Inflammatory myofibroblastic tumors (IMTs) are mesenchymal tumors of intermediate malignant potential. Gastric IMTs are rare and commonly affect young adults. They are typically confused with gastrointestinal stromal tumors, inflammatory fibroid polyps, and leiomyosarcomas. The etiology of IMTs remains unclear, but is theorized to be due to hyperinflammatory response to chronic infections. We present a middle-aged woman found to have a gastric mass positive for Helicobacter pylori, underwent multiple endoscopies with endoscopic ultrasound, and a definitive diagnosis of gastric IMT was only made after a partial gastrectomy with immunohistochemistry negative for CD-117, S-100, ALK-1, and positive for vimentin and SMA.

UNASSIGNED: Gastric liposarcoma (GL) is extremely rare and radical surgery has been the conventional treatment, even in small tumors. Laparoscopic wedge resection has been reported worldwide for subepithelial tumors of the stomach.
UNASSIGNED: The patient was an asymptomatic 63-year-old man presenting with a subepithelial gastric tumor. The esophagogastroduodenoscopy showed a 3 cm ulcerated soft tumor located in the posterior wall of the antrum just above the pylorus. Two preoperative biopsies were performed with a negative result for malignant neoplasm. Dynamic computerized tomography revealed 35 × 35 mm well-defined pyloric mass with fat density. Despite the difficult location of the tumor, function-preserving surgery was performed. Surgery was initiated by a laparoscopic approach with four trocars. After the dissection of the greater omentum, the greater curvature and the posterior wall of the stomach were exposed. A gastrostomy was performed in the anterior wall of the antrum. Due to the difficulty in identifying the tumor location, a mini-laparotomy was conducted. After assessing the pylorus and section parameters, the tumor was extracted by gastrostomy and resected with a linear stapler. The patient was discharged after five days with no complications. The histological diagnosis was a well-differentiated liposarcoma. Resection margins were clear. The tumor cells tested negative for MDM2. No adjuvant therapy was indicated. The patient is alive without recurrence.
UNASSIGNED: Despite its rarity, gastric liposarcoma should be respected for differential diagnosis in submucosal tumors. The main diagnostic method is histological, and surgery is the conventional treatment without yet having a consensus. Minimally invasive wedge resection might be a suitable treatment even if the location is close to the pylorus. Multicenter studies are required to obtain better results in the management of this pathology.

Hollow viscus perforation poses a significant diagnostic and therapeutic dilemma for the majority of clinicians. It is vitally important that in cases of gastrointestinal perforation, the tissue that was perforated is always evaluated, since a malignant tumor can cause this complication as a presentation form. Here, we present the case of a patient whose first manifestation of a malignant gastric tumor was its perforation and the presence of septic shock secondary to this. This case exemplifies the importance of innovative thinking in facilitating a comprehensive diagnostic and therapeutic strategy, leading to the timely identification and management of a malignant tumor by the oncology team; such interventions not only enhance patient outcomes but also mitigate morbidity and mortality rates.

OBJECTIVE: The objective of this study is to assess the clinical pathological attributes of Hepatoid Adenocarcinoma of the Stomach (HAS) and to delineate the differential diagnostic considerations about it.
METHODS: The investigation involved analyzing 31 HAS cases using histomorphological assessment, immunohistochemical profiling, and relevant gene detection methodologies.
RESULTS: Among the 31 HAS cases, 9 (29.0%) were of trabecular hepatoid adenocarcinoma of the stomach, 7 (22.6%) were of glandular hepatoid adenocarcinoma of the stomach, 4 (12.9%) were of nesting hepatoid adenocarcinoma of the stomach, 3 (9.7%) were of clear cell hepatoid adenocarcinoma of the stomach, and 8 (25.8%) were of diverse hepatoid adenocarcinoma of the stomach. Of these 31 cases, 24 were male, accounting for 77.4% of the cases. Serum alpha-fetoprotein (AFP) levels were notably elevated, with radioimmunoassay results reaching 1240 ng/ml; 28 out of 31 cases had AFP levels below 25 µg/l, accounting for 90.3%. Related genes: HER2 protein indicated positive expression on the cell membrane in 35.5% (11/31) of the cases; HER2 gene amplification detected by the FISH technique was 12.9% (4/31). Tumoral stromal lymphocytes exhibited a PD-1 positive expression rate of 58.1% (18/31). In gastric cancer tissues, the PD-L1 positive rate was 45.1% (14/31).
CONCLUSIONS: HAS represents a distinctive subtype of gastric cancer with a propensity for mimicking other forms of tumors, underscoring the significance of discerning its unique histopathological attributes for accurate differential diagnosis and tailored therapeutic interventions.

OBJECTIVE: Bleeding after endoscopic submucosal dissection (ESD) for gastric tumors in patients taking antithrombotic drugs, in particular direct oral anticoagulants (DOACs), remains unresolved; therefore, we evaluated the risk factors for post-ESD bleeding and drug differences in patients taking DOACs.
METHODS: We included 278 patients taking antithrombotic drugs who underwent gastric ESD between January 2017 and March 2022. Antithrombotic drugs were withdrawn following the 2017 guidelines (Appendix on anticoagulants including DOACs). To further clarify differences in antithrombotic agents\' effects, the peri-cancerous mucosa in the resected specimen was pathologically evaluated according to the Updated Sydney System. Multivariate analysis was performed to assess the risk of post-ESD bleeding.
RESULTS: The incidence of post-ESD bleeding in patients taking DOACs was 19.6% (10/51). Among patients taking antithrombotic drugs, DOACs were identified as a possible factor involved in post-ESD bleeding (odds ratio [OR] 4.92). Among patients taking DOACs, possible factors included resection length diameter ≥30 mm (OR 3.72), presence of neutrophil infiltration (OR 2.71), lesions occurring in the lower third of stomach (OR 2.34), and preoperative antiplatelet use (OR 2.22). Post-ESD bleeding by DOAC type was 25.0% of patients (4/16) receiving apixaban, in 20.0% (3/15) receiving edoxaban, in 21.4% (3/14) receiving rivaroxaban, and in none of those receiving dabigatran.
CONCLUSIONS: The administration of DOACs was shown to be a possible factor involved in post-ESD bleeding, and risk factors for patients taking DOACs included neutrophil infiltration. The pharmacological differences in the effects of DOACs contributing to bleeding in gastric ulcers suggest comparatively less bleeding with dabigatran after ESD.

This study showcases a novel AI-driven approach to accurately differentiate between stage one and stage two gastric carcinoma based on pathology slide analysis. Gastric carcinoma, a significant contributor to cancer-related mortality globally, necessitates precise staging for optimal treatment planning and patient management. Leveraging a comprehensive dataset of 3540 high-resolution pathology images sourced from Kaggle.com, comprising an equal distribution of stage one and stage two tumors, the developed AI model demonstrates remarkable performance in tumor staging. Through the application of state-of-the-art deep learning techniques on Google\'s Collaboration platform, the model achieves outstanding accuracy and precision rates of 100%, accompanied by notable sensitivity (97.09%), specificity (100%), and F1-score (98.31%). Additionally, the model exhibits an impressive area under the receiver operating characteristic curve (AUC) of 0.999, indicating superior discriminatory power and robustness. By providing clinicians with an efficient and reliable tool for gastric carcinoma staging, this AI-driven approach has the potential to significantly enhance diagnostic accuracy, inform treatment decisions, and ultimately improve patient outcomes in the management of gastric carcinoma. This research contributes to the ongoing advancement of cancer diagnosis and underscores the transformative potential of artificial intelligence in clinical practice.

Background: This study aimed to assess the completion rate and postoperative bleeding incidence of endoscopic submucosal dissection (ESD) for gastric tumors under continuous antithrombotic therapy. Methods: A prospective observational study was conducted including 88 patients with 100 gastric lesions who underwent gastric endoscopic submucosal dissection (ESD) and received continuous antithrombotic therapy. Additionally, retrospective data on gastric ESD in 479 patients with 534 lesions who did not receive antithrombotic therapy were collected for comparison. Results: The en bloc resection rates (100% in the continuous antithrombotic therapy group vs. 100% in the non-antithrombotic therapy group) and complete resection rates (97.0% vs. 96.3%, respectively) were high and comparable between the groups. No significant differences were found in the specimen size or procedure time. Perforation rates were low (0% vs. 2.3%, respectively) and were not significantly different between the groups. However, postoperative bleeding occurred significantly more frequently in the continuous antithrombotic therapy group (10.2% vs. 4.2%, respectively) than in the non-antithrombotic therapy group. The subgroup analysis revealed a higher incidence of postoperative bleeding in patients receiving thienopyridine derivatives. Conclusions: Continuous administration of antithrombotic agents, especially thienopyridines, increased the risk of postprocedural hemorrhage following gastric ESD. These findings support the need for careful consideration of pharamcological management before ESD, aligning with the current guidelines.

BACKGROUND: CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors, including gastric cancer (GC), and is associated with tumor progression and immune infiltration; however, the roles and mechanisms of CALD1 in epithelial-mesenchymal transition (EMT) in GC are unknown.
OBJECTIVE: To investigate the role and mechanism of CALD1 in GC progression, invasion, and migration.
METHODS: In this study, the relationship between CALD1 and GC, as well as the possible network regulatory mechanisms of CALD1, was investigated by bioinformatics and validated by experiments. CALD1-siRNA was synthesized and used to transfect GC cells. Cell activity was measured using the CCK-8 method, cell migration and invasive ability were measured using wound healing assay and Transwell assay, and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot. A GC cell xenograft model was established to verify the results of in vitro experiments.
RESULTS: Bioinformatics results showed that CALD1 was highly expressed in GC tissues, and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC. The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression, and a prognostic model was constructed and evaluated. The experimental results were consistent with the results of the bioinformatics analysis. The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1, with the strongest expression found in AGS and MKN45 cells. Cell activity was significantly reduced after CALD1-siRNA transfection of AGS and MKN45 cells. The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection, and the related mRNA and protein expression was altered. According to bioinformatics findings in GC samples, the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway, and was closely related to the PI3K-Akt signaling pathway. Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K, p-AKT, and p-mTOR, members of the PI3K-Akt pathway,while decreasing the expression of PTEN; PI3K-Akt inhibitor treatment decreased the expression of PI3K, p-AKT, and p-mTOR in cells overexpressing CALD1 (still higher than that in the normal group), but increased the expression of PTEN (still lower than that in the normal group). CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor. Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor. The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1, whereas the effect of overexpression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor. Animal experiments showed that tumour growth was slow after inhibition of CALD1, and the expression of some PI3K-Akt and EMT pathway proteins was altered.
CONCLUSIONS: Increased expression of CALD1 is a key factor in the progression, invasion, and metastasis of GC, which may be associated with regulating the PI3K-Akt pathway to promote EMT.

Gastric squamous cell carcinoma (SCC) is a rare and puzzling entity that challenges conventional paradigms of gastric malignancies, especially in young adults. This case report presents a 22-year-old male with invasive SCC of the stomach, emphasizing the rarity of such occurrences and their diagnostic challenges. The literature review underscores the scarcity of information on gastric SCC, necessitating a critical examination of its clinical implications, etiological factors, and optimal management. The patient\'s complex medical history, diagnostic journey, and treatment course are detailed, highlighting the importance of multidisciplinary collaboration and advanced diagnostic techniques. Immunohistochemistry is a crucial tool for precise tumor characterization, and the absence of established risk factors emphasizes the enigmatic nature of gastric SCC. This case report contributes to the understanding of gastric SCC, prompting further research into its unique features, etiology, and therapeutic strategies in the context of gastric cancer.

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) of the stomach is an uncommon mesenchymal neoplasm. We present a case of gastric submucosal tumor (SMT) where the final diagnosis was IMT.
METHODS: A 69-year-old man presented with a 24-mm SMT on the posterior wall of the middle third of the stomach that was detected by screening upper gastrointestinal endoscopy. Abdominal contrast-enhanced computed tomography showed that the tumor was well-enhanced. Although endoscopic ultrasonography-guided biopsy was performed, the histological diagnosis was not confirmed preoperatively. Since the tumor was clinically suspected to be a gastrointestinal stromal tumor, we performed gastric wedge resection by laparoscopic-endoscopic cooperative surgery. Pathologically, proliferative spindle cells with a positive reaction for smooth muscle actin, negativity for c-kit, desmin, s-100, CD34, STAT-6, β-catenin and anaplastic lymphoma kinase 1 were identified. Hence, the tumor was finally diagnosed as an IMT originating from the stomach.
CONCLUSIONS: When an SMT of the stomach is identified, the possibility of gastric IMT should be considered.