Differentiating Gastrointestinal Stromal Tumors From Leiomyomas of Upper Digestive Tract Using Convolutional Neural Network Model by Endoscopic Ultrasonography.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) and leiomyomas are the most common submucosal tumors of the upper digestive tract, and the diagnosis of the tumors is essential for their treatment and prognosis. However, the ability of endoscopic ultrasonography (EUS) which could correctly identify the tumor types is limited and closely related to the knowledge, operational level, and experience of the endoscopists. Therefore, the convolutional neural network (CNN) is used to assist endoscopists in determining GISTs or leiomyomas with EUS. MATERIALS AND METHODS: A model based on CNN was constructed according to GoogLeNet architecture to distinguish GISTs or leiomyomas. All EUS images collected from this study were randomly sampled and divided into training set (n=411) and testing set (n=103) in a ratio of 4:1. The CNN model was trained by EUS images from the training set, and the testing set was utilized to evaluate the performance of the CNN model. In addition, there were some comparisons between endoscopists and CNN models. RESULTS: It was shown that the sensitivity and specificity in identifying leiomyoma were 95.92%, 94.44%, sensitivity and specificity in identifying GIST were 94.44%, 95.92%, and accuracy in total was 95.15% of the CNN model. It indicates that the diagnostic accuracy of the CNN model is equivalent to skilled endoscopists, or even higher than them. CONCLUSION: While identifying GIST or leiomyoma, the performance of CNN model was robust, which is highlighting its promising role in supporting less-experienced endoscopists and reducing interobserver agreement.

Efficacy of endoscopic ultrasound and endoscopic resection for esophageal schwannoma.

BACKGROUND: Esophageal schwannoma (ES) is a rare submucosal tumor, and its complete and safe resection is a topic that deserves special attention. AIM: This study aimed to investigate the clinical value of endoscopic ultrasound (EUS) in the diagnosis of ES and the clinical efficacy of endoscopic resection for ES. METHODS: The clinical data, endoscopic characteristics, endoscopic treatment, postoperative complications, immunohistochemical results, and follow-up records of patients with ES admitted to the Tianjin Medical University General Hospital from January 2012 to January 2022 were retrospectively analyzed. RESULTS: Under white-light endoscopy, 81.8% (9/11) of lesions were submucosal elevations, covering the normal esophageal epithelium. Two of the lesions with redness and erosive surface. Eight lesions (72.7%) appear on EUS originating from the muscularis propria were homogeneous or inhomogeneous hypoechoic signals. Two lesions were inhomogeneous hyperechoic originating from the submucosa or muscularis propria, respectively. One lesion was homogeneous hypoechoic originating from the submucosa. All lesions had no blood flow signals, cystic changes, or calcification, and were completely removed by submucosal tunnel endoscopic resection (STER) or endoscopic submucosal dissection (ESD). All patients did not experience serious adverse events as well as recurrence, metastasis, or cicatricial esophageal stenosis during the follow-up period. CONCLUSION: ES is a rare submucosal lesion, which endoscopic characteristics are difficult to distinguish from other esophageal submucosal tumors. Endoscopic resection can provide a minimally invasive and alternative treatment for ES.

Role of endoscopic ultrasound and endoscopic resection in the diagnosis and treatment of esophageal granular cell tumors.

BACKGROUND AND AIM: Diagnosis and complete resection of esophageal granular cell tumors (GCTs) is an area of concern. However, articles on endoscopic ultrasound (EUS) and endoscopic resection of esophageal granular cell tumors are few. To evaluate the role of endoscopic ultrasound and endoscopic resection in the diagnosis and treatment of esophageal granular cell tumors. METHODS: A retrospective analysis of 15 patients with esophageal granular cell tumors who underwent endoscopic ultrasound examination and endoscopic resection in our hospital was conducted. The clinical data, endoscopic ultrasound images, endoscopic treatment, pathological characteristics, postoperative complications and follow-up status of all patients were evaluated. Ten board-certified endoscopists independently evaluated the white light endoscopic images of the 15 patients (Test 1) and the endoscopic ultrasound images together with white light endoscopic images of the same patient set (Test 2). RESULT: Female patients accounted for 53.4% of the participants. The average age at the time of diagnosis was 49.13 ± 9.31 years old. Ten lesions (66.67%) showed hypoechoic signal, four lesions (26.67%) showed hyperechoic signal and one lesion showed medium signal. The diagnostic accuracy was significantly higher with Test 2(65.3% vs. 92.0%, p < .001). Complete endoscopic resection was performed in all the patients. No complications occurred in any of the patients. No esophageal stenosis, recurrence, or metastases was found in all patients during the follow-up period. CONCLUSION: The endoscopic ultrasound images of esophageal granular cell tumors have certain characteristics that help diagnose esophageal granular cell tumors. Endoscopic resection of esophageal granular cell tumors is an effective, safe and feasible treatment method.

Effect of esophageal muscle fibrosis on prognosis of per-oral endoscopic myotomy (POEM) in achalasia patients.

BACKGROUND AND AIMS: Although esophageal smooth muscle fibrosis of achalasia (AC) patients has been described, the role and mechanism remain unclear. The aim of this study was to evaluate the fibrosis in the distal esophageal muscle in patients with AC and explore its relationship with prognosis of per-oral endoscopic myotomy (POEM). METHODS: Lower esophageal sphincter (LES) muscle from forty patients undergoing POEM for AC were obtained at the time of surgery. Control specimens consisted of similar muscle taken from distal esophagectomy for gastric tumors. The muscle fibrosis were assessed by Masson staining and confirmed by immunohistochemistry for collagen I and III. The total number of eosinophil within the myenteric propria were counted. In addition, clinical data were obtained through electronic medical records. Statistical comparison between groups were made. RESULTS: A significantly higher proportion of fibrosis in AC as compared with controls (P = 0.000). Eosinophil count, TGF-ß1, collagen I, and III were higher than those of control (P = 0.000, P = 0.001, P = 0.011, and P = 0.002, respectively). TGF-ß1, collagen I, and III were positively correlated with eosinophil count (all P < 0.05). Furthermore, the proportion of severe LES fibrosis in patients who failed to respond to POEM two years after operation was higher than that in responders (P = 0.028). And, Eckardt score two years after POEM was also positively correlated with degree of fibrosis-related cytokines (all P < 0.05). CONCLUSION: Smooth muscle fibrosis was prominent in lower part of esophagus of AC and positively correlated with severity of symptoms two years after POEM. The fibrosis might be relevant to eosinophil infiltration and TGF-ß1. Further studies are required to more clearly delineate the mechanism of muscle fibrosis and its correlation with prognosis of therapy for this idiopathic disease.

Peroral endoscopic myotomy for the treatment of achalasia after failed pneumatic dilation.

BACKGROUND AND AIMS: POEM is a rescue endoscopic therapy for patients who had previously failed surgical or endoscopic treatment. However, data regarding its effectiveness after failed pneumatic dilation (PD) and its long-term effects are limited. We aimed to retrospectively investigate the long-term outcomes in patients who had undergone POEM after failed PD. METHODS: Data from 66 achalasia patients with a 2-year follow-up period were analyzed. Intraprocedural events were compared between the first POEM group (patients without prior-endoscopic intervention) and prior PD group (patients who had pre-POEM PD). Symptom evaluation, HRM and 24 h-pH DeMeester scores between the two groups were performed at 2 years after the POEM procedure. Muscularis externa samples were obtained from the lower esophagus using POEM to assess the muscle fibrosis with Azan-Mallory staining. RESULTS: POEM was successfully performed for all achalasia patients. During the 2-year follow-up period, the success rate of POEM was 96.15% (25/26) for patients with prior PD and 95% (38/40) with primary POEM. For patients with type II achalasia and who underwent prior PD, the post-procedure DeMeester score was higher compared to patients who underwent POEM only (P < 0.05). A larger number of patients who underwent primary POEM (27.50%, 11/40) complained of mild heartburn compared to patients who underwent POEM after PD (7.69%, 2/26) (P < 0.05). With regards to fibrosis, the majority of patients who underwent POEM only were classified as F-1 (45.00%, 18/40), while the majority of patients who underwent prior PD were classified as F-2 (42.3%, 11/26). The degree of fibrosis was significantly different between the two groups (P < 0.05). Both surgical time and prior PD were correlated with the degree of fibrosis (P < 0.05). CONCLUSIONS: Despite the technical challenges, pre-POEM endoscopic treatment does not impact the safety and efficacy of POEM in achalasia patients. Longer follow-up studies using larger cohorts are needed to determine long-term outcomes and complications of POEM.

An Animal Study of Implantation of an Esophageal Pacemaker Based on Per-Oral Endoscopic Myotomy Approach for Alleviation of Esophageal Peristalsis Disorders.

BACKGROUND To restore esophageal peristalsis of achalasia patients by sequenced electric stimulation, an appropriate method must be established to implant the electrodes and pacemaker safely and effectively. We combined POEM (per-oral endoscopic myotomy) and abdominal wall puncture in pigs in order to explore a feasible procedure for the implantation. MATERIAL AND METHODS Five healthy male pigs were used in the present study with the permission of the Ethics Committee of Tianjin Medical University General Hospital. The electrodes were implanted in esophageal submucosal tunnel by POEM with the end of the electrode deposited in the abdominal cavity using NOTES technique. A pacemaker was then positioned under the skin of the abdomen. Finally, the electrodes were connected with the pacemaker with the help of endoscopy in the abdominal cavity. Esophageal peristalsis of these pigs after implantation was monitored for esophageal intraluminal pressure changes using electronic gastroscopy and a high-resolution manometry (HRM). The observation lasted for 6 h. RESULTS The procedure was effective to implant the electrode and the pacemaker using POEM and NOTES techniques. The connection of the 2 devices was also successful. Esophageal intraluminal pressure changes after electrical stimulation were recorded using HRM. Vital signs of the pigs were stable during the 6-h follow-up. CONCLUSIONS From this small-sample, short follow-up animal study, it was found that the implantation of esophageal electrodes and pacemaker based on POEM and NOTES is feasible, safe, and effective. Nevertheless, there is urgent need for long-term follow-up to confirm or disprove the safety of the procedure.

Efficacy and safety of endoscopic submucosal dissection for gastrointestinal neuroendocrine tumors: a 10-year data analysis of Northern China.

Objective: Endoscopy is the main method to treat gastrointestinal neuroendocrine tumors (GI-NETs), but the specific indications are still controversial. We aim to investigate the clinical outcomes of GI-NETs patients who experienced endoscopic submucosal dissection (ESD). Methods: We retrospectively reviewed the clinical features and prognosis of 65 GI-NETs patients who underwent ESD between 2008 and 2018. Results: A total of 65 patients diagnosed with GI-NETs pathologically, bearing 75 lesions, were found by endoscopy incidentally for other symptoms. The locations of these lesions were stomach (n = 24), duodenal bulb (n = 4) and rectum (n = 47). The diameter of 75 tumors were as follows: size ≤ 1 cm (78.7%), 1 cm < size ≤ 2 cm (17.3%), 2 cm < size ≤ 3.5 cm (4.0%). Endoscopic ultrasonography (EUS) suggested that 72 lesions were confined to submucosa and 3 lesions invaded into muscularis propria. The rates of en bloc resection and complete resection were all 100% and the rates of intraoperative bleeding and perforation were 2.7% and 1.3%, respectively. None of the 65 patients had lymph nodes and distant metastasis during the period of study. Conclusion: For GI-NETs without lymph nodes and distant metastases, the lesion confined to submucosa with the diameter ≤1 cm is absolute indication of ESD. For rectal neuroendocrine tumors limited in submucosa with the diameter between 1 and 2 cm, and Type 1 gastric neuroendocrine tumors predicted to be T2, ESD should be prioritized to preserve gastrointestinal volume and function at initial treatment.

Submucosal tunneling endoscopic resection of large submucosal tumors originating from the muscularis propria layer in the esophagus and gastric cardia.

AIMS: The aim of this study was to evaluate the short-term complications of submucosal tunneling endoscopic resection (STER) for large submucosal tumors (SMTs) originating from the muscularis propria (MP) layer in the esophagus and gastric cardia. METHODS: We performed 286 cases of STER from September 2012 to December 2017. The clinical data of patients with SMTs originating from the MP layer of 3.0-7.0 cm, who underwent STER procedure at the endoscopy center of Tianjin Medical University General Hospital, were collected retrospectively. Epidemiological data, tumor location, tumor size, procedure-related parameters, complications, and follow-up were included. RESULTS: A total of 27 (9.4 % [27/286]) patients were large-size SMTs, with a mean age of 51.9 ±â€Š9.4 years. The male/female ratio was 19:8. Of the 27 SMTs, 23 were located in the esophagus and 4 in the gastric cardia. The mean tumor size was 4.0 ± 1.1 cm. The en bloc resection rate was 85.2 % (23/27), and the complete resection rate was 100 % (27/27). Intra-operative perforation occurred in 2 patients (7.4 %) and post-operative perforation occurred in 2 patients (7.4 %). No other complications were observed. The average cost of the procedure was $3357.99 ± $1171.60 per inpatient stay (including both the procedure and an additional inpatient stay). The mean follow-up time was 15 ±â€Š10.1 months. No recurrence and metastasis occurred during the follow-up period. CONCLUSIONS: There is low risk of STER for the large-sized SMTs in the esophagus and gastric cardia, and the most common complication occurred during or after the procedure is perforation.

Peroral endoscopic myotomy versus pneumatic dilation - result from a retrospective study with 1-year follow-up.

BACKGROUND AND AIMS: On the basis of lesser rates of major adverse events and a short-term efficacy as Heller's myotomy, there is a growing enthusiasm in favor of peroral endoscopic myotomy (POEM), whereas study comparing POEM and pneumatic dilatation (PD) is quite rare. The aim of this study was to evaluate the efficacy of POEM and PD in Chinese achalasia patients in a retrospectively designed study. METHODS: Patients with achalasia, who underwent either PD (n = 26) or POEM (n = 40) were retrospectively recruited from September 2010 through March 2016 at a single tertiary center. During the 1-year follow-up, clinical outcome and functional data of lower esophageal sphincter (LES) were recruited. Clinical symptoms were assessed by use of the Eckardt score. The primary outcome was therapeutic success (Eckardt score ≤ 3). Functional data of LES (4-second integrated relaxation pressure [4s-IRP], LES relax rate, and LESP) at baseline and 1 month after treatment were also evaluated. Data was analyzed by SPSS 13.0 version using a significance level of p < 0.05. RESULTS: The success rates were 24/26 (92.31 %), 25/26 (96.15 %), and 24/26 (92.31 %), respectively, with POEM, as compared with 35/40 (87.50 %), 29/40 (72.50 %), and 23/40 (57.50 %), respectively, with PD, 1 month, 3 months, and 1 year after treatment. Statistically significant difference was observed between the 2 therapies (at 3 months, Fisher's exact test, p = 0.01; at 1 year, Fisher's exact test, p < 0.0001). Compared with PD, the Eckardt score was lower with POEM 1 month, 3 months, and 1 year after treatment. More patients in POEM group reported gastroesophageal reflux symptoms (after 3 months 7/26 (26.92 %) vs. 2/40 (5.00 %), Fisher's exact test, p = 0.01; after 1 year 6/26 (19.23 %) vs. 1/35 (2.86 %), Fisher's exact test, p = 0.02). The postoperative 4s-IRP and LESP were both lower with POEM than with PD, respectively. Type I achalasia had a better response with POEM than with PD. CONCLUSION: In this retrospective analysis with 1-year follow-up, POEM presents with a higher success rate and more reflux symptoms compared with PD. Change on LES function after treatment may explain the outcome in part. Type I achalasia may respond better to therapies compared with type II.

External validation and improvement of LiFe score as a prediction tool in critically ill cirrhosis patients.

AIM: The LiFe (liver, injury, failure, evaluation) score, calculated according to arterial lactate, total bilirubin, and international normalized ratio (INR), is a novel score for risk prediction in intensive care unit (ICU) patients with cirrhosis. The present study aimed to externally validate and optimize the LiFe score for predicting outcomes in critically ill cirrhosis patients. METHODS: The study used the single-center database Medical Information Mart for Intensive Care-III (MIMIC-III) for analysis. A total of 536 critically ill cirrhosis patients from the MIMIC-III database were analyzed. Routine clinical and laboratory variables were included to compare survivors with non-survivors. The LiFe score was then regraded into three groups to calculate the optimal cut-off values. RESULTS: In-ICU mortality occurred in 169 (31.5%) of the patients. Survivor and non-survivor cohorts were similar in age, gender, and etiology of cirrhosis. Multivariate analyses of in-ICU mortality identified four independent variables: total bilirubin, creatinine, INR, and arterial lactate. An external validation of the LiFe score showed good accuracy for predicting in-ICU mortality with an area under the receiver operating characteristic curve of 0.708. In addition, a significant positive correlation exists between LiFe score and acute-on-chronic liver failure grade (r = 0.393, P < 0.001). A log-rank test comparing the strata of simplified LiFe scores found that in-ICU mortality rates were 16.8%, 27.7%, and 51.7%, respectively, among patients in the three simplified risk categories. CONCLUSIONS: The LiFe score, based on laboratory tests, can be useful as a preliminary and convenient scoring tool in a broad cohort of critically ill cirrhosis patients. Simplified risk categories to stratify patients into three groups improves its feasibility and generalizability for clinical application.

Is It Necessary to Intubate the Cecum to Examine the Whole Colorectum During Endoscopic Polypectomy?

BACKGROUND The official guidelines are unclear about whether endoscopic polypectomy should intubate the whole cecum or just intubate the location of the endoscopy inspection. Therefore, the objective of this study was to provide a new perspective of assisting endoscopists make better decisions and decrease the missing detection rate in clinical practice. MATERIAL AND METHODS We retrospectively reviewed records of 8923 patients who underwent endoscopic polypectomy, and 394 participants were included after screening by inclusion and exclusion criteria. We collected and analyzed data on the size, shape, and location of polyps and the clinical experience level of endoscopists in this retrospective study. RESULTS Among the 394 cases, 152 (38.6%) had additional lesions detected through the second endoscopic polypectomy after the first colonoscopy was performed, showing statistically significant differences between the missing group and non-missing group on actual polys (P<0.05). No significant differences were detected between the 2 groups (P>0.05) in age, sex, withdrawal time, and examination period. Regarding the location, 50.4% of the missing lesions were found on the relatively proximal colon of the detected polyps in the first colonoscopy. In addition, the level of experience of endoscopists was significantly different between the missing group and the non-missing group (P<0.05). CONCLUSIONS The characteristics of polyps and the level of endoscopist experience play important roles in the detection of polyps in the colorectum. Moreover, it may be necessary to intubate the cecum to examine the whole colorectum during endoscopic polypectomy.

Is integrated relaxation pressure a promising predictor of effectiveness of peroral endoscopic myotomy for achalasia?

BACKGROUND: Peroral endoscopic myotomy (POEM), first introduced in 2010, appears to be an effective therapy with few complications. This study aimed to find an optimal predictor of POEM outcome in achalasia. METHODS: We retrospectively assessed 89 patients diagnosed with achalasia who underwent POEM in General Hospital of Tianjin Medical University, from September 2012 to March 2015. Associations of Eckardt score with symptom duration, lower esophageal resting pressure, 4-second integrated relaxation pressure (4s-IRP), and maximum esophageal diameter were assessed before POEM. The most relevant data were progressively grouped to compare symptom improvement after POEM in 85 patients at 1 year follow-up. RESULTS: The most significant correlation was found between 4s-IRP and Eckardt score (p < 0.01). The 85 achalasia patients (1-year follow-up after POEM) were divided into 3 groups according to 4s-IRP values; patients with mean 4s-IRP of 25 - 34 mmHg exhibited significantly greater improvement of clinical symptoms compared with the remaining 2 groups (p < 0.05). No significant postoperative difference was noted between types I and II in all patients according to Chicago classification criteria. The 40 patients with 4s-IRP of 25 - 34 mmHg were further divided into 2 subgroups; the 28 patients with type II achalasia responded better to POEM than the 12 with type I disease (p < 0.05). CONCLUSIONS: 4s-IRP, together with achalasia subtypes, may predict treatment outcome after POEM. Patients with type II achalasia and 4s-IRP of 25 - 34 mmHg may experience more satisfactory remission after POEM.

Analysis of the learning curve for peroral endoscopic myotomy for esophageal achalasia: Single-center, two-operator experience.

BACKGROUND AND AIM: Peroral endoscopic myotomy (POEM) has emerged as an advanced technique for the treatment of achalasia, and defining the learning curve is mandatory. METHODS: From August 2011 to June 2014, two operators in our institution (A&B) carried out POEM on 35 and 33 consecutive patients, respectively. Moving average and cumulative sum (CUSUM) methods were used to analyze the POEM learning curve for corrected operative time (cOT), referring to duration of per centimeter myotomy. Additionally, perioperative outcomes were compared among distinct learning curve phases. RESULTS: Using the moving average method, cOT reached a plateau at the 29th case and at the 24th case for operators A and B, respectively. CUSUM analysis identified three phases: initial learning period (Phase 1), efficiency period (Phase 2) and mastery period (Phase 3). The relatively smooth state in the CUSUM graph occurred at the 26th case and at the 24th case for operators A and B, respectively. Mean cOT of distinct phases for operator A were 8.32, 5.20 and 3.97 min, whereas they were 5.99, 3.06 and 3.75 min for operator B, respectively. Eckardt score and lower esophageal sphincter pressure significantly decreased during the 1-year follow-up period. Data were comparable regarding patient characteristics and perioperative outcomes. CONCLUSION: This single-center study demonstrated that expert endoscopists with experience in esophageal endoscopic submucosal dissection reached a plateau in learning of POEM after approximately 25 cases.

Ligation-Assisted Endoscopic Enucleation for the Resection of Gastrointestinal Tumors Originating from the Muscularis Propria: Analysis of Efficacy and Facility.

BACKGROUND: Gastrointestinal tumors originating from the muscularis propria are believed to have the potential to progress to malignant tumors. The efficacy of 'pre-management' with elastic band or endoloop assistant ligation after initial submucosal dissection in endoscopic enucleation procedure of these tumors was investigated and evaluated. METHODS: The study included 21 patients with small gastric stromal tumors arising in the gastric muscularis propria as determined by endoscopy (endoscopic ultrasonography). A standard endoscope with a transparent cap attached to the tip was used. The cap was placed over the lesion, after incision of the surrounding tissue, maximum sustained suction was applied. Then the elastic band or endoloop was released around the base. Circumference resection was performed with clips strengthening the defect closure. RESULTS: The 22 gastrointestinal stromal tumors sloughed completely. The mean time required for the full-thickness resection was 48 min. Minor perforation occurred with metal clips closing the defect of the gastric wall. Follow-up ranged from 13 to 42 months, during which time no recurrence was observed postoperatively. CONCLUSIONS: The band or endoloop assistant endoscopic ligation technique is effective for the enucleation of deep gastric tumors. It may help avoiding disturbance the abdominal cavity hemostasis in traditional full-thickness enucleation procedure.

A feasibility study of a thermally sensitive elastin-like polypeptide for submucosal injection application in endoscopic resection in 3 animal models.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) can successfully resect large lesions en bloc by using a submucosal injection solution, but the cost of currently available submucosal injection solutions is not satisfactory. The authors' aim was to evaluate the feasibility and effectiveness of a thermally sensitive elastin-like polypeptide (ELP) used as submucosal injection solution in ESD. METHODS: We conducted an ex vivo study to determine the optimal concentration of ELPs in rabbits, an in vivo study to evaluate the effectiveness of mucosal elevation in rats, and a large animal study to confirm the feasibility of preclinical application by using conventional clinical procedure in pigs. RESULTS: ELP (500 µM) was proved to be the optimal injectable submucosal injection solution and elevated mucosa more efficiently than any control. The same concentration of ELP exhibited an equivalent effectiveness of mucosal elevation, the retention of the elevation, and minimal bleeding with sodium hyaluronate. The ESD procedure time with 500 µM ELP in a preclinical study with pigs was significantly shorter than with any other concentration of ELP and normal saline solution. CONCLUSIONS: Use of ELP as submucosal injection solution was feasible, with higher and longer-lasting elevation and fewer adverse events.

Comparison of particle mass and solid particle number (SPN) emissions from a heavy-duty diesel vehicle under on-road driving conditions and a standard testing cycle.

It is important to understand the differences between emissions from standard laboratory testing cycles and those from actual on-road driving conditions, especially for solid particle number (SPN) emissions now being regulated in Europe. This study compared particle mass and SPN emissions from a heavy-duty diesel vehicle operating over the urban dynamometer driving schedule (UDDS) and actual on-road driving conditions. Particle mass emissions were calculated using the integrated particle size distribution (IPSD) method and called MIPSD. The MIPSD emissions for the UDDS and on-road tests were more than 6 times lower than the U.S. 2007 heavy-duty particulate matter (PM) mass standard. The MIPSD emissions for the UDDS fell between those for the on-road uphill and downhill driving. SPN and MIPSD measurements were dominated by nucleation particles for the UDDS and uphill driving and by accumulation mode particles for cruise and downhill driving. The SPN emissions were ∼ 3 times lower than the Euro 6 heavy-duty SPN limit for the UDDS and downhill driving and ∼ 4-5 times higher than the Euro 6 SPN limit for the more aggressive uphill driving; however, it is likely that most of the "solid" particles measured under these conditions were associated with a combination release of stored sulfates and enhanced sulfate formation associated with high exhaust temperatures, leading to growth of volatile particles into the solid particle counting range above 23 nm. Except for these conditions, a linear relationship was found between SPN and accumulation mode MIPSD. The coefficient of variation (COV) of SPN emissions of particles >23 nm ranged from 8 to 26% for the UDDS and on-road tests.

Efficacy and safety of endoscopic submucosal dissection in treating gastric subepithelial tumors originating in the muscularis propria layer: a single-center study of 144 cases.

OBJECTIVE. Subepithelial tumors (SETs) in the stomach are usually considered benign. However, some do have potential for malignant transformation, especially when originating in the muscularis propria (MP). Our study aimed to evaluate the clinical efficacy and safety of endoscopic submucosal dissection (ESD) for gastric SETs originating in MP. MATERIAL AND METHODS. A total of 145 gastric MP SETs in 144 patients were treated by ESD between September 2008 and December 2012. Characteristics of patients and SETs, therapeutic outcomes, pathologic characteristics, complications and follow-up outcomes were evaluated. RESULTS. Among the 144 patients, 104 were female (72.22%) and 40 were male (27.78%), and the mean age was 55.75 ± 11.29 years (range 18-78 years). The mean size of the tumors determined by endoscopic ultrasound (EUS) was 15.14 ± 9.70 mm (range 3-50 mm). En bloc complete resection was achieved in 134 of 145 tumors, giving a complete resection rate of 92.41%. The final histopathologic diagnoses included 52 leiomyomas, 89 gastrointestinal stromal tumors, 3 neurogenic tumors and 1 lipoma. Perforations occurred in 21 patients (14.48%) and were endoscopically repaired with clips or nylon bands. Intraoperative bleeding occurred in seven patients (4.83%) and was corrected with argon plasma coagulation (APC) or hot biopsy forceps. No local recurrence or distant metastasis was detected during a mean follow-up of 19.14 ± 10.29 months (range 3-51 months). CONCLUSIONS. ESD appears to be an effective and safe treatment for gastric SETs originating in MP.

Endoscopic submucosal dissection of large gastrointestinal stromal tumors in the esophagus and stomach.

BACKGROUND AND AIM: Gastrointestinal stromal tumors (GISTs), the most common mesenchymal tumors of the digestive tract with potential for malignant transformation, are mainly treated by open surgery or laparoscopic resection. The aim of this retrospective study was to evaluate the clinical efficacy, safety, and feasibility of endoscopic submucosal dissection (ESD) for large-size (2-5 cm) GISTs in the esophagus and stomach. METHODS: A total of 31 patients with large-size GISTs in the esophagus (6 patients) and stomach (25 patients) underwent ESD between September 2008 and December 2011. Demographics, clinical data, therapeutic outcomes, complications, pathological characteristics, risk classification, and follow-up outcomes were recorded. RESULTS: ESD was successfully performed in 31 patients at age of 59.06 ± 7.23 years (range: 46-74). The mean time of the procedure was 70.16 ± 16.25 min (range: 40-105). Perforation for 2-10 mm occurred in six patients (19.35%) and was endoscopically repaired with clips or nylon bands, with no conversions to open surgery. Intraoperative bleeding occurred in three patients (9.68%) and was corrected with argon plasma coagulation or hot biopsy forceps. No mortalities occurred. The mean size of the resected tumors was 2.70 ± 0.72 cm (range: 2.0-5.0). Out of the 31 patients, 24 (77.42%) were at very low risk and 7 (22.58%) were at low risk. Positive rate of CD117, DOG-1, and CD34 were 83.87%, 12.90%, and 100%, respectively. A follow up for 14.29 ± 8.99 months (range: 3-39) showed no recurrence or metastasis. CONCLUSIONS: ESD appears to be an effective, safe, and feasible treatment for large-size GISTs in the esophagus and stomach.

Synchronous presentation of acute pancreatitis and splenomegaly with intussusceptions in Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome (PJS) is a rare, autosomal dominant inherited disorder characterized by gastrointestinal hamartomatous polyps and pigmented mucocutaneous lesions. Intussusceptions and gastrointestinal tract bleeding are frequent complications of PJS caused by larger polyps, but acute pancreatitis and splenomegaly are very rare. Previously, surgical intervention was the only curative modality despite the associated complications. In recent years, double-balloon enteroscopy (DBE) has become the alternative method as the ideal treatment. We report the case of a 20-year-old woman diagnosed with PJS, as she suffered from 4-day nausea and vomiting with acute abdominal pain, and clinically manifested acute pancreatitis, splenomegaly and duodenojejunal intussusceptions secondary to a huge proximal jejunal polyp (10 cm × 2 cm). We removed the polyp via DBE and found that the acute pancreatitis, splenomegaly and duodenojejunal intussusceptions were simultaneously ameliorated 2 days after treatment. Currently, the patient has been symptom free for 3 months after polypectomy. Acute pancreatitis, splenomegaly and intussusceptions can synchronously occur in PJS patients, and polypectomy via DBE is the effective treatment alternative to surgical intervention for this disease, thereby obviating some complications associated with the latter.

20-Year Trends in Detection Rates of Cardia Cancer via Endoscopic Surveillance in Tianjin, China: A Hospital-Based Study.

Background: To analyze the time trends in cardia cancer detection rates using endoscopic surveillance from 1999 to 2019 in a high-volume Chinese hospital. Methods: In this retrospective, single-center study, data were collected from the Endoscopy Center of the Department of Gastroenterology, Tianjin Medical University General Hospital, from 1999 to 2019. Cases of cardia cancer (n = 1567) were extracted from a database of patients who underwent endoscopy. Clinical and epidemiological characteristics of patients with cardia cancer were analyzed, including sex, age, and proportion of early gastric cancer and degree of tumor differentiation. The joinpoint regression method was used to identify change points in incidence trends. Annual percent change (APC) values, with 95% confidence intervals (CI), were calculated for time periods before and after change points. Results: Of the 343942 patients who underwent endoscopy during 1999-2009, 1567 (4.6%) were identified with cardia cancer. The overall cardia adenocarcinoma detection rate decreased significantly from 1999 to 2004 (APC = -37.3, 95% CI: -20.9, -6.4), followed by a relatively slower decline rate from 2004 to 2019 (APC = -7.7, 95% CI: -4.4, -7.6). The crude rate of detection of early cardia cancer could not be determined by joinpoint analysis. Rates of detection reduced significantly in patients aged 60-69 and 70-79 years (APC = -8.3, 95% CI: -9.8, -6.8 and APC = -7.3, 95% CI: -8.8, -5.8, respectively). The detection rate in males decreased rapidly from 1999 to 2004 (APC = -35.9, 95% CI: -18.2, 5.6, P < 0.05), while the decline rate was relatively slow from 2005 to 2019 (APC = -6.9, 95% CI: -3.4, -6.1, P < 0.05). Among females, the detection rates also decreased from 1999 to 2004 (APC = -21.2, 95% CI: -28.1, -13.7), but remained stable from 2007 to 2019 (APC = -3.8, 95% CI: -7.9, -0.5). Detection of poorly differentiated cardia cancer also declined from 2009 to 2019 (APC = -12.8, 95% CI: -15.3, -10.0). Conclusions: The detection rate of cardia cancer among gastric cancers has been stable from 2008 to 2019. The trend of detection rate of early cardia cancer showed no significant statistical meaning; hence, it remains necessary to carefully observe the cardia area during endoscopy examination.