Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and treatment.Understanding the evolution and current state of research in this field is vital.AIM To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic evolution.METHODS This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and CiteSpace.The analysis focused on the distribution of publications,contributions by institutions and countries,and trends in keywords.The methods included data synthesis,network analysis,and visualization of international collaboration networks.RESULTS This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration.It highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute.The last five years,substantial advancements have been made,representing nearly 45%of the examined literature.Publication rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research efforts.This study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication outlet.This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks.CONCLUSION This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis.This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy,ultimately enhancing worldwide patient care.

Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions:Clinical significance

Transoral endoscopic resections in treating upper gastrointestinal submucosal lesions have the advantages of maintaining the integrity of the gastrointestinal lumen,avoiding perforation and reducing gastrointestinal fistulae.They are becoming more widely used in clinical practice,but,they may also present a variety of complications.Gas-related complications are one of the most common,which can be left untreated if the symptoms are mild,but in severe cases,they can lead to rapid changes in the respiratory and circulatory systems in a short period,which can be life-threatening.Therefore,it is important to predict the occurrence of gas-related complications early and take preventive measures actively.Based on the authors'results in the prepublication of the article“Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions,”and in conjunction with our evaluation and additions to the relevant content,radiographs may help screen patients at high risk for gas-related complications.Controlling blood glucose levels,shortening the duration of surgery,and choosing the most appropriate surgical resection may positively impact the prognosis of patients at high risk for gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions.

Nomogram to predict gas-related complications during transoral endoscopic resection of upper gastrointestinal submucosal lesions

BACKGROUND Gas-related complications present a potential risk during transoral endoscopic resection of upper gastrointestinal submucosal lesions.Therefore,the identification of risk factors associated with these complications is essential.AIM To develop a nomogram to predict risk of gas-related complications following transoral endoscopic resection of the upper gastrointestinal submucosal lesions.METHODS We collected patient data from the First Affiliated Hospital of the Army Medical University.Patients were randomly allocated to training and validation cohorts.Risk factors for gas-related complications were identified in the training cohort using univariate and multivariate analyses.We then constructed a nomogram and evaluated its predictive performance based on the area under the curve,decision curve analysis,and Hosmer-Lemeshow tests.RESULTS Gas-related complications developed in 39 of 353 patients who underwent transoral endoscopy at our institution.Diabetes,lesion origin,surgical resection method,and surgical duration were incorporated into the final nomogram.The predictive capability of the nomogram was excellent,with area under the curve values of 0.841 and 0.906 for the training and validation cohorts,respectively.CONCLUSION The ability of our four-variable nomogram to efficiently predict gas-related complications during transoral endoscopic resection enhanced postoperative assessments and surgical outcomes.

From the mathematical model to the patient: The scientific and human aspects of artificial intelligence in gastrointestinal surgery

Recent medical literature shows that the application of artificial intelligence(AI)models in gastrointestinal pathology is an exponentially growing field,with pro-mising models that show very high performances.Regarding inflammatory bowel disease(IBD),recent reviews demonstrate promising diagnostic and prognostic AI models.However,studies are generally at high risk of bias(especially in AI models that are image-based).The creation of specific AI models that improve diagnostic performance and allow the establishment of a general prognostic fo-recast in IBD is of great interest,as it may allow the stratification of patients into subgroups and,in turn,allow the creation of different diagnostic and therapeutic protocols for these patients.Regarding surgical models,predictive models of post-operative complications have shown great potential in large-scale studies.In this work,the authors present the development of a predictive algorithm for early post-surgical complications in Crohn's disease based on a Random Forest model with exceptional predictive ability for complications within the cohort.The pre-sent work,based on logical and reasoned,clinical,and applicable aspects,lays a solid foundation for future prospective work to further develop post-surgical prognostic tools for IBD.The next step is to develop in a prospective and mul-ticenter way,a collaborative path to optimize this line of research and make it applicable to our patients.

Risk factors for complications associated with upper gastrointestinal foreign bodies

AIM: To investigate predictive risk factors associated with complications in the endoscopic removal of foreign bodies from the upper gastrointestinal tract.METHODS: We retrospectively reviewed the medical records of 194 patients with a diagnosis of foreign body impaction in the upper gastrointestinal tract,confirmed by endoscopy,at two university hospital in South Korea.Patient demographic data,including age,gender,intention to ingestion,symptoms at admission,and comorbidities,were collected.Clinical features of the foreign bodies,such as type,size,sharpness of edges,number,and location,were analyzed.Endoscopic data those were analyzed included duration of foreign body impaction,duration of endoscopic performance,endoscopic device,days of hospitalization,complication rate,30-d mortality rate,and the number of operationsrelated to foreign body removal.RESULTS: The types of upper gastrointestinal foreign bodies included fish bones,drugs,shells,meat,metal,and animal bones.The locations of impacted foreign bodies were the upper esophagus(57.2%),mid esophagus(28.4%),stomach(10.8%),and lower esophagus(3.6%).The median size of the foreign bodies was 26.2 ± 16.7 mm.Among 194 patients,endoscopic removal was achieved in 189,and complications developed in 51 patients(26.9%).Significant complications associated with foreign body impaction and removal included deep lacerations with minor bleeding(n = 31,16%),ulcer(n = 11,5.7%),perforation(n = 3,1.5%),and abscess(n = 1,0.5%).Four patients underwent operations because of incomplete endoscopic foreign body extraction.In multivariate analyses,risk factors for endoscopic complications and failure were sharpness(HR = 2.48,95%CI: 1.07-5.72; P = 0.034) and a greater than 12-h duration of impaction(HR = 2.42,95%CI: 1.12-5.25,P = 0.025).CONCLUSION: In cases of longer than 12 h since foreign body ingestion or sharp-pointed objects,rapid endoscopic intervention should be provided in patients with ingested foreign bodies.

Gastrointestinal complications of diabetes mellitus

Diabetes mellitus affects virtually every organ system in the body and the degree of organ involvement depends on the duration and severity of the disease,and other co-morbidities.Gastrointestinal(GI) involvement can present with esophageal dysmotility,gastro-esophageal reflux disease(GERD),gastroparesis,enteropathy,non alcoholic fatty liver disease(NAFLD) and glycogenic hepatopathy.Severity of GERD is inversely related to glycemic control and management is with prokinetics and proton pump inhibitors.Diabetic gastroparesis manifests as early satiety,bloating,vomiting,abdominal pain and erratic glycemic control.Gastric emptying scintigraphy is considered the gold standard test for diagnosis.Management includes dietary modifications,maintaining euglycemia,prokinetics,endoscopic and surgical treatments.Diabetic enteropathy is also common and management involves glycemic control and symptomatic measures.NAFLD is considered a hepatic manifestation of metabolic syndrome and treatment ismainly lifestyle measures,with diabetes and dyslipidemia management when coexistent.Glycogenic hepatopathy is a manifestation of poorly controlled type 1 diabetes and is managed by prompt insulin treatment.Though GI complications of diabetes are relatively common,awareness about its manifestations and treatment options are low among physicians.Optimal management of GI complications is important for appropriate metabolic control of diabetes and improvement in quality of life of the patient.This review is an update on the GI complications of diabetes,their pathophysiology,diagnostic evaluation and management.

Sedation-related complications in gastrointestinal endoscopy

Sedation practices for gastrointestinal endoscopic(GIE) procedures vary widely in different countries depending on health system regulations and local circumstances. The goal of procedural sedation is the safe and effective control of pain and anxiety, as well as to provide an appropriate degree of memory loss or decreased awareness. Sedation-related complications in gastrointestinal endoscopy, once occurred, can lead to significant morbidity and occasional mortality in patients. The risk factors of these complications include the type, dose and mode of administration of sedative agents, as well as the patient's age and underlying medical diseases. Complications attributed to moderate and deep sedation levels are more often associated with cardiovascular and respiratory systems. However, sedation-related complications during GIE procedures are commonly transient and of a mild degree. The risk for these complications while providing any level of sedation is greatest when caring for patients already medically compromised. Significant unwanted complications can generally be prevented by careful pre-procedure assessment and preparation, appropriate monitoring and support, as well as post-procedure management. Additionally, physicians must be prepared to manage these complications. This article will review sedation-related complications duringmoderate and deep sedation for GIE procedures and also address their appropriate management.

Ultraslim endoscopy with flexible spectral imaging color enhancement for upper gastrointestinal neoplasms

AIM:To conduct a preliminary study on the effect of flexible spectral imaging color enhancement (FICE) used in combination with ultraslim endoscopy by focusing on the enhanced contrast between tumor and non-tumor lesions. METHODS: We examined 50 lesions of 40 patients with epithelial tumors of the upper gastrointestinal tract before endoscopic submucosal dissection using ultraslim endoscopy with conventional natural color imag ing and with FICE imaging. We retrospectively invest igated the effect of the use of FICE on endoscopic diagn osis in comparison with normal light. RESULTS: Visibility of the epithelial tumors of the upper gastrointestinal tract with FICE was superior to normal light in 54% of the observations and comparable to normal light in 46% of the observations. There was no lesion for which visibility with FICE was inferior to that with normal light. FICE visualized 69.6% of hyperemic lesions and 58.8% of discolored lesions better than conventional endoscopy with natural color imaging. FICE sign if icantly improved the visibility of lesions with hyp ere mia or discoloration compared with normocolored lesions. CONCLUSION: This study suggests that the use of FICE would improve the ability of ultraslim endoscopy to detect epithelial tumors of the upper gastrointestinal tract.

Role of endoscopy in management of gastrointestinal complications of portal hypertension

The management of patients with gastrointestinal complications of portal hypertension is often complex and challenging. The endoscopy plays an important role in the management of these patients. The role of endoscopy is both diagnostic and interventional and in the last years the techniques have undergone a rapid expansion with the advent of different and novel endoscopic modalities, with consequent improvement of investigation and treatment of these patients. The choice of best therapeutic strategy depends on many factors: baseline disease, patient's clinical performance and the timing when it is done if in emergency or a prophylactic approaches. In this review we evaluate the endoscopic management of patients with the gastrointestinal complications of portal hypertension.

Mixed neuroendocrine–nonneuroendocrine neoplasms of the gastrointestinal system:An update

Mixed neuroendocrine-nonneuroendocrine neoplasms(Mi NENs)of the digestive tract are a rare heterogeneous group of tumors that present many challenges in terms of diagnosis and treatment.Over the years,the diagnostic criteria,classification,and clinical behavior of these tumors have been the subjects of ongoing debate,and the various changes in their nomenclature have strengthened the challenges associated with Mi NENs.This review is performed to provide an understanding of the key factors involved in the evolution of the designation of these tumors as Mi NEN,highlight the current diagnostic criteria,summarize the latest data on pathogenesis and provide information on available treatments.Moreover,this work seeks to increase the awareness about these rare neoplasms by presenting the clinicopathological features and prognostic factors that play important roles in their behavior and discussing their different regions of origin in the gastrointestinal system(GIS).Currently,the Mi NEN category also includes tumors in the GIS with a nonneuroendocrine component and epithelial tumors other than adenocarcinoma,depending on the organ of origin.Diagnosis is based on the presence of both morphological components in more than 30%of the tumor.However,this value needs to be reconfirmed with further studies and may be a limiting factor in the diagnosis of Mi NEN by biopsy.Furthermore,available clinicopathological data suggest that the inclusion of amphicrine tumors in the definition of Mi NEN is not supportive and warrants further investigation.The diagnosis of these tumors is not solely based on immunohistochemical findings.They are not hybrid tumors and both components can act independently;thus,careful grading of each component separately is required.In addition to parameters such as the metastatic state of the tumor at the time of diagnosis and the feasibility of surgical resection,the aggressive potential of both components has paramount importance in the choice of treatment.Regardless of the organ of origin within the GIS,almost Mi NENs are tumors with poor prognosis and are frequently encountered in the elderly and men.They are most frequently reported in the colorectum,where data from molecular studies indicate a monoclonal origin;however,further studies are required to provide additional support for this origin.

Gastrointestinal bleeding as initial presentation of extramedullary plasma cell neoplasms: A case report and review of the literature

BACKGROUND Plasma-cell neoplasms rarely involve the gastrointestinal tract and manifest as gastrointestinal bleeding. Plasmablastic myeloma is an aggressive plasma cell neoplasm associated with poor outcomes. A small number of cases with gastrointestinal involvement is reported in the literature and therefore high index of suspicion is essential for avoiding delays in diagnosis and treatment.CASE SUMMARY Our aim is to present our experience of a 70-year-old patient with a secondary presentation of plasmablastic myeloma manifesting as unstable upper gastrointestinal bleeding and to review the literature with the view to consolidate and discuss information about diagnosis and management of this rare entity. In addition to our case, a literature search(Pub Med database) of case reports of extramedullary plasma cell neoplasms manifesting as upper gastrointestinal bleeding was performed. Twenty-seven cases of extramedullary plasmacytoma(EMP) involving the stomach and small bowel presenting with upper gastrointestinal bleeding were retrieved. The majority of patients were males(67%). The average age on diagnosis was 62.7 years. The most common site of presentation was the stomach(41%), followed by the duodenum(15%). The most common presenting complaint was melena(44%). In the majority of cases, the EMPs were a secondary manifestation(63%) at the background of multiple myeloma(26%), plasmablastic myeloma(7%) or high-grade plasma cell myeloma(4%). Oesophagogastroscopy was the main diagnostic modality and chemotherapy the preferred treatment option for secondary EMPs.CONCLUSION Despite their rare presentation, upper gastrointestinal EMPs should be considered in the differential diagnosis of patients with gastrointestinal bleeding especially in the presence of systemic haematological malignancy.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.

Heating infusion for gastrointestinal complications in patients with enteral nutrition: A meta-analysis

Objective: To systematically evaluate the effects of heating infusion on gastrointestinal complications of patients with enteral nutrition. Methods: The domestic and foreign databases including Cochrane Library, PubMed, EMBASE, Web of Science, Chinese biomedical literature database (CBM), Wan Fang database (Wan Fang), China National Knowledge Infrastructure (CNKI) and VIP Database for Chinese Technical Periodicals(VIP) were retrieved. The retrieval contents were randomized controlled trials on improving gastrointestinal complications of patients with enteral nutrition by heating infusion of nutrient solution. Data were collected by two reviewers according to the data extraction tables. Results: A total of 17 randomized controlled trials with 1683 subjects were chosen. The results of meta analysis showed that the rate of abdominal pain, abdominal distension and nausea in patients with enteral nutrition could be reduced by warm infusion of nutrient solution, but the effect of the infusion on vomiting, constipation, stomach retention and diarrhea was not superior. Conclusion: Heating infusion of nutrient solution can reduce the incidence of abdominal pain, abdominal distension and nausea in patients with enteral nutrition.

A new breakthrough:ESD using a newly developed grasping type scissor forceps for early gastrointestinal tract neoplasms

Endoscopic submucosal dissection(ESD) has allowed the achievement of histologically curative en bloc resection of gastrointestinal neoplasms regardless of size,permitting the resection of previously non-resectable tumors.The ESD technique for treatment of early gastric cancer has spread rapidly in Japan and a few other Asian countries due to its excellent eradication rate compared to endoscopic mucosal resection.Although numerous electrosurgical knives have been developed for ESD,technical difficulties and high complication rates(bleeding and perforation) have limited their use worldwide.We developed the grasping type scissor forceps(GSF) to resolve such ESD-related problems.Our animal and preliminary clinical studies showed that ESD using GSF is a safe(no intraoperative complication) and technically efficient(curative en bloc resection rate 92%) method for dissection of early gastrointestinal tumors.The use of GSF is a promising option for performing ESD on early stage GI tract tumors both safely and effectively.

Does testosterone prevent early postoperative complications after gastrointestinal surgery?

AIM:To investigate the role of sex hormones in the early postoperative complications of gastrointestinal diseases. METHODS:A total of 65 patients who underwent operations for gastric and colorectal diseases(mainly malignant diseases)were included in the study. Peripheral venous blood samples were collected at different times for analysis of estradiol,testosterone and progesterone.The only study endpoint was analysis of postoperative complications. RESULTS:Patients of both sexes were uniform but postoperative complication rate was significantly higher in female patients(P=0.027).There was no significant association of estradiol and progesterone with postoperative complications.Testosterone levels in complicated patients were significantly lower than in uncomplicated patients(P<0.05).Area under the receiver operating characteristic curve showed that a lower value of testosterone was a predictor for higher complication rate(P<0.05),and a lower value oftestosterone at later times after surgery was a better predictor of complications. CONCLUSION:Patients with low testosterone level were prone to higher postoperative complications,which was evident in both sexes.However,further studies are necessary to support this result.

Conventional radiological strategy of common gastrointestinal neoplasms

This article summarizes the clinical characteristics and imaging features of common gastrointestinal(GI) neoplasms in terms of conventional radiological imaging methods. Barium studies are readily available for displaying primary malignancies and are minimallyor not at all invasive. A neoplasm may be manifested as various imaging findings, including mucosal disruption, soft mass, ulcer, submucosal invasion and lumen stenosis on barium studies. Benign tumors typically appear as smoothly marginated intramural masses. Malignant neoplasms most often appear as irregular infiltrative lesions on barium examination. Tumor extension to adjacent GI segments may be indistinct on barium images. Cross-sectional images such as computed tomography and magnetic resonance imaging may provide more accurate details of the adjacent organ invasion, omental or peritoneal spread.

Nomogram for predicting early complications after distal gastrectomy

BACKGROUND Reducing or preventing postoperative morbidity in patients with gastric cancer(GC)is particularly important in perioperative treatment plans.AIM To identify risk factors for early postoperative complications of GC post-distal gastrectomy and to establish a nomogram prediction model.METHODS This retrospective study included 131 patients with GC who underwent distal gastrectomy at the Second Hospital of Shandong University between January 2019 and February 2023.The factors influencing the development of complications after distal gastrectomy in these patients were evaluated using univariate and multivariate logistic regression analysis.Based on the results obtained,a predictive nomogram was established.The nomogram was validated using internal and external(n=45)datasets.Its sensitivity and specificity were established by receiver operating characteristic curve analysis.Decision curve(DCA)analysis was used to determine its clinical benefit and ten-fold overfitting was used to establish its accuracy and stability.RESULTS Multivariate logistic regression analysis showed that hypertension,diabetes,history of abdominal surgery,and perioperative blood transfusion were independent predictors of postoperative complications of distal gastrectomy.The modeling and validation sets showed that the area under the curve was 0.843[95%confidence interval(CI):0.746-0.940]and 0.877(95%CI:0.719-1.000),the sensitivity was 0.762 and 0.778,respectively,and the specificity was 0.809 and 0.944,respectively,indicating that the model had good sensitivity and specificity.The C-indexes of the modeling and validation datasets were 0.843(95%CI:0.746-0.940)and 0.877(95%CI:0.719-1.000),respectively.The calibration curve(Hosmer Lemeshow test:χ^(2)=7.33)showed that the model had good consistency.The results of the DCA analysis indicated that this model offered good clinical benefits.The accuracy of 10-fold cross-validation was 0.878,indicating that the model had good accuracy and stability.CONCLUSION The nomogram prediction model based on independent risk factors related to postoperative complications of distal gastrectomy can facilitate perioperative intervention for high-risk populations and reduce the incidence of postoperative complications.

Unusual complication in patient with Gardner's syndrome: Coexistence of triple gastrointestinal perforation and lower gastrointestinal bleeding: A case report and review of literature

Gardner's syndrome(GS) is a rare syndrome with autosomal dominant inheritance, which is characterized by multiple intestinal polyps, dental anomalies, desmoid tumors, and soft tissue tumors. All gastrointestinal symptoms seen in GS are associated with the underlying familial adenomatosis polyposis and abdominal desmoid tumors, with the most common symptoms being anemia, lower gastrointestinal bleeding, abdominal pain, diarrhea, obstruction, and mucous defecation. To our best knowledge, no case of GS that has presented with gastrointestinal perforation and bleeding has ever been reported in the English language medical literature. A 37-year-old male who had been diagnosed with GS five years earlier was referred to our clinic for lower gastrointestinal bleeding. Despite the absence of a bleeding focus on conventional angiography, the patient was operated on with laparotomy, due to the persistence of both signs and symptoms of mild peritonitis. On the laparotomy, the patient was noted to have areas of perforation in the duodenum, splenic flexura, and midrectum. The third and fourth part of the duodenum, the proximal 15 cm segment of the jejunum, a 10 cm segment of the terminal ileum, the whole colon, and the upper and middle rectum were resected, and duodenojejunal side-to-side anastomosis and terminal ileostomy were performed. The histopathological analysis of the large mass measuring 30 cm × 20 cm was reported as a desmoid tumor. The pathological examination of the tumor foci detected in the colonic specimen revealed poorly differentiated adenosquamous carcinoma.

Bioenergetic alteration in gastrointestinal cancers:The good,the bad and the ugly

Cancer cells exhibit metabolic reprogramming and bioenergetic alteration,utilizing glucose fermentation for energy production,known as the Warburg effect.However,there are a lack of comprehensive reviews summarizing the metabolic reprogramming,bioenergetic alteration,and their oncogenetic links in gastrointestinal(GI)cancers.Furthermore,the efficacy and treatment potential of emerging anticancer drugs targeting these alterations in GI cancers require further evaluation.This review highlights the interplay between aerobic glycolysis,the tricarboxylic acid(TCA)cycle,and oxidative phosphorylation(OXPHOS)in cancer cells,as well as hypotheses on the molecular mechanisms that trigger this alteration.The role of hypoxia-inducible transcription factors,tumor suppressors,and the oncogenetic link between hypoxia-related enzymes,bioenergetic changes,and GI cancer are also discussed.This review emphasizes the potential of targeting bioenergetic regulators for anti-cancer therapy,particularly for GI cancers.Emphasizing the potential of targeting bioenergetic regulators for GI cancer therapy,the review categorizes these regulators into aerobic glycolysis/lactate biosynthesis/transportation and TCA cycle/coupled OXPHOS.We also detail various anti-cancer drugs and strategies that have produced pre-clinical and/or clinical evidence in treating GI cancers,as well as the challenges posed by these drugs.Here we highlight that understanding dysregulated cancer cell bioenergetics is critical for effective treatments,although the diverse metabolic patterns present challenges for targeted therapies.Further research is needed to comprehend the specific mechanisms of inhibiting bioenergetic enzymes,address side effects,and leverage high-throughput multi-omics and spatial omics to gain insights into cancer cell heterogeneity for targeted bioenergetic therapies.

Three cases of jejunal tumors detected by standard upper gastrointestinal endoscopy:A case series

BACKGROUND In patients with obscure gastrointestinal bleeding,re-examination with standard upper endoscopes by experienced physicians will identify culprit lesions in a substantial proportion of patients.A common practice is to insert an adult-sized forward-viewing endoscope into the second part of the duodenum.When the endoscope tip enters after the papilla,which is a marker for the descending part of the duodenum,it is difficult to endoscopically judge how far the duodenum has been traversed beyond the second part.CASE SUMMARY We experienced three cases of proximal jejunal masses that were diagnosed by standard upper gastrointestinal endoscopy and confirmed with surgery.The patients visited the hospital with a history of melena;during the initial upper gastrointestinal endoscopy and colonoscopy,the bleeding site was not confirmed.Upper gastrointestinal bleeding was suspected;thus,according to guidelines,upper endoscopy was performed again.A hemorrhagic mass was discovered in the small intestine.The lesion of the first patient was thought to be located in the duodenum when considering the general insertion depth of a typical upper gastrointestinal endoscope;however,during surgery,it was confirmed that it was in the jejunum.After the first case,lesions in the second and third patients were detected at the jejunum by inserting the standard upper endoscope as deep as possible.CONCLUSION The deep insertion of standard endoscopes is useful for the diagnosis of obscure gastrointestinal bleeding.