Choice of LECS Procedure for Benign and Malignant Gastric Tumors

Exploring the correlation between gut microbiota and benign gastric tumors: A Mendelian randomization study

Recent scientific research has verified a link between malignant tumors in the stomach and the gut microbiota. This research employed Mendelian randomization (MR) techniques to explore the association between gut microbiota and benign gastric malignancies. The data were derived from genome wide association studies-aggregated data consisting of 211 gut microbes and benign gastric lesions and analyzed by MR. Five statistical tools, including inverse variance weighting, weighted median, MR-Egger, simple mode, and weighted mode, were employed in the statistical analysis. The utilization of the leave-one-out approach served as an effective means of detecting data outliers. Furthermore, implementing Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) and MR-Egger intercepts was employed to mitigate the impact of horizontal pleiotropy. The Cochran Q scores for inverse variance weighting and MR-Egger were utilized to determine the extent of heterogeneity. The findings indicate that the family Porphyromonadaceae (odds ratio [OR] = 2.185, 95% confidence interval [CI]: 1.239-3.855, P = .007), class Bacilli (OR = 1.556, 95%CI: 1.091 - 2.220, P = .015), family Lactobacillaceae (OR = 1.437, 95%CI: 1.049 - 1.969, P = .024), family Oxalobacteraceae (OR = 1.290, 95%CI: 1.035 - 1.608, P = .023) are positively associated with the occurrence of benign gastric tumors. Conversely, the family Pasteurellaceae (OR = 0.752, 95%CI: 0.566 - 0.999, P = .049) and family Peptococcaceae (OR = 0.622, 95%CI: 0.425 - 0.908, P = .014) exhibit a protective effect and significantly decrease the likelihood of benign gastric tumors. The findings of this study suggest that the probability of developing benign gastric tumors is positively associated with the presence of the family Porphyromonadaceae, class Bacilli, family Lactobacillaceae and family Oxalobacteraceae, In contrast, the presence of the family Pasteurellaceae and family Peptococcaceae is negatively associated with this risk. Therefore, regulating gut microbiota may be a potential strategy to reduce the incidence of benign gastric tumors.

Non-exposed endoscopic wall-inversion surgery with one-step nucleic acid amplification for early gastrointestinal tumors: Personal experience and literature review

BACKGROUND

Laparoscopic and endoscopic cooperative surgery is a safe, organ-sparing surgery that achieves full-thickness resection with adequate margins. Recent studies have demonstrated the safety and efficacy of these procedures. However, these techniques are limited by the exposure of the tumor and mucosa to the peritoneal cavity, which could lead to viable cancer cell seeding and the spillage of gastric juice or enteric liquids into the peritoneal cavity. Non-exposed endoscopic wall-inversion surgery (NEWS) is highly accurate in determining the resection margins to prevent intraperitoneal contamination because the tumor is inverted into the visceral lumen instead of the peritoneal cavity. Accurate intraoperative assessment of the nodal status could allow stratification of the extent of resection. One-step nucleic acid amplification (OSNA) can provide a rapid method of evaluating nodal tissue, whilst near-infrared laparoscopy together with indocyanine green can identify relevant nodal tissue intraoperatively.

AIM

To determine the safety and feasibility of NEWS in early gastric and colon cancers and of adding rapid intraoperative lymph node (LN) assessment with OSNA.

METHODS

The patient-based experiential portion of our investigations was conducted at the General and Oncological Surgery Unit of the St. Giuseppe Moscati Hospital (Avellino, Italy). Patients with early-stage gastric or colon cancer (diagnosed via endoscopy, endoscopic ultrasound, and computed tomography) were included. All lesions were treated by NEWS procedure with intraoperative OSNA assay between January 2022 and October 2022. LNs were examined intraoperatively with OSNA and postoperatively with conventional histology. We analyzed patient demographics, lesion features, histopathological diagnoses, R0 resection (negative margins) status, adverse events, and follow-up results. Data were collected prospectively and analyzed retrospectively.

RESULTS

A total of 10 patients (5 males and 5 females) with an average age of 70.4 ± 4.5 years (range: 62-78 years) were enrolled in this study. Five patients were diagnosed with gastric cancer. The remaining 5 patients were diagnosed with early-stage colon cancer. The mean tumor diameter was 23.8 ± 11.6 mm (range: 15-36 mm). The NEWS procedure was successful in all cases. The mean procedure time was 111.5 ± 10.7 min (range: 80-145 min). The OSNA assay revealed no LN metastases in any patients. Histologically complete resection (R0) was achieved in 9 patients (90.0%). There was no recurrence during the follow-up period.

CONCLUSION

NEWS combined with sentinel LN biopsy and OSNA assay is an effective and safe technique for the removal of selected early gastric and colon cancers in which it is not possible to adopt conventional endoscopic resection techniques. This procedure allows clinicians to acquire additional information on the LN status intraoperatively.

Endoscopic advances in the management of gastric cancer and premalignant gastric conditions

Gastric cancer is the fifth most common cancer and in 2018, it was the third most common cause of cancer-related deaths worldwide. Endoscopic advances continue to be made for the diagnosis and management of both early gastric cancer and premalignant gastric conditions. In this review, we discuss the epidemiology and risk factors of gastric cancer and emphasize the differences in early vs late-stage gastric cancer outcomes. We then discuss endoscopic advances in the diagnosis of early gastric cancer and premalignant gastric lesions. This includes the implementation of different imaging modalities such as narrow-band imaging, chromoendoscopy, confocal laser endomicroscopy, and other experimental techniques. We also discuss the use of endoscopic ultrasound in the diagnosis and staging of early gastric cancer. We then discuss the endoscopic advances made in the treatment of these conditions, including endoscopic mucosal resection, endoscopic submucosal dissection, and hybrid techniques such as laparoscopic endoscopic cooperative surgery. Finally, we comment on the current suggested recommendations for surveillance of both gastric cancer and its premalignant conditions.

Robot-assisted laparoscopic partial gastrectomy combined with endoscopy for gastrointestinal stromal tumors with intraluminal growth: a report of two cases

In cases of gastrointestinal stromal tumor (GIST) with intraluminal growth, determining the minimal resection line is difficult; however, the combined use of endoscopy can overcome this limitation. We performed robot-assisted partial gastrectomy with endoscopy for two cases of internally developed GISTs located on the posterior wall near the esophagogastric junction (EGJ). We confirmed the tumor location and determined minimal surgical margins using endoscopy. The double bipolar method (DBM), which is performed with Maryland bipolar forceps in the right hand and fenestrated bipolar forceps in the left hand, was used to reduce residual gastric damage and prevent tumor damage. The characteristics of robot-assisted surgery made it easier to precisely perform anastomosis of the upper part of the stomach, as compared with laparoscopic surgery, thus minimizing gastric deformity. Both patients were discharged without postoperative complications. In conclusion, robot-assisted partial gastrectomy using the DBM may represent a viable treatment option for gastric submucosal tumors close to the EGJ.

The First Systematic Gastroscopy Training Program for Surgeons in Korea

BACKGROUND

Endoscopic evaluation of the stomach is essential for preoperative planning and post-surgical surveillance for various diseases of the stomach, including malignancy. The gastroscopy education program for surgeons is currently in its infancy and is not systematically organized in Korea. This study aimed to introduce the first systematic gastroscopy education program for surgeons in Korea.

METHODS

The gastroscopy education program entitled "Gastroscopy School for Surgeons (GSS)" comprised of theoretical education, dry lab hands-on training, and clinical practice. All participants were beginners without any gastroscopy experience. Clinical practice started after the completion of the theoretical and dry lab training. The gastroscopy practices utilized simple luminal observation, biopsy, localization using clips or dye injection, and limited therapeutic gastroscopy. The educational performances and surveys from 33 participants were analyzed.

RESULTS

The participants consisted of surgical residents, general surgeons, gastrointestinal-specialized surgeons, and physicians. Participants performed a total of 2,272 gastroscopies, 2,008 of which were post-gastrectomy cases. Currently, of the 33 participants, 7 (21.2%) of the participants performed gastroscopy regularly, and 7 (21.2%) occasionally. According to the self-reported survey, one participant assessed their current gastroscopic technique to be at the expert level, and 25 (75.8%) at a proficient level. All participants considered gastroscopy education for surgeons to be necessary, and 28 (84.8%) stated that systematic education is not currently provided in Korea.

CONCLUSION

We introduced the first systematic gastroscopy education program for surgeons in Korea, namely the GSS, which is practical and meets clinical needs. More training centers are needed to expand gastroscopy training among Korean surgeons.

Laparoscopic and endoscopic cooperative surgery for full-thickness resection and sentinel node dissection for early gastric cancer

The endoscopic submucosal dissection (ESD) technique has become the gold standard for submucosal tumors that have negligible risk of lymph node metastasis (LNM), due to its minimal invasiveness and ability to improve quality of life. However, this technique is limited in stage T1 cancers that have a low risk of LNM. Endoscopic full thickness resection can be achieved with laparoscopic endoscopic cooperative surgery (LECS), which combines laparoscopic gastric wall resection and ESD. In LECS, the surgical margins from the tumor are clearly achieved while performing organ-preserving surgery. To overcome the limitation of classical LECS, namely the opening of the gastric wall during the procedure, which increases the risk of peritoneal tumor seeding, non-exposed endoscopic wall-inversion surgery was developed. With this full-thickness resection technique, contact between the intra-abdominal space and the intragastric space was eliminated.

Identification and Validation of an m6A Modification of JAK-STAT Signaling Pathway–Related Prognostic Prediction Model in Gastric Cancer

Background: Gastric cancer (GC) is one of the malignant tumors worldwide. Janus (JAK)–signal transduction and activator of transcription (STAT) signaling pathway is involved in cellular biological process and immune function. However, the association between them is still not systematically described. Therefore, in this study, we aimed to identify key genes involved in JAK-STAT signaling pathway and GC, as well as the potential mechanism.

Methods: The Cancer Genome Atlas (TCGA) database was the source of RNA-sequencing data of GC patients. Gene Expression Omnibus (GEO) database was used as the validation set. The predictive value of the JAK-STAT signaling pathway-related prognostic prediction model was examined using least absolute shrinkage and selection operator (LASSO); survival, univariate, and multivariate Cox regression analyses; and receiver operating characteristic curve (ROC) analyses to examine the predictive value of the model. Quantitative real-time polymerase chain reaction (qRT-PCR) and chi-square test were used to verify the expression of genes in the model and assess the association between the genes and clinicopathological parameters of GC patients, respectively. Then, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set enrichment analysis, version 3.0 (GSEA), sequence-based RNA adenosine methylation site predictor (SRAMP) online websites, and RNA immunoprecipitation (RIP) experiments were used to predict the model-related potential pathways, m6A modifications, and the association between model genes and m6A.

Results: A four-gene prognostic model (GHR, PIM1, IFNA8, and IFNB1) was constructed, namely, riskScore. The Kaplan–Meier curves suggested that patients with high riskScore expression had a poorer prognosis than those with low riskScore expression (p = 0.006). Multivariate Cox regression analyses showed that the model could be an independent predictor (p < 0.001; HR = 3.342, 95%, CI = 1.834–6.088). The 5-year area under time-dependent ROC curve (AUC) reached 0.655. The training test set verified these results. Further analyses unveiled an enrichment of cancer-related pathways, m6A modifications, and the direct interaction between m6A and the four genes.

Conclusion: This four-gene prognostic model could be applied to predict the prognosis of GC patients and might be a promising therapeutic target in GC.

Early gastric cancer: A challenge in Western countries

Early gastric cancer (EGC) is an invasive carcinoma involving only the stomach mucosa or submucosa, independently of lymph node status. EGC represents over 50% of cases in Japan and in South Korea, whereas it accounts only for approximately 20% of all newly diagnosed gastric cancers in Western countries. The main classification systems of EGC are the Vienna histopathologic classification and the Paris endoscopic classification of polypoid and non-polypoid lesions. A careful endoscopic assessment is fundamental to establish the best treatment of EGC. Generally, EGCs are curable if the lesion is completely removed by endoscopic resection or surgery. Some types of EGC can be resected endoscopically; for others the most appropriate treatment is surgical resection and D2 lymphadenectomy, especially in Western countries. The favorable oncological prognosis, the extended lymphadenectomy and the reconstruction of the intestinal continuity that excludes the duodenum make the prophylactic cholecystectomy mandatory to avoid the onset of biliary complications.

Clinicopathological features and management strategy for superficial nonampullary duodenal tumors: a multi-center retrospective study

Purpose

We investigated the clinicopathological features and management for superficial nonampullary duodenal tumors (SNADTs). The safety and feasibility of laparoscopic management, especially laparoscopic endoscopic cooperative surgery (LECS), were evaluated.

Methods

A total of 59 patients with SNADTs who underwent operations from January 2009 to December 2018 at all 8 institutions of the Catholic Medical Center were identified in our comprehensive multi-institutional database. Clinicopathological and surgical data on the 4 anatomical regions of the duodenum were collected and compared. Characteristics of conventional laparoscopic procedure (laparoscopy-only) and LECS procedures were also compared.

Results

There were significantly more asymptomatic patients with tumors in the first and second vs. third and fourth duodenal regions. Gastrointestinal stromal tumors (GISTs), carcinoids, and ectopic pancreatic tumors were identified in 32, 12, and 5 cases, respectively. Forty-two patients (71.2%) underwent laparoscopy. Of patients undergoing laparoscopy, the LECS group exhibited significantly more endophytic features and smaller tumor sizes (P < 0.001 and P < 0.001, respectively). Although no significant difference in the wedge resection or postoperative complication rate was seen between the 2 groups (P = 0.096 and P = 0.227, respectively), the wedge resection rate was higher, and the complication rate lower, in the LECS group than the conventional laparoscopic surgery group.

Conclusion

Most of the SNADTs located in proximal duodenum were detected incidentally. GISTs were the most common diagnoses of SNADTs in all locations. In treating these tumors, laparoscopic resection is safe and feasible. Especially, LECS may be ideal for treating small endophytic tumors, minimizing over-resection and postoperative complications.