Early Screening Of Gastric Cancer Research Articles

Development and Application of Magnetically Controlled Capsule Endoscopy in Detecting Gastric Lesions

In the past 20 years, several magnetically controlled capsule endoscopes (MCCE) have been developed for the evaluation of gastric lesions, including NaviCam (ANKON), MiroCam-Navi (Intromedic), Endocapsule MGCE (Olympus and Siemens), SMCE (JIFU), and FAMCE (Jinshan). Although limited to observing esophageal and duodenal lesions and lacking the ability of biopsy, MCCE has the advantages of comfort, safety, no anesthesia, no risk of cross-infection, and high acceptability. Several high-quality RCTs showed that the diagnostic accuracy of MCCE is comparable to the traditional gastroscopy. Due to the nonnecessity of anesthesia, MCCE may be more suitable for the elderly with obvious comorbidities as well as children. With more evidences accumulated and more innovative technologies developed, MCCE is expected to be an important tool for screening of early gastric cancer or the diagnosis of gastric diseases.

Screening of early gastric cancer using Pre-Activation Squeeze-and-Excitation ResNet

To propose a quick and accurate method for screening early gastric cancer based on Pre-Activation Squeeze- and-Exception ResNet (PASE-ResNet) gastroscopy images in limited labeled data sets. We developed an algorithm based on Pre-Activation Squeeze- and-Exception ResNet for early gastric cancer screening. To focus on the taskrelated image region and enhance the feature expression ability of model, we combined the Squeeze-and-Exception (SE) module with the residual module in PreAct-ResNet to adjust the weight of the feature channel. The strategy of local screening + global sliding window was adopted to improve the performance of early cancer screening. After data expansion, 18 400 set subgraphs were obtained, and the gastroscopy images were examined using the PASE-ResNet model by sliding window. The results of experiments showed that the proposed algorithm had good performance for screening early gastric cancer with an accuracy of 98.03%, a sensitivity of 98.96% and a specificity of 96.52%. The PASE-ResNet can achieve a high accuracy for screening early gastric cancer.

Design of Low-Cost Endoscope Based on Novel Wire-Driven Rotary Valve and Water-Jet Mechanism

Abstract To improve the prevalence of screening for gastric cancer in low-income areas, a low-cost endoscope based on a novel wire-driven rotary valve and water-jet mechanism is proposed. The primary component of this endoscope is a rotary valve whose core is driven by a stepper motor through a flexible wire, which controls the direction of the water jet. This enables it to reach any point in the workspace by controlling the valve core angle and water-jet intensity. The envelope surface of the endoscope tip trajectory is likely a hemisphere. The horizontal diameter of the working space projection is approximately 350 mm, which is sufficient to observe most parts of the greater curvature of the stomach. The image-acquisition performance of the designed endoscope was satisfactory in a phantom experiment. The introduction of the novel rotary valve greatly simplifies the structure and reduces the cost of the proposed endoscope. With low cost and high portability, this endoscope provides a good alternative for early gastric cancer screening in low- and middle-income areas.

STROBE-clinical characteristics and prognosis factors of gastric cancer in young patients aged ≤30 years.

We aimed to determine the clinical characteristics and prognosis factors of young patients with gastric cancer (GC).A total of 101 young patients with GC referred to Zhengzhou University People's Hospital, Henan province, China between January 1st, 2003 and June 1st, 2015 were retrospectively reviewed. The medical records included ages, genders, marital status, family history of tumors, comorbidity, Helicobacter pylori (H.pylori) infection, fibrinogen, prealbumin, alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), tumor location, tumor size, TNM stage, differentiation of the tumor, WHO type, treatment method and prognostic factors effect were further assessed.The mean age of GC patients in our group was 26.0 years. The incidence was slightly higher in females (female: male = 1.1:1). Some patients had the family history of tumor and H.pylori infection (2.0%, 6.9%). The tumor sizes were mainly under 5 cm (52.4%) and the most locations were in the antrum (43.5%) and body (42.5%). A large number of patients were diagnosed as adenocarcinomas (66.3%) and the main histological of GC was poor differentiated (72.3%). Moreover, a high proportion of patients were diagnosed at the stages III-IV (61.4%), and most patients received surgery combined chemotherapy (63.4%), however, the survival outcome was poor. In univariate Cox analysis, tumor sizes, TNM stage were significantly associated with overall survival (OS) and the multivariate Cox analysis demonstrated that TNM stage was significantly associated with OS.GC in young patients has its unique biological and clinical features. A large majority of young patients were diagnosed at their advanced stages with poor prognostic. TNM stage was an independent prognostic factor for young patients with GC, early GC screening in young people should be actively promoted.

Development of a New Combination Platform for the Early Screening of Gastric Cancer Using Serum Biomarkers

Objective: The combination of pepsinogens (PG I/II) and gastrin-17 (G17) has been used to screen GC in many countries, without satisfactory levels of sensitivity or specificity. The aim of this study was to find a better marker and a new modality in screening early GC. Methods: We measured the serum levels of PG I/II, G17, and prealbumin (PA) from the serum of 481 healthy individuals, 407 benign gastric diseases (BGD), and 416 GC patients using a latex particle-enhanced turbidimetric immunoassay and Sandwich ELISA. Logistic regression analysis was used to obtain the sensitivity and specificity of the combined detection model. Results: When PA was combined with the other biomarkers, the sensitivity and specificity were significantly improved in the ROC curve. The combination of PA+G17+PGI+PGR was the best diagnostic combination for both early and late GC. The AUC, sensitivity, and specificity of the combination for discriminating between early GC and healthy individuals were 0.796, 72.1% and 74.2% respectively. For distinguishing patients with early GC from BGD, the AUC, sensitivity and specificity of the combination were 0.696, 66.7% and 65.4%, respectively. The combination of PA+G17+PGI+PGR improved both the sensitivity and the specificity of GC diagnosis compared with those of the traditional combination of G17+PGI+ PGII +PGR. Conclusion: PA is a valuable indicator for GC and interacts synergistically with PG and G17 in screening for early GC. The new combination platform PA+G17+PGI+PGR may be a potential way for the early screening of GC.

Automatic Detection of Gastric Wall Structure Based on Oral Contrast-Enhanced Ultrasound and Its Application on Tumor Screening.

Gastric cancer is the second most lethal type of malignant tumor in the world. Early diagnosis of gastric cancer can reduce the transformation to advanced cancer and improve the early treatment rate. As a cheap, real-time, non-invasive examination method, oral contrast-enhanced ultrasonography (OCUS) is a more acceptable way to diagnose gastric cancer than interventional diagnostic methods such as gastroscopy. In this paper, we proposed a new method for the diagnosis of gastric diseases by automatically analyzing the hierarchical structure of gastric wall in gastric ultrasound images, which is helpful to quantify the diagnosis information of gastric diseases and is a useful attempt for early screening of gastric cancer. We designed a gastric wall detection network based on U-net. On this basis, anisotropic diffusion technology was used to extract the layered structure of the gastric wall. A simple and useful gastric cancer screening model was obtained by calculating and counting the thickness of the five-layer structure of the gastric wall. The experimental results showed that our model can accurately identify the gastric wall, and it was found that the layered parameters of abnormal gastric wall is significantly different from that of normal gastric wall. For the screening of gastric disease, a statistical model based on gastric wall stratification can give a screening accuracy of 95% with AUC of 0.92.

Mist1 Inhibits Epithelial-Mesenchymal Transition in Gastric Adenocarcinoma via Downregulating the Wnt/β-catenin Pathway

As a secretory cell transcription factor, muscle intestine stomach expression 1 (Mist1) is associated with serous secretory cell development and gastric chief cell maturation. Here, we focus on the function of Mist1 in gastric adenocarcinoma carcinogenesis. Based on clinical data and a mouse model of gastric cancer, we found that Mist1 expression was reduced in gastric cancer. Then, we overexpressed Mist1 using a lentivirus system and found that overexpression of Mist1 could inhibit gastric cancer cell proliferation, migration and invasion in vitro. Additionally, in vivo, we assessed the function of Mist1 in a gastric cancer xenograft model and distant pulmonary metastasis model. Overexpression of Mist1 decreased tumour growth and distant metastasis in vivo, suggesting that Mist1 acts as a tumour suppressor in gastric carcinogenesis. Furthermore, Mist1 overexpression inhibited epithelial-mesenchymal transition (EMT) in gastric cancer by suppressing β-catenin transcription activity and then the Wingless and INT-1 (Wnt)/β-catenin signalling pathway, which could be reversed by a Wnt/β-catenin-specific agonist. In conclusion, this study indicated that overexpression of Mist1 could reverse EMT in gastric carcinogenesis by inhibiting the Wnt/β-catenin signalling pathway and that Mist1 might be a novel marker for early gastric cancer screening.

Screening for Early Gastric Cancer Using a Noninvasive Urine Metabolomics Approach.

Simple SummaryThere are currently no effective specific biomarkers for the screening of early gastric cancer. Recently, metabolomics has been used to profile small endogenous metabolites, demonstrating significant potential in the diagnosis/screening of cancer, owing to its ability to conduct a noninvasive sample analysis. Here, we performed a urine metabolomics analysis in the context of an early diagnosis of gastric cancer. This approach showed very high diagnostic sensitivity and specificity and performed significantly better than the analysis of serum tumor markers modalities. An additional genomic data analysis revealed the up-regulation of several genes in gastric cancer. This metabolomics-based early diagnosis approach may have the potential for mass screening an average-risk population and may facilitate endoscopic examination through risk stratification.The early detection of gastric cancer (GC) could decrease its incidence and mortality. However, there are currently no accurate noninvasive markers for GC screening. Therefore, we developed a noninvasive diagnostic approach, employing urine nuclear magnetic resonance (NMR) metabolomics, to discover putative metabolic markers associated with GC. Changes in urine metabolite levels during oncogenesis were evaluated using samples from 103 patients with GC and 100 age- and sex-matched healthy controls. Approximately 70% of the patients with GC (n = 69) had stage I GC, with the majority (n = 56) having intramucosal cancer. A multivariate statistical analysis of the urine NMR data well discriminated between the patient and control groups and revealed nine metabolites, including alanine, citrate, creatine, creatinine, glycerol, hippurate, phenylalanine, taurine, and 3-hydroxybutyrate, that contributed to the difference. A diagnostic performance test with a separate validation set exhibited a sensitivity and specificity of more than 90%, even with the intramucosal cancer samples only. In conclusion, the NMR-based urine metabolomics approach may have potential as a convenient screening method for the early detection of GC and may facilitate consequent endoscopic examination through risk stratification.

Diagnostic value of macrophage inhibitory cytokine 1 as a novel prognostic biomarkers for early gastric cancer screening.

BackgroundEarly diagnosis is very important to improve the survival rate of patients with gastric cancer (GC), especially in asymptomatic participants. However, low sensitivity of common biomarkers has caused difficulties in early screening of GC. In this study, we explored whether MIC‐1 can improve the detection rate of early GC.MethodsWe screened 8257 participants based on risk factors such as age, gender, and family history for physical examination including gastroscopy. Participant blood samples were taken for measure MIC‐1, CA‐199, CA72‐4, and PG1/PG2 levels. The diagnostic performance of MIC‐1 was assessed and compared with CA‐199, CA72‐4, and PG1/PG2, and its role in early GC diagnosis and the assessment of the risk of precancerous lesions have also been studied.ResultsBased on endoscopic and histopathological findings, 55 participants had GC, 566 participants had low‐grade neoplasia, and 2605 participants had chronic gastritis. MIC‐1 levels were significantly elevated in GC serum samples as compared to controls (P < .001). The sensitivity of serum MIC‐1 for GC diagnosis was much higher than that of CA‐199 (49.1% vs 20.0%) with similar specificities. Moreover, receiver operating characteristic (ROC) curve analysis also showed that serum MIC‐1 had a better performance compared with CA‐199, CA72‐4, and PG1/PG2 in distinguishing early‐stage GC (AUC: 72.9% vs 69.5%, 67.5%, 44.0%, respectively).ConclusionsSerum MIC‐1 is significantly elevated in most patients with early GC. MIC‐1 can serve as a novel diagnostic marker of early GC and value the risk of GC.

A protocol of systematic review and meta-analysis of narrow band imaging endoscopy in detection of early gastric cancer.

Background:Early gastric cancer is the fifth common malignancy and the third leading cause of cancer death throughout the world. However, it is not clear how endoscopic screening for early gastric cancer affects incidence or mortality. We performed a systematic review and meta-analysis to evaluate the relationship between endoscopic screening for the mortality and incidence of early gastric cancer.Materials and methods:This protocol established in this study has been reported following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Web of Science, PubMed, EMBASE, and the Cochrane Library were searched for cohort and case-control studies in cases without early gastric cancer until March 31, 2020. We will use a combination of Medical Subject Heading and free-text terms with various synonyms to search based on the Eligibility criteria. Two investigators independently reviewed the included studies and extracted relevant data. The relative risk and 95% confidence intervals were used as effect estimate. I-square test, substantial heterogeneity, sensitivity analysis, and publication bias assessment will be performed accordingly. Stata 15.0 and Review Manger 5.3 are used for meta-analysis and systematic review.Results:The results will be published in a peer-reviewed journal.Conclusion:The results of this review will be widely disseminated through peer-reviewed publications and conference presentations. This evidence may also provide helpful evidence of whether endoscopic screening would reduce the mortality and incidence of early gastric cancer.PROSPERO registration number:CRD42020171053

Effects of Helicobacter pylori infection and interleukin 6 on the expression of ITIH4 in human gastric cancer cells.

BackgroundHuman inter-α-trypsin inhibitor heavy chain 4 (ITIH4) is an acute phase response protein that is positively regulated by interleukin-6 (IL-6), suggesting that ITIH4 can be used as an early serological biomarker of gastric cancer.MethodsThe mechanism of ITIH4 elevation in gastric cancer cells was investigated via Helicobacter pylori (H. pylori) with or without recombinant human interleukin-6 (rhIL-6) in human gastric cell line AGS cells. The messenger RNA (mRNA) expressions of ITIH4 and IL-6 in AGS cells were detected with real-time quantitative polymerase chain reaction (qPCR), while the expression of ITIH4 protein and IL-6 in AGS cells was detected with Western blot and enzyme-linked immunosorbent assay (ELISA) methods.ResultsWe found that the mRNA and protein expressions of ITIH4 started to increase synchronously at 3 hours (h), peaked at 12 h, and then declined to normal a level at 24 h in AGS cells after H. pylori infection. Interestingly, the expression patterns of ITIH4 were positively correlated to IL-6 expression levels. In the ITIH4 expression experiment with IL-6 administration, the expression level of ITIH4 began to increase at a concentration of 6.25 ng/mL with rhIL-6 administration, reach a peak, and plateau at a concentration of 25 ng/mL of rhIL-6. The expression patterns of ITIH4 in AGS cells induced by H. pylori infection were closely related to the infection of H. pylori and the level of IL-6.ConclusionsThe detection of ITIH4 and IL-6 during H. pylori infection may be useful for the screening of early gastric cancer.

Linked Color Imaging Can Improve Detection Rate of Early Gastric Cancer in a High-Risk Population: A Multi-Center Randomized Controlled Clinical Trial.

Early diagnosis of gastric cancer is difficult in China due to the lack of a valid method for endoscopic screening. Early gastric cancer, especially flat gastric cancer, lacks specific endoscopic features. Many cases appear to be similar to ordinary gastritis cases under normal white light endoscopy, which can lead to misdiagnosis. In order to find a new method to improve detection rate of early gastric cancer in China, we designed a trial to validate linked color imaging (LCI) for screening of early gastric cancer in a high-risk population, as compared to white light imaging (WLI). Subjects were randomly allocated to either the LCI + WLI or WLI group and then subjected to gastroscopy and all endoscopies were made after special preparation. All endoscopists had knowledge of this experiment. The main indicator was the rate of detection of gastric neoplastic lesions. The difference in the detection rate between the two groups is reported. The detection rate was 4.31% in the WLI group and 8.01% in the LCI + WLI group. This is a difference of 3.70% with a P value < 0.001 and an OR (95% CI) of 1.934 (1.362, 2.746). The lower limit of the 95% CI was greater than 0, and the superiority margin was 1%. The detection rate of gastric neoplastic lesions was higher in the LCI + WLI group than in the WLI group, LCI might be an effective method for screening early gastric cancer.

Hsa_circ_0065149 is an Indicator for Early Gastric Cancer Screening and Prognosis Prediction.

Circular RNAs (circRNAs) are an endogenous RNAs with a covalently closed cyclic structure. They have emerged recently as key regulators in the development and progression of human cancers. However, the clinical values of most circRNAs in gastric cancer (GC) are unknown. Hsa_circ_0065149, one of the dysregulated circRNAs in gastric carcinogenesis detected by circRNA microarray, was chose as a targeted circRNA in this study. We firstly enlarged sample size and identified the level changes of hsa_circ_0065149 among four stages of gastric tumorigenesis from healthy gastric mucosa, gastritis, intestinal metaplasia to GC. Then, the potential relationship between hsa_circ_0065149 expression levels and GC patients' clinicopathological factors was investigated. Moreover, the clinical significance of hsa_circ_0065149 in plasma exosomes and gastric juice were explored. Receiver operating characteristic (ROC) curve and Kaplan-Meier survival curve were constructed to evaluate diagnostic and prognostic values. Finally, bioinformatics analysis was performed to excavate the potential functions of hsa_circ_0065149. Hsa_circ_0065149 expression was only significantly down-regulated in gastric cancer, not changed among healthy gastric mucosa and gastritis intestinal metaplasia. Low hsa_circ_0065149 expression levels in GC tissues were significantly associated with tumor diameter (P= 0.034) and perineural invasion (P= 0.037). GC patients with low hsa_circ_0065149 levels had a much longer overall survival than those in high group (P= 0.020). More important, hsa_circ_0065149 levels were significantly decreased in plasma exosomes of early GC patients. As a screening biomarker for early GC, hsa_circ_0065149 in plasma exosomes has higher sensitivity and specificity than traditional clinical biomarkers. Bioinformatics analysis suggest that the abnormal expression of hsa_circ_0065149 may play an important role during gastric carcinogenesis. Those results indicate that hsa_circ_0065149 in exosmoes is an indicator for early GC screening and prognosis prediction.

Current status and thinking of screening of early gastric cancer

我国很多地区正逐步开展早期胃癌的筛查工作，作者回顾了日本和韩国开展早期胃癌筛查的情况及结果，分析我国筛查的现况，结合自身的实践体会，提出了我国开展胃癌筛查应该采取的策略和亟待解决的问题。

A Comparison between Three Serological Stratification About Early Screening of Gastric Cancer

Objective: This study aimed to compare the effect in early screening of gastric cancer among the ABC method, the new ABC method and new gastric cancer screening scoring system. Methods: The serological examination was first performed in all population groups, and endoscopic and pathological examinations were performed in the high-risk groups. The population was divided into the low-, middle-, and high-risk groups. The ratio of risk stratification and the detection rate of gastric cancer were compared among the three screening methods, and the consistency were evaluated. According the receiver operating characteristic (ROC) curvesi¼Œthe best critical value of gastrin-17 (G-17) and pepsinogen ratio (PGR) for the diagnosis of gastric cancer was calculated. Results: A total of 63,171 patients were included and endoscopic examination was conducted in 4611 patients, confirmed 50 patients with gastric cancer, including 44 with early gastric cancer. In the ABC methods, the detection of gastric cancer in the low-, middle-, and high-risk groups was 8(0.63%), 31(1.21%) 和11 (1.41%), respectively. In the new ABC methods, the detection of gastric cancer in the low-, middle-, and high-risk groups was 24(1.41%), 18(0.72%) 和 8(1.96%), respectively. In the new scoring system, the ratio of risk stratification in the low-, middle-, and high-risk groups was 17i(0.60%), 19(1.32%) 和14(3.92%), respectively. A pair-wise comparison showed poor consistency among the three screening methods. The positive rate of gastric cancer was significantly higher in the high-risk group compared with the other two groups in the new scoring system method. The areas under the curve of G-17 and PGR for the diagnosis of gastric cancer were 0.579 and 0.649, respectively. When PGR <3.89 and PGR <2.39 were the critical values, the incidence of the gastric cancer was found to be higher in the high-risk group compared with the other risk groups. Conclusions: Three screening methods have a poor consistency among. The new scoring system had a high value in early gastric cancer screening. The detection rate of early gastric cancer was higher in the high-risk group compared with the other two groups. Funding: National Natural Science Foundation of China(81673745); Traditional Chinese Medicine Science and Technology Program of Zhejiang Province of China (2016ZA089). Declaration of Interest: The authors have no conflicts of interest to declare. Ethical Approval: This study was approved by the Ethics Committee of the First Affiliated Hospital, Zhejiang Chinese Medical University.

Simultaneous detection of gastric cancer screening biomarkers plasma pepsinogen I/II using fluorescent immunochromatographic strip coupled with a miniature analytical device

Pepsinogen I (PG I) and pepsinogen II (PG II) are gastric disease-associated proteins that have been utilized as biomarkers for gastric cancer screening. However, the current methods for detecting PG I and PG II can barely satisfy the needs of mass screening, especially in remote areas. In this study, a rapid and sensitive fluorescent immunochromatographic test strip with a miniature analytical device (20.0 cm × 18.9 cm × 11.2 cm, 2.4 kg) was developed for the simultaneous determination of PG I and PG II in one sample in a single assay, which is promisingly suitable for the mass screening of gastric cancer. Under the optimum conditions, PG I and PG II concentrations as low as 2.6 ng/mL and 1.0 ng/mL could be detected in 15 min with only 7.5 μL plasma specimen, and no cross-reactivity was observed. The detection range was linear over 10.0–210.0 ng/mL for PG I and 3.0–63.0 ng/mL for PG II. The immunosensor also demonstrated high recoveries (93.6–110.8% for PG I and 95.4–110.4% for PG II) with low coefficient of variation (CV) (4.8–8.1% for PG I and 6.6–11.7% for PG II) when testing actual human plasma. The analyses by the proposed assay correlated well with those by ELISA of 30 spiked samples. The assay was finally applied to 30 clinical samples, and the results showed its clinical significance for the early screening of gastric cancer. Therefore, the assay proposed in this study provides a rapid, sensitive, and simultaneous detection strategy in the pepsinogen test, and the results indicated its potential capacity in the mass screening of gastric cancer.

Application of data mining methods to improve screening for the risk of early gastric cancer

BackgroundAlthough gastric cancer is a malignancy with high morbidity and mortality in China, the survival rate of patients with early gastric cancer (EGC) is high after surgical resection. To strengthen diagnosing and screening is the key to improve the survival and life quality of patients with EGC. This study applied data mining methods to improve screening for the risk of EGC on the basis of noninvasive factors, and displayed important influence factors for the risk of EGC.MethodsThe dataset was derived from a project of the First Hospital Affiliated Guangdong Pharmaceutical University. A series of questionnaire surveys, serological examinations and endoscopy plus pathology biopsy were conducted in 618 patients with gastric diseases. Their risk of EGC was categorized into low and high risk of EGC by the results of endoscopy plus pathology biopsy. The synthetic minority oversampling technique (SMOTE) was used to solve imbalance categories of the risk of EGC. Four classification models of the risk of EGC was established, including logistic regression (LR) and three data mining algorithms.ResultsThe three data mining models had higher accuracy than the LR model. Gain curves of the three data mining models were convexes more closer to ideal curves by contrast with that of the LR model. AUC of the three data mining models were larger than that of the LR model as well. The three data mining models predicted the risk of EGC more effectively in comparison with the LR model. Moreover, this study found 16 important influence factors for the risk of EGC, such as occupations, helicobacter pylori infection, drinking hot water and so on.ConclusionsThe three data mining models have optimal predictive behaviors over the LR model, therefore can effectively evaluate the risk of EGC and assist clinicians in improving the diagnosis and screening of EGC. Sixteen important influence factors for the risk of EGC were illustrated, which may helpfully assess gastric carcinogenesis, and remind to early prevention and early detection of gastric cancer. This study may also be conducive to clinical researchers in selecting and conducting the optimal predictive models.

Label-free detection of pepsinogen 1 and 2 by polyethylene coating Lamb microfluidic device

Early screening of gastric cancer is a critical importance for the improvement of patients’ survival rate. Here, a polyethylene coating Lamb (PE-Lamb) microfluidic device with immune layer for gastric cancer label-free detection was constructed. Two serum pepsinogen 1 (PG1) and pepsinogen 2 (PG2) biomarkers were applied to screen and predict the appearance of gastric cancer. Compared with enzyme-linked immunosorbent assay (ELISA), this method achieved a higher sensitivity and less time (40 min vs 120 min). The limit of detections (LOD) were reached 60 pg/mL for PG1 and 30 pg/mL for PG2, which have two orders of magnitude lower than traditional ELISA. The linearity coefficient indexes (R2) for PG1 and PG2 were 0.992 and 0.953 respectively, which is similar to that of ELISA. In addition, PG1 and PG2 mixed antigens sample with human serum was detected by PE-Lamb approach, and the frequency response showed high reproducibility and specificity. The results indicate that PE-lamb diagnostic technique is a novel and promising method for high-throughput screening and early diagnosis of gastric cancer.

The value of HP combined with serum CEA, CA72-4 and CA24-2 in early gastric cancer screening

Objective To investigate the value of Helicobacter pylori (HP), blood carcinoembryonic antigen (CEA), carbohydrate antigens 72-4 (CA72-4) and CA24-2 in the screening of gastric cancer. Methods The contents of HP, blood CEA, CA72-4 and CA24-2 in 50 healthy controls, 45 patients with benign gastric lesions and 70 patients with gastric cancer were detected. According to the number of positive cases, the positive rate of single detection and the positive rate of combined detection were calculated. Sensitivity, specificity, and accuracy of serum tumor markers were calculated according to HP single and combined detection. Results The positive rate of each individual detection and 4 joint detection in gastric cancer group was significantly different from that in the benign lesion group and the normal control group (P 0.05). The sensitivity, specificity and accuracy of HP, blood CEA, CA72-4, CA24-2 joint detection were significantly higher than single detection (P<0.05). Conclusions Joint detection was significantly better than single detection, and can significantly improve the detection rate of gastric cancer. Key words: Helicobacter pylori; Carcinoembryonic antigen; Antigens, tumor-associated, carbohydrate; Stomach neoplasms/DI

Cost-effectiveness analysis of different enhanced magnifying endoscopic technologies for early gastric cancer screening

Objective To assess and compare the cost-effectiveness of different enhanced magnifying endoscopic technologies for early gastric cancer screening in Chinese patients with focal gastric lesions. Methods Target population was Chinese patients over forty years old with focal gastric lesions. A decision-tree model was constructed to compare the costs and clinical effectiveness of different endoscopic technologies for early gastric cancer screening. The endoscopic technologies included conventional white light endoscopy(WLE), magnifying endoscopy enhanced with narrow-band imaging(ME-NBI), magnifying endoscopy enhanced by epinephrine(ME-EPI), magnifying endoscopy enhanced by indigo carmine(ME-IDC) and magnifying endoscopy enhanced by acetic acid-indigo carmine mixture(ME-AIM). The main outcomes were the number of detected early gastric cancer and precancerous lesions. Data for base analysis mainly came from research results of domestic multicenter, large-scale opportunistic screening for early gastric cancer. Sensitivity analysis was conducted by using one-way sensitivity analysis. Results The estimated clinical benefit was similar for the four different enhanced magnifying endoscopic technologies. However, the screening cost was lower when using ME-AIM. ME-AIM had the best cost-effectiveness compared with three other technologies. The results showed morbidity of early gastric cancer in Chinese patients with early gastric cancer and precancerous lesions, the sensitivity and the cost of ME-AIM were the 3 main factors that influenced cost-effectiveness. Conclusion ME-AIM may be the most cost-effective for early gastric cancer screening in Chinese patients with focal gastric lesions. Key words: Stomach neoplasms; Cost-benefit analysis; Endoscopy, gastrointestinal; Early gastric cancer; Magnifying endoscopy