identified by the CD3 expression, and some subtypes are defined by Epstein-Barr virus infection or CD30 expression. Macroscopically, lymphomas present as various gross types, such as large masses, small lesions, superficial and shallow lesions, polyp-like or polyposis-like features, or ulcer/necrosis/perforation. Microscopically, large pleomorphic cells or small to medium-sized tumor cells grow with various architectures and tumor microenvironments. Incorporation of macroscopic and microscopic features and the stepwise immunophenotyping may be a practical approach to the differential diagnosis of aggressive lymphoma, indolent/low-grade lymphoma, or benign to indolent lymphoproliferative disease. Exceptions always exist; this approach focuses on the relatively prevalent circumstances of lymphomatous lesions initially encountered in the GI tract.

Gastrointestinal lymphoma: the new mimic

Background

Gastrointestinal (GI) lymphomas comprise a group of distinct clinicopathological entities of B- or T- cell type, with primary gastrointestinal Hodgkin lymphoma being extremely uncommon. The GI tract is the predominant site of extranodal non-Hodgkin lymphoma accounting for 30–40% of all extranodal lymphomas. In the Western world, the stomach is the most commonly involved site followed by the small bowel. Several chronic inflammatory and immune-mediated disorders which predispose to accelerated cell turnover may lead to the malignant transformation of gut lymphocytes and ultimately manifest as GI lymphoma. The challenge for the clinical gastroenterologist is that these tumors may have varied presentations, ranging from nonspecific symptoms such as dyspepsia or bloating to abdominal pain, nausea, vomiting, GI bleeding, diarrhea, weight loss or bowel obstruction.

Objective

We illustrate the range of presentations of GI lymphoma with examples based on consecutive cases evaluated at our institution over a 6-month period. These cases demonstrate how appropriately directed endoscopic evaluation with biopsies has the potential to provide a definitive diagnosis and allow the patient to proceed to definitive therapy.

Conclusions

The GI tract is the most commonly involved site for extranodal lymphoma with the stomach being most frequently involved organ. Chronic Helicobacter pylori infection, celiac disease, inflammatory bowel disease and autoimmune disorders may predispose to GI lymphoma. This heterogenous group of diseases has varied presentations that may mimic several other GI clinico-pathologic entities. GI lymphomas may be diagnosed with appropriately directed endoscopic evaluation coupled with generous tissue sampling and expert pathologic assessment. Management may range from antibiotic therapy, in the case of Helicobacter pylori-associated gastric MALT lymphoma, to chemotherapy with or without radiation and, in rare instances, surgery. There are presently no guidelines to direct endoscopic surveillance of GI lymphomas following treatment.

TLR4 expression correlated with PD-L1 expression indicates a poor prognosis in patients with peripheral T-cell lymphomas

Background: Toll-like receptor 4 (TLR4), a member of the pattern recognition receptors, has been reported to be involved in carcinogenesis. However, the clinical impact of TLR4 in peripheral T-cell lymphomas (PTCL) remains unclear.

Methods: The current study, using immunohistochemical staining, first examined TLR4 and programmed cell death-ligand 1 (PD-L1) expression in patients with PTCL, to correlate TLR4 and PD-L1 expression with clinicopathological parameters.

Results: It was found that the rates of high expression of TLR4 and PD-L1 were 41.7% and 45.8%, respectively. TLR4 expression was closely associated with PD-L1 expression. The expression of TLR4 was closely related to primary extranodal site involvement, increased Ann Arbor stage, and low hemoglobin expression, while the expression of PD-L1 was closely related to a low platelet count and multiple extranodal organ involvements (>1). High expression of either TLR4 or PD-L1 indicated a poor survival rate for patients with PTCL. Multivariate analyses further confirmed that increased expression levels of TLR4 and PD-L1 are unfavorable prognostic factors for PTCL.

Conclusion: This study demonstrates that the expressions of TLR4 and PD-L1 are independent predictors of survival time for patients with PTCL. Thus, TLR4 and PD-L1 may serve as potential therapeutic targets in PTCL patients.

Early Onset Multiple Primary Tumors in Atypical Presentation of Cowden Syndrome Identified by Whole-Exome-Sequencing

A family with an aggregation of rare early onset multiple primary tumors has been managed in our oncogenetics department: the proband developed four early onset carcinomas between ages 31 and 33 years, including acral melanoma, bilateral clear cell renal carcinoma (RC), and follicular variant of papillary thyroid carcinoma. The proband's parent developed orbital lymphoma and small intestine mucosa-associated lymphoid tissue (MALT) lymphoma between 40 and 50 years old. Whole-exome-sequencing (WES) of the nuclear family (proband, parents, and sibling) identified in the proband a de novo deleterious heterozygous mutation c.1003C > T (p.Arg335^∗) in the phosphatase and tensin homolog (PTEN) gene. Furthermore, WES allowed analysis of the nuclear family's genetic background, and identified deleterious variants in two candidate modifier genes: CEACAM1 and MIB2. CEACAM1, a tumor suppressor gene, presents loss of expression in clear cell RC and is involved in proliferation of B cells. It could explain in part the phenotype of proband's parent and the occurrence of clear cell RC in the proband. Deleterious mutations in the MIB2 gene are associated with melanoma invasion, and could explain the occurrence of melanoma in the proband. Cowden syndrome is a hereditary autosomal dominant disorder associated with increased risk of muco-cutaneous features, hamartomatous tumors, and cancer. This atypical presentation, including absence of muco-cutaneous lesions, four primary early onset tumors and bilateral clear cell RC, has not been described before. This encourages including the PTEN gene in panel testing in the context of early onset RC, whatever the histological subtype. Further studies are required to determine the implication of CEACAM1 and MIB2 in the severity of Cowden syndrome in our proband and occurrence of early onset MALT lymphoma in a parent.

Synchronous diffuse large B-cell lymphoma of the stomach and small cell lung carcinoma: A case report

RATIONALE

The synchronous occurrence of lung cancer in patients with gastric neoplasms is relatively uncommon, especially the cases of synchronous coexistence of small cell lung carcinoma and diffuse large B-cell lymphoma of the stomach.

PATIENT CONCERNS

We encountered a case of synchronous primary small cell lung carcinoma and diffuse large B-cell lymphoma of the stomach. A 63-year-old patient with a 7.5 × 5.09 cm mass in the superior lobe of the right lung diagnosed with small cell lung cancer and synchronous diffuse large B-cell lymphoma of the stomach.

DIAGNOSES

The diseases were diagnosed by the pathological biopsy and immunohistochemical methods.

INTERVENTIONS

As the patient received CHOP chemotherapy, pulmonary function deterioraed. Etoposide was added to the chemotherapy.

OUTCOMES

However, after the first treatment, chest computed tomography showed that the mass in the superior lobe of the right lung had increased to 8.5 × 5.2 cm.

LESSONS

This report draws attention to the fact that the treatment of synchronous tumors is a challenge.

Spectrum of CT Findings in Thoracic Extranodal Non-Hodgkin Lymphoma

Non-Hodgkin lymphoma (NHL) frequently manifests in extranodal structures in the chest, often in the form of secondary involvement but occasionally as primary disease. Because staging and treatment are affected by the presence of extranodal disease at imaging, radiologists' interpretation and management of suspicious findings are critical to patient care. Unfortunately, owing to considerable imaging overlap with other diseases, primary extranodal lymphoma is difficult to diagnose with imaging alone. Radiologists should have a heightened degree of suspicion in patients at risk (including patients with immune compromise, autoimmune diseases, or a history of stem cell or solid organ transplant) or with particular imaging appearances (including the vertebral wraparound sign, nonresolving consolidation, an infiltrative soft-tissue mass, and lesions demonstrating vascular encasement without invasion). For patients with known NHL, positron emission tomography/computed tomography (PET/CT) using fluorine 18 (¹⁸F)-labeled fluorodeoxyglucose (FDG) is now preferred for routine staging in most cases. CT remains heavily used, and identification of subtle extranodal involvement with CT can be improved with use of intravenous contrast material and careful review of multiplanar images. Pericardial effusion, pleural soft tissue (even when mild), mass-like consolidation, perilymphatic nodularity, and new lytic bone lesions are particularly suggestive of secondary involvement in a patient with known NHL. Magnetic resonance imaging is a helpful problem-solving tool when equivocal findings would change staging and treatment. This comprehensive review illustrates the spectrum of CT manifestations of extranodal NHL in the chest, including the pleura, lung, airways, heart, pericardium, esophagus, chest wall, and breast. ^©RSNA, 2017.

Potential model for differential diagnosis between Crohn's disease and primary intestinal lymphoma

AIM

To evaluate the usefulness of different parameters to differentiate Crohn’s disease (CD) from primary intestinal lymphoma (PIL).

METHODS

The medical records of 85 patients with CD and 56 patients with PIL were reviewed retrospectively. Demographic, clinical, laboratory, endoscopic, and computed tomographic enterography (CTE) parameters were collected. The univariate value of each parameter was analyzed. A differentiation model was established by pooling all the valuable parameters. Diagnostic efficacy was analyzed, and a receiver operating characteristic (ROC) curve was plotted.

RESULTS

The demographic and clinical parameters that showed significant values for differentiating CD from PIL included age of onset, symptom duration, presence of diarrhea, abdominal mass, and perianal lesions (P < 0.05). Elevated lactate dehydrogenase and serum β2-microglobulin levels suggested a PIL diagnosis (P < 0.05). The endoscopic parameters that showed significant values for differentiating CD from PIL included multiple-site lesions, longitudinal ulcer, irregular ulcer, and intraluminal proliferative mass (P < 0.05). The CTE parameters that were useful in the identification of the two conditions included involvement of ≤ 3 segments, circular thickening of the bowel wall, wall thickness > 8 mm, aneurysmal dilation, stricture with proximal dilation, “comb sign”, mass showing the “sandwich sign”, and intussusceptions (P < 0.05). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the differentiation model were 91.8%, 96.4%, 93.6%, 97.5%, and 88.5%, respectively. The cutoff value was 0.5. The area under the ROC curve was 0.989.

CONCLUSION

The differentiation model that integrated the various parameters together may yield a high diagnostic efficacy in the differential diagnosis between CD and PIL.

Prevalence of clarithromycin-resistant Helicobacter pylori strains in gastric mucosa-associated lymphoid tissue lymphoma patients

Gastric MALT lymphoma is closely associated with Helicobacter pylori infection. Bacterial eradication therapy comprising clarithromycin is the first-line treatment in gastric MALT lymphoma patients. However, antimicrobial resistance to clarithromycin has been increasing in Europe, and thus far, it has not been examined in gastric MALT lymphoma patients. Based upon histopathological investigation, 17 adult gastric MALT lymphoma patients were identified to be related with H. pylori infection between 1997 and 2014. Detection of H. pylori infection in these patients and clarithromycin susceptibility testing were performed by 23S rRNA gene real-time PCR. Twelve of the patients were confirmed with H. pylori infection by real-time PCR. Among these patients, only two were found to be infected with clarithromycin-resistant H. pylori strain. In one of them, both the clarithromycin-resistant and sensitive genotype were detected. The rate of clarithromycin resistance was 15.4 %. Clarithromycin resistance pattern in gastric MALT lymphoma patients is under the predictions since a previous study performed in Central Europe revealed a rate of 36.6 % in Austria. Considering the low antimicrobial resistance rate, clarithromycin is still an option in gastric MALT lymphoma management.

Radiological Features of Gastrointestinal Lymphoma

Gastrointestinal lymphomas represent 5–20% of extranodal lymphomas and mainly occur in the stomach and small intestine. Clinical findings are not specific, thus often determining a delay in the diagnosis. Imaging features at conventional and cross-sectional imaging must be known by the radiologist since he/she plays a pivotal role in the diagnosis and disease assessment, thus assisting in the choice of the optimal treatment to patients. This review focuses on the wide variety of imaging presentation of esophageal, gastric, and small and large bowel lymphoma presenting their main imaging appearances at conventional and cross-sectional imaging, mainly focusing on computed tomography and magnetic resonance, helping in the choice of the best imaging technique for the disease characterization and assessment and the recognition of potential complications.