A Transfer Learning Radiomics Nomogram for Preoperative Prediction of Borrmann Type IV Gastric Cancer From Primary Gastric Lymphoma

ObjectiveThis study aims to differentiate preoperative Borrmann type IV gastric cancer (GC) from primary gastric lymphoma (PGL) by transfer learning radiomics nomogram (TLRN) with whole slide images of GC as source domain data.Materials and MethodsThis study retrospectively enrolled 438 patients with histopathologic diagnoses of Borrmann type IV GC and PGL. They received CT examinations from three hospitals. Quantitative transfer learning features were extracted by the proposed transfer learning radiopathomic network and used to construct transfer learning radiomics signatures (TLRS). A TLRN, which integrates TLRS, clinical factors, and CT subjective findings, was developed by multivariate logistic regression. The diagnostic TLRN performance was assessed by clinical usefulness in the independent validation set.ResultsThe TLRN was built by TLRS and a high enhanced serosa sign, which showed good agreement by the calibration curve. The TLRN performance was superior to the clinical model and TLRS. Its areas under the curve (AUC) were 0.958 (95% confidence interval [CI], 0.883–0.991), 0.867 (95% CI, 0.794–0.922), and 0.921 (95% CI, 0.860–0.960) in the internal and two external validation cohorts, respectively. Decision curve analysis (DCA) showed that the TLRN was better than any other model. TLRN has potential generalization ability, as shown in the stratification analysis.ConclusionsThe proposed TLRN based on gastric WSIs may help preoperatively differentiate PGL from Borrmann type IV GC.Borrmann type IV gastric cancer, primary gastric lymphoma, transfer learning, whole slide image, deep learning.

Helicobacter pylori virulence factors: relationship between genetic variability and phylogeographic origin

Background Helicobacter pylori is a pathogenic bacteria that colonize the gastrointestinal tract from human stomachs and causes diseases including gastritis, peptic ulcers, gastric lymphoma (MALT), and gastric cancer, with a higher prevalence in developing countries. Its high genetic diversity among strains is caused by a high mutation rate, observing virulence factors (VFs) variations in different geographic lineages. This study aimed to postulate the genetic variability associated with virulence factors present in the Helicobacter pylori strains, to identify the relationship of these genes with their phylogeographic origin. Methods The complete genomes of 135 strains available in NCBI, from different population origins, were analyzed using bioinformatics tools, identifying a high rate; as well as reorganization events in 87 virulence factor genes, divided into seven functional groups, to determine changes in position, number of copies, nucleotide identity and size, contrasting them with their geographical lineage and pathogenic phenotype. Results Bioinformatics analyses show a high rate of gene annotation errors in VF. Analysis of genetic variability of VFs shown that there is not a direct relationship between the reorganization and geographic lineage. However, regarding the pathogenic phenotype demonstrated in the analysis of many copies, size, and similarity when dividing the strains that possess and not the cag pathogenicity island (cagPAI), having a higher risk of developing gastritis and peptic ulcer was evidenced. Our data has shown that the analysis of the overall genetic variability of all VFs present in each strain of H. pylori is key information in understanding its pathogenic behavior.

Gastric lymphoma with perforation contained by an abscess and endothoracic extension

Resumen Mujer de 46 años que consulta por epigastralgia, hematemesis y melenas. Antecedente reciente de consumo de AINES (aintiiflamatorios no esteroideos). Se realiza endoscopia alta objetivando úlcera de aspecto excavado rodeada por pliegues engrosados que parece continuar con una cavidad e impresiona de perforación. Se solicita tomografía computarizada toracoabdominal confirmando la perforación, que está contenida por absceso infradiafragmático con signos de extensión endotorácica. El estudio histológico de las biopsias gástricas concluye linfoma B difuso de células grandes fenotipo no centrogerminal y subtipo inmunoblástico. Los linfomas representan menos del 5% de los tumores del tracto gastrointestinal, afectando fundamentalmente al estómago. La perforación gástrica ocurre ocasionalmente en pacientes en tratamiento con quimioterapia. Sin embargo, la perforación espontánea es rara, y supone un factor de mal pronóstico además de tener elevada mortalidad.

18F-fluorodeoxyglucose Positron Emission Tomography/computed Tomography Comparison of Gastric Lymphoma and Gastric Carcinoma

ObjectiveThis study aimed to compare the characteristics of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in gastric lymphoma (GL) and gastric carcinoma (GC).METHODSPatients with newly diagnosed GL or GC who underwent 18F-FDG PET/CT prior to treatment were included in this study. The PET/CT features of gastric wall lesions, including FDG avidity, pattern, and intensity [maximal standard uptake value (SUVmax)] were reviewed and analyzed. The correlation of SUVmax with gastric clinicopathological variables was investigated by Student’s t test, Mann-Whitney U test, chi-square test, and receiver-operating characteristic (ROC) curve analysis to determine the differential diagnostic value of SUVmax-associated parameters in GL and GC.RESULTSA total of 68 patients with GL and 117 with GC were included in this study. Abnormal gastric FDG accumulation was found in 66 (97.05%) patients with GL and 109 (93.16%) patients with GC. Majority of the GL patients presented with type I and III lesions, whereas GC patients mainly with type II and III lesions. The SUVmax [14.89(6.56，22.12) vs 4.08(5.75，10.24), P<0.001) and SUVmax/THKmax (maximal thickness) [0.72(0.50,1,10) vs 0.39(0.28,0.64), P<0.000] were both higher in patients with GL when compared with GC. The SUVmax was higher in GL patients with DLBCL than in those with MALT (17.51±10.31 vs 4.97±2.92, P =0.0010) and higher in patients with advanced Lugano stage (II1/II2/IV) than in those with stage I (18.27±10.19 vs 9.92±9.22, P = 0.002). In GC patients, the SUVmax was higher in T3+T4 than in T1+T2 [6.79(4.47,12.41) vs 4.09(2.32,6.31), P = 0.000], but there were no significant differences between TNM stage I+II and TNM stage III+IV. The ROC curve analysis suggested a better performance of SUVmax/THKmax in evaluating gastric lesions between GL and GC when compared to SUVmax alone. The sensitivity of SUVmax and SUVmax/THKmax for differential diagnosis of GL and GC were 0.917 and 0.578, respectively. However, the specificity of SUVmax/THKmax for differential diagnosis of GL and GC was higher than that of SUVmax alone (0.894 VS 0.485).CONCLUSIONThe PET/CT features differed between GL and GC, and these can improve the evaluation of PET/CT of gastric wall lesions and help differentiate GL from GC.

An Overview of Surgical Treatment of Perforated Peptic Ulcer

A number of advancements in the therapy of perforated duodenal ulcers have been made in the recent two decades, suggesting that the disease's morbidity and mortality may be reduced. Recently, there has been a return to a more conservative first approach, with reports of either delayed resection or two-stage surgery, in which a non-radical resection is performed first, followed by lymphadenectomy at a later date. Furthermore, because gastric lymphoma can be cured without resection, many upper GI surgeons recommend performing a biopsy and repair at the index operation and then considering how best to continue if adenocarcinoma is discovered later.

Diagnosing MALT Gastric Lymphoma in Gastroenterologist’s Practice, a Clinical Observation

Aim. A clinical case description to highlight challenges in diagnosing MALT lymphoma presented in infiltrative ulcer-ative lesions.Key points. A 60-yo patient was admitted to the Loginov Moscow Clinical Scientific Centre with epigastric pain and an 18 kg weight loss over past 4 months. A history of repeated outpatient endoscopic examinations revealing subse-quently ulcerative and infiltrative ulcerative gastric lesions of unestablished origin. A complex examination combin-ing oesophagogastroduodenoscopy (OGDS), endosonography (EUS), multislice computed tomography (MSCT), morphological and immunohistochemical (IHC) assays elicited the MALT gastric lymphoma IIE stage involving para-gastric and intraperitoneal lymph nodes. The first treatment stage included line-1 eradication therapy, rabeprazole 20 mg x 2 times a day, amoxicillin 1000 mg x 2 times a day, clarithromycin 500 mg x 2 times a day, bismuth tripotas-sium dicitrate 240 mg x 2 times a day — for 14 days. Accounting for the process prevalence and stage, six courses of R-CHOP polychemotherapy (PCT) were ordered by haematologist.Conclusion. This observation demonstrates a targeted-biopsy endoscopic examination followed by morphological, IHC, EUS (for invasion depth) and MSCT (for process advancement) assays to be decisive in differential diagnosis of ulcerative and infiltrative ulcerative gastric lesions.