Real-time automated diagnosis of precancerous lesions and early esophageal squamous cell carcinoma using a deep learning model (with videos)

BACKGROUND AND AIMS

We developed a system for computer-assisted diagnosis (CAD) for real-time automated diagnosis of precancerous lesions and early esophageal squamous cell carcinomas (ESCCs) to assist the diagnosis of esophageal cancer.

METHODS

A total of 6473 narrow-band imaging (NBI) images, including precancerous lesions, early ESCCs, and noncancerous lesions, were used to train the CAD system. We validated the CAD system using both endoscopic images and video datasets. The receiver operating characteristic curve of the CAD system was generated based on image datasets. An artificial intelligence probability heat map was generated for each input of endoscopic images. The yellow color indicated high possibility of cancerous lesion, and the blue color indicated noncancerous lesions on the probability heat map. When the CAD system detected any precancerous lesion or early ESCCs, the lesion of interest was masked with color.

RESULTS

The image datasets contained 1480 malignant NBI images from 59 consecutive cancerous cases (sensitivity, 98.04%) and 5191 noncancerous NBI images from 2004 cases (specificity, 95.03%). The area under curve was 0.989. The video datasets of precancerous lesions or early ESCCs included 27 nonmagnifying videos (per-frame sensitivity 60.8%, per-lesion sensitivity, 100%) and 20 magnifying videos (per-frame sensitivity 96.1%, per-lesion sensitivity, 100%). Unaltered full-range normal esophagus videos included 33 videos (per-frame specificity 99.9%, per-case specificity, 90.9%).

CONCLUSIONS

A deep learning model demonstrated high sensitivity and specificity for both endoscopic images and video datasets. The real-time CAD system has a promising potential in the near future to assist endoscopists in diagnosing precancerous lesions and ESCCs.

Tissue engineering of tooth crown, root, and periodontium

Tissue engineering of teeth requires the coordinated formation of correctly shaped crowns, roots, and periodontal ligament. Previous studies have shown that the dental mesenchyme controls crown morphogenesis and epithelial histogenesis during tooth development in vivo, but little is known about the inductive potential of dissociated mesenchymal cells used in ex vivo cultures. A 2-step method is described in which, by using different types of reassociations between epithelial and mesenchymal tissues and/or cells from mouse embryos, reassociations were cultured in vitro before in vivo implantation. In vitro, the reassociated tissues developed and resulted in tooth-like structures that exhibited normal epithelial histogenesis and allowed the functional differentiation of odontoblasts and ameloblasts. After implantation, the reassociations formed roots and periodontal ligament, the latter connected to developing bone. The shape of the crown, initially suspected to depend on the integrity of the mesenchyme, could be modulated by adjusting the number of dissociated mesenchymal cells reassociated with the epithelial compartment. Based on these results, we propose a refined strategy for tooth tissue engineering that may help to eventually generate morphologically defined teeth.

Bone marrow cells can give rise to ameloblast-like cells

Post-eruptive loss of ameloblasts requires identification of alternative sources for these cells to realize tooth-tissue-engineering strategies. Recent reports showed that bone-marrow-derived cells can give rise to different types of epithelial cells, suggesting their potential to serve as a source for ameloblasts. To investigate this potential, we mixed c-Kit(+)-enriched bone marrow cells with embryonic dental epithelial cells and cultured them in re-association with dental mesenchyme. Non-dividing, polarized, and secretory ameloblast-like cells were achieved without cell fusion. Before basement membrane reconstitution, some bone marrow cells migrated to the mesenchyme, where they exhibited morphological, molecular, and functional characteristics of odontoblasts. These results show, for the first time, that bone-marrow-derived cells can be reprogrammed to give rise to ameloblast-like cells, offering novel possibilities for tooth-tissue engineering and the study of the simultaneous differentiation of one bone marrow cell subpopulation into cells of two different embryonic lineages.

An international study on the use of peroral endoscopic myotomy (POEM) in the management of esophageal diverticula: the first multicenter D-POEM experience

BACKGROUND

The aim of this study is to report a novel, multicenter experience with the diverticular peroral endoscopic myotomy (D-POEM) technique in the management of esophageal diverticula.

METHODS

This is a multicenter, international, retrospective study involving three centers. D-POEM was performed using the principles of submucosal endoscopy.

RESULTS

A total of 11 patients with an esophageal diverticulum (Zenker's 7, mid-esophagus 1, epiphrenic 3) were included. The mean size of the esophageal diverticula was 34.5 mm. The overall technical success rate of D-POEM was 90.9 %, with a mean procedure time of 63.2 minutes. There were no adverse events. Clinical success was achieved in 100 % (10 /10), with a decrease in mean dysphagia score from 2.7 to 0.1 (P < 0.001) during a median follow-up of 145 days (interquartile range 126 - 273).

CONCLUSION

Endoscopic management of esophageal diverticula using the novel technique of D-POEM appears promising. This first case series on D-POEM suggests that the procedure is feasible, safe, and effective in the management of esophageal diverticula. D-POEM offers the distinct advantage of ensuring a complete septotomy. Larger studies are needed to confirm these intriguing results.

An international study on the use of peroral endoscopic myotomy in the management of Zenker's diverticulum

BACKGROUND AND AIMS

The novel use of peroral endoscopic myotomy (POEM) in the treatment of Zenker's diverticulum (ZD) was recently described in case reports. The aim of this study is to report a multicenter experience with the POEM technique in the management of ZD.

METHODS

This is a multicenter international retrospective study involving 10 centers. The Zenker's POEM technique was performed using principles of submucosal endoscopy.

RESULTS

Seventy-five patients (73.3 ± 1.2 years, 33 women) were included with a mean Charleson comorbidity index of 4 ± .2. The mean size of ZD was 31.3 ± 1.6 mm (range, 10-89). The overall technical success rate was 97.3% (73/75). There were 2 technical failures because of the inability to locate the septum and failed tunnel creation. Adverse events occurred in 6.7% (5/75): 1 bleed (mild) conservatively managed and 4 perforations (1 severe, 3 moderate). The mean procedure time was 52.4 ± 2.9 minutes, and mean length of hospital stay was 1.8 ± .2 days. Clinical success was achieved in 92% (69/75) with a decrease in mean dysphagia score from 1.96 to .25 (P < .0001). The median length of follow-up was 291.5 days (interquartile range, 103.5-436). At the 12-month follow-up, 1 patient reported symptom recurrence.

CONCLUSIONS

Endoscopic management of ZD using the POEM technique is novel and feasible with promising efficacy and safety results. Long-term follow-up is needed to ensure durability of response. In addition, comparative studies with other treatment modalities are warranted.

Vascularization of engineered teeth

The implantation of cultured dental cell-cell re-associations allows for the reproduction of fully formed teeth, crown morphogenesis, epithelial histogenesis, mineralized dentin and enamel deposition, and root-periodontium development. Since vascularization is critical for organogenesis and tissue engineering, this work aimed to study: (a) blood vessel formation during tooth development, (b) the fate of blood vessels in cultured teeth and re-associations, and (c) vascularization after in vivo implantation. Ex vivo, blood vessels developed in the dental mesenchyme from the cap to bell stages and in the enamel organ, shortly before ameloblast differentiation. In cultured teeth and re-associations, blood-vessel-like structures remained in the peridental mesenchyme, but never developed into dental tissues. After implantation, both teeth and re-associations became revascularized, although later in the case of the re-associations. In implanted re-associations, newly formed blood vessels originated from the host, allowing for their survival, and affording conditions organ growth, mineralization, and enamel secretion.

Dental Epithelial Histomorphogenesis in vitro

Recent developments in tooth-tissue engineering require that we understand the regulatory processes to be preserved to achieve histomorphogenesis and cell differentiation, especially for enamel tissue engineering. Using mouse first lower molars, our objectives were: (1) to determine whether the cap-stage dental mesenchyme can control dental epithelial histogenesis, (2) to test the role of the primary enamel knot (PEK) in specifying the potentialities of the dental mesenchyme, and (3) to evaluate the importance of positional information in epithelial cells. After tissue dissociation, the dental epithelium was further dissociated into individual cells, re-associated with dental mesenchyme, and cultured. Epithelial cells showed a high plasticity: Despite a complete loss of positional information, they rapidly underwent typical dental epithelial histogenesis. This was stimulated by the mesenchyme. Experiments performed at E13 demonstrated that the initial potentialities of the mesenchyme are not specified by the PEK. Positional information of dental epithelial cells does not require the memorization of their history.

RAB10 overexpression promotes tumor growth and indicates poor prognosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC), one of the most common and lethal cancers worldwide, has a high recurrence rate with current treatment modalities. Identifying biomarkers for early diagnosis and discovering new sufficient molecular targets for the development of targeted therapies are urgently needed. RAB10, a member of the RAS family, has been shown to be highly expressed in HCC. However, the function of RAB10 in HCC is less studied. Here we report that RAB10 acts as an oncogene in HCC. The shRNA-mediated knockdown of RAB10 significantly reduced the proliferation of HCC cells and colony formation, induced cell cycle arrest at G0/G1 phase and increased apoptosis in vitro. In addition, RAB10 knockdown suppressed HCC growth in nude mice. Moreover, RAB10 silencing decreased the phosphorylation of InsR, Met/HGFR, Ron/MST1R, Ret, c-Kit/SCFR, EphA3, EphB4, Tyro3/Dtk, Axl, Tie2/TEK, VEGFR2/KDR, Akt/PKB/Rac, S6 Ribosomal Protein and c-Abl, while the phosphorylation of HSP27, p38 MAPK, Chk2 and TAK1 increased significantly. These results suggest that RAB10 regulates cell survival and proliferation through multiple oncogenic, cell stress and apoptosis pathways. More importantly, high RAB10 expression levels in HCC cells correlated with a poor prognosis in HCC patients. Therefore, our findings revealed an oncogenic role for RAB10 in the pathogenesis of HCC and that RAB10 is a potential molecular target or a biomarker for HCC.

Dental epithelial histo-morphogenesis in the mouse: positional information versus cell history

Reciprocal epithelial-mesenchymal interactions control odontogenesis and the cap stage tooth germ mesenchyme specifies crown morphogenesis. The aim of this work was to determine whether this mesenchyme could also control epithelial histogenesis. Dental mesenchyme and enamel organ were dissociated from mouse first lower molars at E14. At this early cap stage, the enamel organ consists of four cell types forming the inner dental epithelium (IDE), primary enamel knot (PEK), outer dental epithelium (ODE) and the stellate reticulum (SR). Pelleted trypsin-dissociated single dental epithelial cells, which had lost all positional information, were reassociated to either dental mesenchyme or dissociated mesenchymal cells and cultured in vitro. Although with different timings, teeth developed in both types of experiments showing a characteristic dental epithelial histogenesis, cusp formation, and the differentiation of functional odontoblasts and ameloblasts. The rapid progression of the initial steps of histogenesis suggested that the cell history was not memorized. The dental mesenchyme, as well as dissociated mesenchymal cells, induced the formation of a PEK indicating that no specific organisation in the mesenchyme is required for this step. However, the proportion of well-formed multicusped teeth was much higher when intact mesenchyme was used instead of dissociated mesenchymal cells. The mesenchymal cell dissociation had consequences for the functionality of the newly-formed PEK.

A new expression plasmid in Bifidobacterium longum as a delivery system of endostatin for cancer gene therapy

To utilize Bifidobacterium longum (B. longum) as a safe and stable delivery system for endostatin in cancer gene therapy, we constructed pBV22210 vector combining a chloramphenicol-resistance gene (Cm(r)) from pBCSK(+) plasmid, a cryptic plasmid pMB1 from B. longum strain with pBV222. Endostatin was cloned directly downstream of an N terminal His6-tag sequence in the pBV22210, so that the endostatin protein expressed in B. longum could be purified with Ni-binding resin. The results indicated that the plasmid electroporated into B. longum was maintained stably in the absence of selective antibiotics and did not significantly affect biological characteristics of B. longum. In addition, the plasmid in B. longum showed a strong inhibitory effect on the growth of mouse solid liver tumor in vivo. These results suggested that this new plasmid may be a stable vector in B. longum for transporting anti-cancer genes in cancer gene therapy.

Native, oxidized lipoprotein(a) and lipoprotein(a) immune complex in patients with active and inactive rheumatoid arthritis: plasma concentrations and relationship to inflammation

BACKGROUND

Several studies suggest that lipoprotein (a) [Lp(a)] act as acute phase reactant and be associated with early atherosclerosis in rheumatoid arthritis (RA). Oxidized Lp(a) [ox-Lp(a)] and Lp(a) immune complex (IC) concentrations both increased in patients with coronary heart disease. We investigated Lp(a), ox-Lp(a) and Lp(a)-IC concentrations in RA patients and to explore the relationships with inflammatory disease activity markers.

METHODS

Plasma Lp(a), ox-Lp(a) and Lp(a)-IC concentrations, and inflammatory markers were analyzed in 54 patients with RA, including 23 active and 21 inactive RA, and 60 control subjects.

RESULTS

Lp(a) and ox-Lp(a) concentrations in active RA were higher than those in both inactive RA and control; Lp(a)-IC concentrations in active RA were also higher than inactive RA, while no difference was found in Lp(a), ox-Lp(a) and Lp(a)-IC concentrations between inactive RA and control. Lp(a) concentrations were found positively correlated with ox-Lp(a) and Lp(a)-IC concentrations, respectively; ox-Lp(a) concentrations were also related with Lp(a)-IC. Lp(a), ox-Lp(a) and Lp(a)-IC were all found positively related with C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), respectively.

CONCLUSIONS

Native, oxidized Lp(a) and Lp(a)-IC concentrations increased in active RA patients. Inflammation may induce the changes of Lp(a), resulting in increased ox-Lp(a) and Lp(a)-IC, and may play an important role in atherosclerosis.

Bifidobacterium longum as a delivery system of TRAIL and endostatin cooperates with chemotherapeutic drugs to inhibit hypoxic tumor growth

In our previous study, we have shown that vector pBV22210 containing a chloramphenicol resistance and a cryptic plasmid pMB1 from Bifidobacterium longum strain could stably replicate and did not significantly affect the biological characteristics of B. longum. In this study, B. longum was transfected by electroporation with pBV22210 encoding the extracellular domain of TRAIL (B. longum-pBV22210-TRAIL) and its carbohydrate fermentation and growth curve were determined, and its location and inhibitory effect on tumor xenografts in mice were also examined. The results further proved that gene transfection did not change the main biochemical characteristics of B. longum. The results also showed that B. longum-pBV22210-TRAIL resulted in selective location in tumors and exhibited a definite antitumor effect on S180 osteosarcoma. In addition, when a low dosage of Adriamycin (5 mg kg(-1)) or B. longum-pBV22210-endostatin was combined, the antitumor effect was significantly enhanced. The successful inhibition of S180 tumor growth suggested a stable vector in B. longum for transporting anticancer genes combined with low-dose chemotherapeutic drugs or other target genes is a promising approach in cancer gene therapy.

Identifying a confused cell identity for esophageal squamous cell carcinoma

The cell identity of malignant cells and how they acquire it are fundamental for our understanding of cancer. Here, we report that esophageal squamous cell carcinoma (ESCC) cells display molecular features equally similar but distinct to all three types of normal esophageal epithelial cells, which we term as confused cell identity (CCI). CCI is an independent prognostic marker associated with poor prognosis in ESCC. Further, we identify tropomyosin 4 (TPM4) as a critical CCI gene that promotes the aggressiveness of ESCC in vitro and in vivo. And TPM4 creates CCI through activating the Jak/STAT-SOX2 pathway. Thus, our study suggests an unrecognized feature of ESCC cells, which might be of value for clinic prognosis and potential interference.

Analysis of the DPYD gene implicated in 5-fluorouracil catabolism in Chinese cancer patients

BACKGROUND AND OBJECTIVE

5-fluorouracil (5-FU) is still a widely used anticancer drug. More than 85% of the 5-FU administered is catabolized by dihydropyrimidine dehydrogenase (DPD) in the liver. However, mutations in the DPD gene have been found to be associated with low DPD activity causing severe complications. The purpose of this study was to determine the mutation frequency of four exons in Chinese cancer patients and the relationship between genotype and DPD activity.

METHODS

Samples from 142 cancer patients were investigated in this study. The DPD activity was determined by reversed-phase HPLC. Exons 2, 13, 14 and 18 were amplified by polymerase chain reaction (PCR), sequenced and analysed from both sense and antisense directions. Nonparametric one-sample Kolmogorov-Smirnov test was used for distribution analysis; two independent samples t-test and one-way anova was performed for two groups and three groups analyses, respectively.

RESULTS AND DISCUSSION

Plasma-DPD activities in the 142 cancer patients followed a Gaussian distribution. The mean plasma-DPD activity in women was lower than that in men (P = 0.006). Four mutations, 85T>C(DPYD*9A), 1627A>G(DPYD*5), 1896T>C and 2194G>A(DPYD*6), were found in the 142 cancer patients. The following mutations reported by others were not detected: 61C>T, 62G>A, 74A>G, 1601G>A(DPYD*4), 1679T>G(DPYD*13), 1714C>G, 1897delC(DPYD*3) and IVS 14 + 1G>A. No significant correlation was found between three mutations [85T>C(DPYD*9A), 1627A>G (DPYD*5) and 1896T>C], and DPD activity was found.

CONCLUSION

No clear correlation between the mutations studied and DPD activity could be established in this study. However, larger-scale prospective studies are needed to better assess the reported genotype-phenotype correlations.

Martrilin-3 (MATN3) Overexpression in Gastric Adenocarcinoma and its Prognostic Significance

BACKGROUND The aim of this study was to investigate the expression level of martrilin-3 (MATN3) in patients with gastric adenocarcinoma (GAC) and to investigate the prognostic significance of MATN3. MATERIAL AND METHODS Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) data were used to predict the expression and prognostic value of MATN3 mRNA in GAC patients. Seventy-six GAC patients had GAC tissue samples and paired adjacent normal tissue samples collected retrospectively to examine the MATN3 protein expression level by immunohistochemical staining. Furthermore, Kaplan-Meier univariate and Cox multivariate analyses were used to verify the correlation between MATN3 expression and clinicopathological parameters of GAC patients and the prognostic significance of MATN3. RESULTS The GEO and TCGA data predicted that MATN3 mRNA levels were significantly higher in GAC tissue compared to normal tissue (all p<0.05). Further survival analyses showed that GAC patients with high mRNA expression of MATN3 had significantly lower disease-free survival (DFS) and overall survival (OS) time than those with low mRNA expression of MATN3 (all p<0.05). Subsequent immunohistochemical staining results confirmed that the MATN3 protein levels in GAC tissues were highly expressed (p=0.000) compared to normal tissues. In addition, GAC patients with high protein expression of MATN3 had remarkably decreased OS compared to patients with low protein expression of MATN3 (p=0.000). Univariate and multivariate survival analyses revealed that MATN3 high expression could be used as an independent predictor of poor prognosis in GAC patients (all p=0.000). CONCLUSIONS This study confirmed that MATN3 protein was highly expressed in GAC patients, and MATN3 overexpression could be used as an independent predictor of poor prognosis in GAC patients.

Melatonin and tryptophan circadian profiles in patients with advanced non-small cell lung cancer

INTRODUCTION

Accumulating studies indicate that melatonin is a natural oncostatic agent capable of mediating the influence of the psychoneuroendocrine system on cancer growth. Although there is increasing evidence to show that the pineal gland may play a role in human non-small cell lung cancer (NSCLC), there is uncertainty about circadian profiles of melatonin, its precursor tryptophan, and its major metabolite, 6-sulfatoxymelatonin (6-OH-MLT) in NSCLC patients before and after treatment with standard chemotherapy (cisplatin plus vinorelbine). The aim of this study was to investigate the concentration changes of melatonin, tryptophan, and 6-OH-MLT in NSCLC patients treated with standard chemotherapy.

METHODS

We examined the circadian melatonin, tryptophan, and 6-OH-MLT rhythms in 30 patients suffering from advanced-stage NSCLC and compared them with those of 63 healthy volunteers free from neoplastic disease. Blood samples were collected at 12 noon and 12 midnight. Urine samples were collected at 7 AM: and 4 PM: . The levels of melatonin in serum and of 6-OH-MLT in urine were measured by high-performance liquid chromatography. The concentration of amino acids including tryptophan in serum was measured by amino acid analyzer.

RESULTS

Melatonin, tryptophan, and 6-OH-MLT concentrations were significantly lower in cancer patients, in comparison with healthy subjects. A significant inverse correlation between melatonin and tryptophan was observed. Additionally, after three cycles of standard chemotherapy, there was a tendency of melatonin, tryptophan, and 6-OH-MLT concentrations to progressively decrease in NSCLC patients.

CONCLUSION

The results of the present study indicate that the presence of NSCLC influences the metabolism of melatonin, and chemotherapy in NSCLC patients may progressively decrease the production of melatonin.

Hypoxia-inducible factor 1α in breast cancer prognosis

BACKGROUND

Recent studies have assessed the relationship between hypoxia-inducible factor 1α (HIF-1α) expression and prognosis in breast cancer patients with inconsistent conclusions. To comprehensively and quantitatively summarize the evidence on the survival of patients with breast cancer, a meta-analysis was performed.

METHODS

Systematic literature searching was applied to the databases of PubMed, Embase and Web of science until April 1, 2013. Pooled HR with 95% CI was used to evaluate the association between HIF-1α expression and survival in breast cancer patients.

RESULTS

Fourteen papers including 2933 patients were subjected to the final analysis. Of these, 7 provided data on overall survival (OS), 8 on disease-free survival (DFS), 3 on distant metastasis-free survival (DMFS) and 3 on relapse-free survival (RFS). We observed that high expression of HIF-1α in breast cancer patients was an indicator of poor prognosis on OS (HR = 1.46, 95% CI: 1.12-1.92, P = 0.006), DFS (HR = 1.91, 95% CI: 1.43-2.57, P<0.001), DMFS (HR=2.17 95% CI: 1.16-4.05, P=0.015) and RFS (HR=1.33 95% CI: 1.09-1.61, P=0.005). Significant heterogeneity was observed in the analyses of OS and DFS. Subgroup analyses by the cut-off value and antibody for IHC were conducted.

CONCLUSION

High expression of HIF-1α indicated a poor prognosis for patients with breast cancer.

Pilot study of urgent endoscopic intervention without fluoroscopy on patients with severe acute biliary pancreatitis in the intensive care unit

OBJECTIVE

The effect of early endoscopic intervention (EI; within 72 hours) remains a controversial subject. This prospective study was aimed to evaluate the efficacy of early EI without fluoroscopy on severe acute biliary pancreatitis (SABP) in the intensive care unit (ICU).

METHODS

Fifty-three patients with SABP + ampullary obstruction in the ICU were divided randomly into 2 groups: conservative treatment in the ICU (CTI arm) and CTI + EI without the aid of fluoroscopy (CTI + EI arm). Decreased Acute Physiology and Chronic Health Evaluation II score was the major parameter to assess treatment efficacy.

RESULTS

Endoscopic treatments including sphincterotomy + stone removal (17 cases) and nasobiliary drainage (4 cases) were successfully performed in all 21 enrolled patients without the aid of fluoroscopy in the ICU. Compared with CTI, CTI + EI significantly resulted in decreased (3.86 +/- 2.08 vs 6.57 +/- 1.54) Acute Physiology and Chronic Health Evaluation II score at day 10, P < 0.05. No deaths were observed in the CTI + EI, whereas the CTI arm had 2 mortalities.

CONCLUSIONS

Urgent EI without fluoroscopy is possible to be performed by endoscopists with the experience from high volume of procedures and is beneficial for the patients with SABP in the ICU or community hospital.

Artificial intelligence-based assessments of colonoscopic withdrawal technique: a new method for measuring and enhancing the quality of fold examination

BACKGROUND

This study aimed to develop an artificial intelligence (AI)-based system for measuring fold examination quality (FEQ) of colonoscopic withdrawal technique. We also examined the relationship between the system's evaluation of FEQ and FEQ scores from experts, and adenoma detection rate (ADR) and withdrawal time of colonoscopists, and evaluated the system's ability to improve FEQ during colonoscopy.

METHODS

First, we developed an AI-based system for measuring FEQ. Next, 103 consecutive colonoscopies performed by 11 colonoscopists were collected for evaluation. Three experts graded FEQ of each colonoscopy, after which the recorded colonoscopies were evaluated by the system. We further assessed the system by correlating its evaluation of FEQ against expert scoring, historical ADR, and withdrawal time of each colonoscopist. We also conducted a prospective observational study to evaluate the system's performance in enhancing fold examination.

RESULTS

The system's evaluations of FEQ of each endoscopist were significantly correlated with experts' scores (r = 0.871, P < 0.001), historical ADR (r = 0.852, P = 0.001), and withdrawal time (r = 0.727, P = 0.01). For colonoscopies performed by colonoscopists with previously low ADRs (< 25 %), AI assistance significantly improved the FEQ, evaluated by both the AI system (0.29 [interquartile range (IQR) 0.27-0.30] vs. 0.23 [0.17-0.26]) and experts (14.00 [14.00-15.00] vs. 11.67 [10.00-13.33]) (both P < 0.001).

CONCLUSION

The system's evaluation of FEQ was strongly correlated with FEQ scores from experts, historical ADR, and withdrawal time of each colonoscopist. The system has the potential to enhance FEQ.

Chronic inflammation and long-lasting changes in the gastric mucosa after Helicobacter pylori infection involved in gastric cancer

OBJECTIVE

Helicobacter pylori (H. pylori) infects approximately half of the world's population, as one of the most common chronic infections. H. pylori infection has been widely recognized as a major risk factor for gastric cancer (GC).

METHODS

Eradication treatment is considered to abolish the inflammatory response and prevent progression to GC. However, only 1-3% of H. pylori-infected patients develop GC, whereas GC can occur even after eradicating H. pylori. In addition, the incidence of GC following H. pylori infection is significantly higher compared to the gross incidence induced by all causes, although eradicating H. pylori reduces the risk of developing GC.

RESULTS

Therefore, it is reasonable to hypothesize that H. pylori infection results in changes that persist even after its eradication. Several of these changes may not be reversible within a short time, including the status of inflammation, the dysfunction of immunity and apoptosis, mitochondrial changes, aging and gastric dysbacteriosis.

CONCLUSION

The present review article aimed to discuss these potential long-lasting changes induced by H. pylori infection that may follow the eradication of H. pylori and contribute to the development of GC.

Immunological Perspective: Helicobacter pylori Infection and Gastritis

Helicobacter pylori is a spiral-shaped gram-negative bacterium. Its infection is mainly transmitted via oral-oral and fecal-oral routes usually during early childhood. It can achieve persistent colonization by manipulating the host immune responses, which also causes mucosal damage and inflammation. H. pylori gastritis is an infectious disease and results in chronic gastritis of different severity in near all patients with infection. It may develop from acute/chronic inflammation, chronic atrophic gastritis, intestinal metaplasia, dysplasia, and intraepithelial neoplasia, eventually to gastric cancer. This review attempts to cover recent studies which provide important insights into how H. pylori causes chronic inflammation and what the characteristic is, which will immunologically explain H. pylori gastritis.

Peroral endoscopic myotomy for the treatment of esophageal diverticulum: an experience in China

BACKGROUND

With the development of minimally invasive endoscopic approaches for the esophagus in recent years, peroral endoscopic myotomy (POEM) in the treatment of esophageal diverticulum has been described recently in some reports due to its successful outcomes. The aim of this study is to report our experience with the use of diverticular POEM (D-POEM) technique in the management of esophageal diverticulum.

METHODS

This retrospective study included consecutive patients with symptomatic esophageal diverticulum who visited our endoscopy center between April 2014 and January 2019. D-POEM was performed based on the principles of submucosal endoscopy. A new symptomatic scoring system was introduced to evaluate the severity of diverticular symptoms.

RESULTS

A total of 10 patients with esophageal diverticulum (Zenker's 2, mid-esophagus 5, and epiphrenic 3) were included. The overall technical success rate of D-POEM was 100%, with a mean procedure time of 38.9 ± 20.5 (range 16-70) min. No serious complications occurred. Clinical improvement was achieved in 90% (9/10) of patients. The symptomatic score was significantly decreased from 2.5 (IQR 2.00-3.25) to 1.0 (IQR 0-1.25) (P = 0.007) during a median follow-up period of 11.0 (IQR 10.25-17.25) months.

CONCLUSION

These findings suggested complete septotomy by D-POEM. Our preliminary data and experience put forwarded D-POEM as a safe and effective technique for esophageal diverticulum.

Gastric epithelial histology and precancerous conditions

The most common histological type of gastric cancer (GC) is gastric adenocarcinoma arising from the gastric epithelium. Less common variants include mesenchymal, lymphoproliferative and neuroendocrine neoplasms. The Lauren scheme classifies GC into intestinal type, diffuse type and mixed type. The WHO classification includes papillary, tubular, mucinous, poorly cohesive and mixed GC. Chronic atrophic gastritis (CAG) and intestinal metaplasia are recommended as common precancerous conditions. No definite precancerous condition of diffuse/poorly/undifferentiated type is recommended. Chronic superficial inflammation and hyperplasia of foveolar cells may be the focus. Presently, the management of early GC and precancerous conditions mainly relies on endoscopy including diagnosis, treatment and surveillance. Management of precancerous conditions promotes the early detection and treatment of early GC, and even prevent the occurrence of GC. In the review, precancerous conditions including CAG, metaplasia, foveolar hyperplasia and gastric hyperplastic polyps derived from the gastric epithelium have been concluded, based on the overview of gastric epithelial histological organization and its renewal.

Overexpression of Coiled-Coil Domain-Containing Protein 34 (CCDC34) and its Correlation with Angiogenesis in Esophageal Squamous Cell Carcinoma

BACKGROUND The coiled-coil domain-containing proteins have been shown to have a series of functions in biological synthesis. Recent studies have found that CCDC34 is highly expressed in bladder cancer, but the underlying molecular mechanisms still remain unclear. Therefore, we performed the present study to assess the expression of the coiled-coil domain-containing protein 34 (CCDC34) in esophageal squamous cell carcinoma (ESCC) patients. We also explored the relationships between CCDC34 expression and clinicopathologic characteristics, tumor angiogenesis, and prognosis. MATERIAL AND METHODS We detected the expressions of CCDC34, VEGF, and MVD by immunohistochemical technique in 100 cases of ESCC and 80 cases of corresponding paracarcinomatous normal tissues. The relationship between CCDC34 expression and clinicopathologic characteristics, tumor angiogenesis, and prognosis were also explored. RESULTS The expression of CCDC34 protein was obviously increased in ESCC tissues, which was significantly correlated with sex (p=0.038), TNM stage (p=0.003), and lymphatic metastasis (p=0.024). In addition, we found that the expression of CCDC34 was an independent prognostic factor for ESCC patients. The overexpression of CCDC34 protein in ESCC was associated with tumor progression, angiogenesis, and poor survival. CONCLUSIONS Our results demonstrate that CCDC34 is overexpressed in ESCC and can be used as an independent parameter for indicating the poor prognosis of ESCC patients, suggesting that CCDC34 might be a new potential therapeutic target for ESCC patients in the future.

Recent advances in early esophageal cancer: diagnosis and treatment based on endoscopy

Esophageal cancer (EC) often cannot be discovered in time because of its asymptomatic or symptom-atypical characteristics in early stage. The risk and probability of lymph node metastasis and distant metastasis increase correspondingly as the cancer aggressively invades deeper layers. Treatment regimens may be shifted to surgery and chemoradiotherapy (CRT) from endoscopic eradication therapy (EET) with poor quality of life and prognosis. It is imperative to identify dysplasia and EC early and enable early curative endoscopic treatments. Newer methods have been attempted in the clinical setting to achieve early detection at a more microscopic and precise level. Newer imaging techniques and artificial intelligence (AI) technology have been involved in targeted biopsies and will gradually unveil the visualization of pathology in the future. Early detection and diagnosis are the prerequisite to choose personal and precise treatment regimens. EET has also been undergoing development and improvement to benefit more patients as the first option or the firstly chosen alternative therapy, when compared with esophagectomy. More clinical studies are needed to provide more possibilities for EET.