Novel gastric endoscopic submucosal dissection training model enhances the endoscopic submucosal dissection skills of trainees: a multicenter comparative study

BACKGROUND

Endoscopic submucosal dissection (ESD) requires high endoscopic technical skills, and trainees should develop effective training methods. In collaboration with KOTOBUKI Medical, we developed the G-Master, which is a non-animal training model that can simulate various parts of gastric ESD. We aimed to clarify the usefulness of the G-Master for inexperienced ESD trainees.

METHODS

We collected data from the first 5 gastric ESD cases conducted by 15 inexperienced ESD trainees at 5 participating centers between 2018 and 2022. The participants were divided into two groups: the G-Master training and non-G-Master training groups. Outcome measurements, such as procedural speed, perforation rate, self-completion rate, and en bloc resection rate, were compared between the two groups retrospectively.

RESULTS

A total of 75 gastric ESD cases were included in this study. The G-Master training group included 25 cases performed by 5 trainees, whereas the non-G-Master training group included 50 cases performed by 10 trainees. The median procedural speed for all cases was significantly faster in the G-Master training group than in the non-G-Master training group. Moreover, the procedural speed was linearly improved from the initial to the last cases in the lower location in the G-Master training group compared with the non-G-Master training group. In addition, although there was no significant difference, the G-Master training group showed lower rates of perforation and a lesser need to transition to expert operators than the non-G-Master training group.

CONCLUSION

The G-Master could improve the ESD skills of inexperienced ESD trainees.

Advanced diagnostic endoscopy in the upper gastrointestinal tract: Review of the Japan Gastroenterological Endoscopic Society core sessions

The Japan Gastroenterological Endoscopy Society (JGES) held four serial symposia between 2021 and 2022 on state-of-the-art issues related to advanced diagnostic endoscopy of the upper gastrointestinal tract. This review summarizes the four core sessions and presents them as a conference report. Eleven studies were discussed in the 101st JGES Core Session, which addressed the challenges and prospects of upper gastroenterological endoscopy. Ten studies were also explored in the 102nd JGES Core Session on advanced upper gastrointestinal endoscopic diagnosis for decision-making regarding therapeutic strategies. Moreover, eight studies were presented during the 103rd JGES Core Session on the development and evaluation of endoscopic artificial intelligence in the field of upper gastrointestinal endoscopy. Twelve studies were also discussed in the 104th JGES Core Session, which focused on the evidence and new developments related to the upper gastrointestinal tract. The endoscopic diagnosis of upper gastrointestinal diseases using image-enhanced endoscopy and AI is one of the most recent topics and has received considerable attention. These four core sessions enabled us to grasp the current state-of-the-art in upper gastrointestinal endoscopic diagnostics and identify future challenges. Based on these studies, we hope that an endoscopic diagnostic system useful in clinical practice is established for each field of upper gastrointestinal endoscopy.

Investigation of vertical margin involvement in endoscopic resection for T1 colorectal cancer

OBJECTIVES

The resection of vertical margin-negative submucosally invasive colorectal cancer (CRC) relies on the pathological risk assessment of lymph node metastasis. However, no large-scale study has clarified the endoscopic resection (ER) outcome for submucosally invasive CRC, focusing on the vertical margin status. This retrospective study aimed to examine vertical margin involvement in ER for submucosally invasive CRC and explore the treatment consequences associated with vertical margin status.

METHODS

We analyzed 395 submucosally invasive CRC cases in 389 patients who underwent ER at our hospital between 2008 and 2020. The presence of residual tumors and simultaneous lymph node metastasis in patients who underwent additional surgery was assessed and compared between the vertical incomplete ER and the vertical margin-negative groups.

RESULTS

Among the patients, 270 were men, with a median age of 69 years. The vertical incomplete ER rate was 21.5%, with positive vertical margins and unclear vertical margins identified in 12.2% and 9.3% of the cases, respectively. Among 154 patients who underwent additional surgery after ER, the vertical incomplete ER group had a significantly higher residual tumor rate than the vertical margin-negative group (P = 0.001). The vertical incomplete ER group had a significantly higher lymph node metastasis rate than the vertical margin-negative group (P = 0.029).

CONCLUSION

This study clarified the substantial risk of vertical incomplete ER in submucosally invasive CRC and revealed the high risk of residual tumor and lymph node metastasis in vertical incomplete ER for submucosal CRC.

Novel cold snare technique with clipping for duodenal angioectasia

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Alcohol consumption, multiple Lugol-voiding lesions, and field cancerization

The development of multiple squamous cell carcinomas (SCC) in the upper aerodigestive tract, which includes the oral cavity, pharynx, larynx, and esophagus, is explained by field cancerization and is associated with alcohol consumption and cigarette smoking. We reviewed the association between alcohol consumption, multiple Lugol-voiding lesions, and field cancerization, mainly based on the Japan Esophageal Cohort study. The Japan Esophageal Cohort study is a prospective cohort study that enrolled patients with esophageal SCC after endoscopic resection. Enrolled patients received surveillance by gastrointestinal endoscopy every 6 months and surveillance by an otolaryngologist every 12 months. The Japan Esophageal Cohort study showed that esophageal SCC and head and neck SCC that developed after endoscopic resection for esophageal SCC were associated with genetic polymorphisms related to alcohol metabolism. They were also associated with Lugol-voiding lesions grade in the background esophageal mucosa, the score of the health risk appraisal model for predicting the risk of esophageal SCC, macrocytosis, and score on alcohol use disorders identification test. The standardized incidence ratio of head and neck SCC in patients with esophageal SCC after endoscopic resection was extremely high compared to the general population. Drinking and smoking cessation is strongly recommended to reduce the risk of metachronous esophageal SCC after treatment of esophageal SCC. Risk factors for field cancerization provide opportunities for early diagnosis and minimally invasive treatment. Lifestyle guidance of alcohol consumption and cigarette smoking for esophageal precancerous conditions, which are endoscopically visualized as multiple Lugol-voiding lesions, may play a pivotal role in decreasing the incidence and mortality of esophageal SCC.

Remarkable response as a new indicator for endoscopic evaluation of local efficacy of non-surgical treatments for esophageal cancer

In Japan, standard of care of the patients with resectable esophageal cancer is neoadjuvant chemotherapy (NAC) followed by esophagectomy. Patients unfitted for surgery or with unresectable locally advanced esophageal cancer are generally indicated with definitive chemoradiotherapy (CRT). Local disease control is undoubtful important for the management of patients with esophageal cancer, therefore endoscopic evaluation of local efficacy after non-surgical treatments must be essential. The significant shrink of primary site after NAC has been reported as a good indicator of pathological good response as well as favorable survival outcome after esophagectomy. And patients who could achieve remarkable shrink to T1 level after CRT had favorable outcomes with salvage surgery and could be good candidates for salvage endoscopic treatments. Based on these data, "Japanese Classification of Esophageal Cancer, 12th edition" defined the new endoscopic criteria "remarkable response (RR)", that means significant volume reduction after treatment, with the subjective endoscopic evaluation are proposed. In addition, the finding of local recurrence (LR) at primary site after achieving a CR was also proposed in the latest edition of Japanese Classification of Esophageal Cancer. The findings of LR are also important for detecting candidates for salvage endoscopic treatments at an early timing during surveillance after CRT. The endoscopic evaluation would encourage us to make concrete decisions for further treatment indications, therefore physicians treating patients with esophageal cancer should be well-acquainted with each finding.

Risk factors for intraoperative and delayed perforation related with gastric endoscopic submucosal dissection

BACKGROUND AND AIM

Perforation is one of the most important complications of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Several studies have examined risk factors for intraoperative and delayed perforations, but most were retrospective analyses with small numbers of patients.

METHODS

This study represents a secondary analysis of a Japanese multicenter prospective cohort study. We investigated the factors associated with each type of perforation using 9015 patients with 9975 EGCs undergoing ESD between July 2010 and June 2012.

RESULTS

Intraoperative perforation occurred in 198 patients (2.2%) with 203 lesions (2.0%), necessitating emergency surgery for four lesions (0.04% [2.0%, 4/203]). Delayed perforation occurred in another 37 patients (0.4%) with 42 lesions (0.4%), requiring emergency surgery for 12 lesions (0.12% [28.6%, 12/42]). Factors showing significant independent correlations with intraoperative perforation were upper or middle third of the stomach; remnant stomach or gastric tube; procedure time ≥100 min; tumor size >35 mm; body mass index (BMI) < 18.5 kg/m2; and ≥72 years. Factors showing significant independent correlations with delayed perforation were procedure time ≥60 min; BMI < 18.5 kg/m2; ≥75 years; ulceration; and tumor size >20 mm. Intraoperative perforation occurred most frequently at the greater curvature in the upper third of the stomach (7.9%), whereas delayed perforation occurred most frequently at the greater curvature in the middle third (1.2%).

CONCLUSION

This multicenter prospective cohort study clarified the risk and risk factors of intraoperative and delayed perforation related to ESD for EGCs, providing information to help endoscopists reduce perforation.

Listening evaluation of cochlear implant users: comparison of subjective and objective evaluation by visual analogue scale

OBJECTIVE

This study aimed to use short-form visual analogue scale cochlear implantation questionnaires to evaluate subjective aspects at each out-patient visit. The correlation between subjective hearing tests using the short-form visual analogue scale and objective hearing outcomes was evaluated.

METHOD

This study was conducted in a single centre. Cochlear implant users (n = 199) evaluated their hearing on a scale of 0 to 100 for the right, left and both ears. The Japanese speech perception test (CI-2004) Japanese monosyllable speech perception test (67-S) and cochlear implantation threshold were used for the objective cochlear implantation evaluation.

RESULTS

A significant correlation was found between the short-form visual analogue scale questionnaire and objective hearing outcome, for words (r = 0.64) and sentences (r = 0.62) in CI-2004 and 67-S (r = 0.56) tests. No significant correlation was found between the short-form visual analogue scale score and cochlear implantation threshold (r = -0.18).

CONCLUSION

Short-form visual analogue scale cochlear implantation questionnaires mean cochlear implant users spend less time answering subjective visual analogue scale questionnaires, and clinicians estimate a patient's cochlear implantation hearing and abnormality by chronological evaluation.

Prospective multicenter trial of the cryoballoon ablation system for superficial esophageal squamous cell carcinoma on the post-endoscopic resection scar. A CRYO-SCAR study (EPOC1902)

BACKGROUND AND AIMS

Endoscopic resection (ER) is a minimally invasive treatment for superficial esophageal squamous cell carcinoma (SESCC). Post-ER scars complicate en bloc resection, even with advanced techniques, such as endoscopic submucosal dissection. The cryoballoon ablation system (CBAS) effectively manages Barrett's esophagus but has limited evidence in SESCC treatment, particularly on post-ER scars. This study aimed to evaluate the efficacy and safety of the CBAS for treating SESCC on post-ER scars.

METHODS

This prospective study was conducted at two tertiary referral centers in Japan in patients endoscopically diagnosed with T1a SESCC on the post-ER scar. Focal CBAS was used for cryoablation, with specific criteria for lesion selection and treatment method. The primary endpoint was local complete response (L-CR) rate of the primary lesion 48 weeks after the first cryoablation as evaluated by an independent central evaluation committee.

RESULTS

From October 2020 to October 2021, 15 patients with 17 lesions underwent cryoablation, with two requiring repeat cryoablation. The L-CR rate for primary and all lesions evaluated by the central evaluation committee was 100%. The endoscopist's evaluation was consistent with these results. The median procedure time was 9 min. Eight patients experienced no pain, and the highest pain score reported on a numeric 1-10 rating scale was 3. The technical success rate was 94.7% (18/19). Throughout the median follow-up period of 14.3 months, recurrences, deaths, or severe treatment-related adverse events were not reported.

CONCLUSIONS

CBAS is a potentially safe and effective approach for SESCC on post-ER scars and represents an encouraging alternative to traditional endoscopic treatments.

Near-Infrared Fluorescence Imaging Sensor with Laser Diffuser for Visualizing Photoimmunotherapy Effects under Endoscopy

The drug efficacy evaluation of tumor-selective photosensitive substances was expected to be enabled by imaging the fluorescence intensity in the tumor area. However, fluorescence observation is difficult during treatments that are performed during gastrointestinal endoscopy because of the challenges associated with including the fluorescence filter in the camera part. To address this issue, this study developed a device that integrates a narrow camera and a laser diffuser to enable fluorescence imaging through a forceps port. This device was employed to demonstrate that a laser diffuser with an NIR fluorescence imaging sensor could be delivered through a 3.2 mm diameter port. In addition, fluorescence images of Cetuximab-IR700 were successfully observed in two mice, and the fluorescence intensity confirmed that the fluorescence decayed within 330 s. This device is expected to have practical application as a tool to identify the optimal irradiation dose for tumor-selective photosensitive substances under endoscopy.

Potential for expanding indications and curability criteria of endoscopic resection for early gastric cancer in elderly patients: results from a Japanese multicenter prospective cohort study

BACKGROUND AND AIMS

Evidence for endoscopic resection (ER) in elderly patients with early gastric cancer (EGC) is limited. We assessed its clinical outcomes, and explored new indications and curability criteria.

METHODS

We analyzed data from a Japanese multicenter prospective cohort study. Patients aged ≥75 years with EGC treated with ER were included. We classified "eCuraC-2 (corresponding to noncurative ER, defined in the Japanese gastric cancer treatment guidelines)" into "elderly-high (EL-H)" (>10% estimated metastatic risk) and "elderly-low (EL-L)" (≤10%).

RESULTS

In total, 3,371 patients with 3,821 EGCs were included; endoscopic submucosal dissection (ESD) was the prominent treatment choice. Among them, 3,586 lesions met the guidelines' ER indications and 235 did not. The proportions of en bloc and R0 resections and perforations were 98.9%, 94.4%, and 0.8%, respectively, in EGCs within the indications. In EGCs beyond the indications, they were 99.5%, 85.4%, and 5.9%, respectively, for lesions diagnosed as ≤3 cm, and 96.0%, 64.0%, and 18.0% for those >3 cm. Curative ER ("eCuraA/B") and EL-L were observed in 83.6% and 6.2% of lesions within the indications, respectively, and in 44.2% and 16.8% of lesions <3 cm beyond the indications, respectively. The 5-year cumulative gastric cancer death rates following eCuraA/B and EL-H were 0.3% (95% CI, 0.2-0.6) and 3.5% (2.0-5.7), respectively. Following EL-L, the rate was 0.9% (0.2-3.5) even without subsequent treatment.

CONCLUSIONS

Usefulness of ESD for elderly EGC patients was confirmed by their clinical outcomes. Lesions ≤3 cm and EL-L emerged as new ER indication and curability criterion, respectively.

Quantitative Analysis of the Concentration of Trifluridine in Tumor Hypoxic Regions Using a Novel Platform Combining Functional Endoscopy and Mass Spectrometry

Hypoxic regions in solid tumors are highly resistant to drugs and thus represents an obstacle in drug discovery. Currently, however, there are technical barriers in sampling human hypoxic tumors and examining drug delivery with high sensitivity and accuracy. Herein, we present a new platform combining functional endoscopy and highly sensitive liquid chromatography-mass spectrometry (LC-MS) to assess drug delivery to hypoxic regions. Because oxygen saturation endoscopic imaging (OXEI), a functional endoscopy, can evaluate lesions and hypoxia in real-time by simultaneously acquiring a pseudocolor map of oxygen saturation and conventional endoscopic images, this platform can be used to evaluate drug delivery with human samples from hypoxic regions. As the first clinical application of this platform, the relationship between hypoxic regions and the concentration of trifluridine (FTD) incorporated into DNA was evaluated in patients with advanced gastric cancer treated with FTD/tipiracil (FTD/TPI; n = 13) by obtaining and analysis of tissue samples by OXEI and LC-MS and vascular maturity index by CD31/α-SMA staining ex vivo. The results showed that the concentration of FTD was significantly higher in the normoxic region than in the hypoxic region (P < 0.05) and there were significantly more immature vessels in hypoxic regions than in normoxic regions (P < 0.05). These results indicate that the platform was sufficiently sensitive to evaluate differences in drug anabolism in different oxygenic regions of human tumor tissue. This new platform allows quantitative drug analysis in hypoxic regions and is expected to initiate a new era of drug discovery and development.

Association between continuous cessation or reduction of drinking alcohol and improvement of multiple dysplastic lesions in patients with esophageal squamous cell carcinoma after endoscopic resection

BACKGROUND

Multiple development of squamous cell carcinoma (SCC) in the upper aerodigestive tract has been explained by the 'field cancerization phenomenon' associated with alcohol drinking. Squamous dysplastic lesion is clinically visualised as a Lugol-voiding lesion (LVL) by chromoendoscopy. Whether cessation or reduction of alcohol drinking improves multiple LVL and reduces the risk of field cancerization has not been elucidated.

METHODS

We analysed 330 patients with newly diagnosed superficial esophageal SCC (ESCC) enrolled in the cohort study. The grade of LVL was assessed in all patients every 6 months. We instructed the patients to stop smoking and drinking and recorded their drinking and smoking status every 6 months.

RESULTS

Among 330 patients, we excluded 98 with no LVL or no drinking habit. Of the remaining 232 patients, 158 continuously ceased or reduced their drinking habit. Patients who ceased or reduced their drinking habit significantly showed improvement in the grade of LVL. Multivariate analysis showed that continuous cessation or reduction of drinking habit improved the grade of LVL (hazard ratio [HR] = 8.5, 95% confidence interval [CI] 1.7-153.8, p = 0.0053). Higher grade of LVL carried a high risk of multiple ESCC and head and neck SCC (HNSCC) (HR = 3.7, 95% CI 2.2-6.4, p < 0.0001). Improvement in LVL significantly decreased the risk of multiple ESCC and HNSCC (HR = 0.2, 95% CI 0.04-0.7, p = 0.009).

CONCLUSIONS

This is the first report indicating that field cancerization was reversible and cessation or reduction of drinking alcohol could prevent multiple squamous dysplastic lesion and multiple ESCC and HNSCC development.

CLINICAL TRIALS REGISTRY NUMBER

UMIN000001676.

Advancements in endoscopic management of small-bowel polyps in Peutz-Jeghers syndrome and familial adenomatous polyposis

Before the development of double-balloon enteroscopy (DBE), the standard management of small-bowel polyposis was surgical resection. This is an invasive procedure that could lead to short bowel syndrome. In the 21st century, several new enteroscopy techniques were distributed worldwide, including DBE, single-balloon enteroscopy, spiral enteroscopy, and motorized spiral enteroscopy. These devices enable the diagnoses and endoscopic interventions in the entire small bowel, even in patients with a history of laparotomy. In patients with Peutz-Jeghers syndrome (PJS), endoscopic ischemic polypectomy with clips or a detachable snare is the preferred method for managing pedunculated polyps because it is less likely to cause adverse events than conventional polypectomy. Although polyps in patients with PJS always recur, repeat endoscopic resection can reduce the total number and mean size of polyps in the long-term clinical course. Endoscopic reduction of small-bowel intussusception caused by PJS polyps can be successfully performed using DBE without surgery. A transparent hood is useful for securing a visual field during the treatment of small-bowel polyps, and minimal water exchange method is recommended to facilitate deep insertion. Familial adenomatous polyposis (FAP) is a genetic disorder that increases the risk of developing colorectal cancer. Because jejunal and ileal polyps in patients with FAP have the potential to develop into cancer via the adenoma-carcinoma sequence, periodical surveillance, and endoscopic resection are needed for them, not only polyps in the duodenum. In cases of multiple small-bowel polyps in patients with FAP, cold snare polypectomy without retrieval is an acceptable treatment option for polyps that are 10 mm or smaller in size. Additional good pieces of evidence are necessary to confirm these findings because this narrative review mostly includes retrospective observational studies from single center, case reports, and expert reviews.

Comprehensive single-cell analysis demonstrates radiotherapy-induced infiltration of macrophages expressing immunosuppressive genes into tumor in esophageal squamous cell carcinoma

Radiotherapy (RT) combined with immunotherapy is promising; however, the immune response signature in the clinical setting after RT remains unclear. Here, by integrative spatial and single-cell analyses using multiplex immunostaining (CODEX), spatial transcriptome (VISIUM), and single-cell RNA sequencing, we substantiated the infiltration of immune cells into tumors with dynamic changes in immunostimulatory and immunosuppressive gene expression after RT. In addition, our comprehensive analysis uncovered time- and cell type-dependent alterations in the gene expression profile after RT. Furthermore, myeloid cells showed prominent up-regulation of immune response-associated genes after RT. Notably, a subset of infiltrating tumor-associated myeloid cells showing PD-L1 positivity exhibited significant up-regulation of immunostimulatory (HMGB1 and ISG15), immunosuppressive (SIRPA and IDO1), and protumor genes (CXCL8, CCL3, IL-6, and IL-1AB), which can be targets of immunotherapy in combination with PD-L1. These datasets will provide information on the RT-induced gene signature to seek an appropriate target for personalized immunotherapy combined with RT and guide the timing of combination therapy.

Impact of a Time-Related Benchmark on the Adenoma Detection Rate in Surveillance Colonoscopy: A STROBE Statement-Oriented Cross-Sectional Cohort Study

BACKGROUND/AIMS

Colorectal adenomas are precursor lesions of globally increasing colorectal cancer. Hence, a high adenoma detection rate in colonoscopy is pivotal. We investigated the clinical impact of stratified colonoscopy observation time combined with observation time/intubation time ratio on the detection of colorectal adenomas.

MATERIALS AND METHODS

We conducted a single-center retrospective study including 369 consecutive patients who underwent colonoscopy following fecal immunochemical tests between May 2021 and April 2022. The primary outcome measure was the impact of the stratified observation time and observation time/ intubation time ratio (category 1: <6.0 minutes and <1.0, category 2: <6.0 minutes and ≥1.0, category 3: ≥6.0 minutes and <1.0, and category 4: ≥6.0 minutes and ≥1.0) on adenoma detection rate.

RESULTS

Cecum intubation was obtained in 367 patients (99.5%). Adenomas were detected in 226 patients (61.2%). From the univariate analysis, age ≥53 years, habitual alcohol intake, colonoscopy attachment (+), and observation time with observation time/intubation time ratio categories 3 and 4 were determined as significant factors for adenoma detection rate. From the logistic regression analysis, age ≥ 53 years (odds ratio: 4.86, 95% CI: 2.25-10.52), habitual alcohol intake (odds ratio: 2.26, 95% CI: 1.33-3.82), category 3 (odds ratio: 3.66, 95% CI: 1.81-7.45), and category 4 (odds ratio: 5.60, 95% CI: 2.92-10.73) were significant factors for adenoma detection rate.

CONCLUSION

We propose the observation time with observation time/intubation time ratio combined benchmark (with categories' thresholds based on observation time >6 minutes and scope withdrawal time exceeding intubation time [observation time/intubation time ratio > 1]) as a novel colonoscopy quality indicator. These findings represent an important educational message for endoscopists.

Metachronous primary gastric cancer after endoscopic resection in patients with esophageal squamous cell carcinoma

BACKGROUND

This study aimed to evaluate the risk factors for developing metachronous primary Gastric Cancer (GC) after Endoscopic Resection (ER) for esophageal Squamous Cell Carcinoma (SCC).

METHODS

We studied 283 patients with esophageal SCC who underwent ER. The study outcomes were as follows: (1) incidence of metachronous primary GC after ER; and (2) predictors for the development of metachronous primary GC after ER by the Cox proportional hazards model.

RESULTS

The median follow-up was 43.1 months (1.81-79.1), and the 3-year cumulative incidence of metachronous primary GC was 6.5% (95%CI: 4.1-10.4). The incidence of metachronous primary GC during the follow-up period was 2.31 per 100 person-years. The frequencies of severe gastric atrophy and macrocytosis at the timing of ER were significantly higher in patients with than without metachronous primary GC (91.7% vs. 73.2%, p = 0.0422, 20.8% vs. 5.2%, p = 0.0046, respectively). Severe gastric atrophy was associated with the development of metachronous primary GC (sex-and-age adjusted hazard ratio (HR) [95%CI] = 4.12 [0.95-27.78], p = 0.0093). Macrocytosis was associated with the development of metachronous primary GC (sex-and-age adjusted HR = 4.76 [1.75-13.0], p = 0.0012) and found to be an independent predictor for metachronous primary GC by multivariate Cox proportional hazards analysis (HR [95%CI] = 4.35 [1.60-11.84], p = 0.004).

CONCLUSIONS

Severe gastric atrophy and macrocytosis should be noted in the development of metachronous primary GC after ER for esophageal SCC. In particular, macrocytosis at the timing of ER was considered an important predictor.

CLINICAL TRIALS REGISTRY NUMBER

UMIN000001676.

Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

Superficial non-ampullary duodenal epithelial tumors now: endoscopic diagnosis and therapy

With the recent increase in the frequency of duodenal tumor detection, significant progress has been made in endoscopic diagnosis and treatment. Although the first guidelines were issued in Japan, patient treatment varies widely among institutions. There is a need for improving the quality of endoscopic diagnosis and more curative and safer treatments. Biopsy is the standard diagnostic method; however, the diagnostic accuracy of endoscopic biopsy is not so high. Therefore, the differentiation of superficial non-ampullary duodenal epithelial tumors from non-neoplastic lesions is being developed. The incidence of lymph node and distant metastases of duodenal epithelial tumors is extremely rare in intramucosal carcinomas, and they are considered good candidates for endoscopic treatment if the technical difficulties can be resolved. Adverse events associated with endoscopic treatment are greatly reduced at advanced facilities through novel resection and closure methods, and further improvements are expected in the future. Clarifying the risk of metastatic recurrence may lead to the development of more appropriate treatments and curative resection criteria.

The feasibility of post-photodynamic therapy salvage esophagectomy in patients with esophageal squamous cell carcinoma treated with definitive chemoradiotherapy

BACKGROUND

Photodynamic therapy (PDT) is a minimally invasive salvage treatment for local residual or recurrent lesions that persist after the definitive chemoradiotherapy (dCRT) of esophageal cancer. However, esophageal cancer persistence after PDT is associated with a poor prognosis. Although esophagectomy is a curative treatment option, few studies have evaluated its efficacy. Thus, this study aimed to evaluate the outcomes of salvage esophagectomy after PDT.

METHODS

14 patients who underwent salvage esophagectomy for residual or recurrent esophageal cancer after PDT between April 2006 and November 2022 at our institution, were enrolled. The short-term (e.g., blood loss, operative time, R0 rate, postoperative complications, and postoperative hospital stay) and long-term (e.g., overall survival [OS] and recurrence-free survival [RFS]) of salvage esophagectomy after PDT were evaluated retrospectively.

RESULTS

The median operative time and intraoperative blood loss were 355 min and 350 ml, respectively. Eight patients (57.1%) had postoperative complications of Clavien-Dindo grade II or more. The median postoperative hospital stay was 20.5 days. The 3-year OS and RFS rates were 23.5% (95% confidence interval [CI] 5.7-48.0) and 16.3% (95% CI 2.7-40.3), respectively. Seven patients with an R0 had significantly longer OS than the seven patients with R1 and 2 (p = 0.045). The 3-year OS rate for patients with R0 was 52.6%.

CONCLUSIONS

Although salvage esophagectomy after PDT carries certain risks, patients who achieved an R0 had a promising long-term prognosis. The location and size of the lesion may be critical factors in determining whether R0 can be achieved with salvage esophagectomy after PDT.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Transposable elements potentiate radiotherapy-induced cellular immune reactions via RIG-I-mediated virus-sensing pathways

Radiotherapy (RT) plus immunotherapy is a promising modality; however, the therapeutic effects are insufficient, and the molecular mechanism requires clarification to further develop combination therapies. Here, we found that the RNA virus sensor pathway dominantly regulates the cellular immune response in NSCLC and ESCC cell lines. Notably, transposable elements (TEs), especially long terminal repeats (LTRs), functioned as key ligands for the RNA virus sensor RIG-I, and the mTOR-LTR-RIG-I axis induced the cellular immune response and dendritic cell and macrophage infiltration after irradiation. Moreover, RIG-I-dependent immune activation was observed in ESCC patient tissue. scRNA sequencing and spatial transcriptome analysis revealed that radiotherapy induced the expression of LTRs, and the RNA virus sensor pathway in immune and cancer cells; this pathway was also found to mediate tumour conversion to an immunological hot state. Here, we report the upstream and ligand of the RNA virus sensor pathway functions in irradiated cancer tissues.

Immunohistochemistry and oxygen saturation endoscopic imaging reveal hypoxia in submucosal invasive esophageal squamous cell carcinoma

BACKGROUND

Hypoxic microenvironment is prominent in advanced esophageal squamous cell carcinoma (ESCC). However, it is unclear whether ESCC becomes hypoxic when it remains in the mucosal layer or as it invades the submucosal layer. We aimed to investigate whether intramucosal (Tis-T1a) or submucosal invasive (T1b) ESCC becomes hypoxic using endoscopic submucosal dissection samples.

METHODS

We evaluated the expression of hypoxia markers including hypoxia inducible factor 1α (HIF-1α), carbonic anhydrase IX (CAIX), and glucose transporter 1 (GLUT1) by H-score and vessel density by microvessel count (MVC) and microvessel density (MVD) for CD31 and α-smooth muscle actin (α-SMA) with immunohistochemical staining (n = 109). Further, we quantified oxygen saturation (StO2 ) with oxygen saturation endoscopic imaging (OXEI) (n = 16) and compared them to non-neoplasia controls, Tis-T1a, and T1b.

RESULTS

In Tis-T1a, cccIX (13.0 vs. 0.290, p < 0.001) and GLUT1 (199 vs. 37.6, p < 0.001) were significantly increased. Similarly, median MVC (22.7/mm2 vs. 14.2/mm2 , p < 0.001) and MVD (0.991% vs. 0.478%, p < 0.001) were markedly augmented. Additionally, in T1b, the mean expression of HIF-1α (16.0 vs. 4.95, p < 0.001), CAIX (15.7 vs. 0.290, p < 0.001), and GLUT1 (177 vs. 37.6, p < 0.001) were significantly heightened, and median MVC (24.8/mm2 vs. 14.2/mm2 , p < 0.001) and MVD (1.51% vs. 0.478%, p < 0.001) were markedly higher. Furthermore, OXEI revealed that median StO2 was significantly lower in T1b than in non-neoplasia (54% vs. 61.5%, p = 0.00131) and tended to be lower in T1b than in Tis-T1a (54% vs. 62%, p = 0.0606).

CONCLUSION

These results suggest that ESCC becomes hypoxic even at an early stage, and is especially prominent in T1b.

Efficacy of a novel self-assembling peptide gel for hemostasis in refractory neoplastic bleeding

Video 1Outline of how self-assembling peptide gel can be used ex vivo.

Computer-aided demarcation of early gastric cancer: a pilot comparative study with endoscopists

BACKGROUND

Precise area diagnosis of early gastric cancer (EGC) is critical for reliable endoscopic resection. Computer-aided diagnosis (CAD) shows strong potential for detecting EGC and reducing cancer-care disparities caused by differences in endoscopists' skills. To be used in clinical practice, CAD should enable both the detection and the demarcation of lesions. This study proposes a scheme for the detection and delineation of EGC under white-light endoscopy and validates its performance using 1-year consecutive cases.

METHODS

Only 300 endoscopic images randomly selected from 68 consecutive cases were used for training a convolutional neural network. All cases were treated with endoscopic submucosal dissection, enabling the accumulation of a training dataset in which the extent of lesions was precisely determined. For validation, 462 cancer images and 396 normal images from 137 consecutive cases were used. From the validation results, 38 randomly selected images were compared with those delineated by six endoscopists.

RESULTS

Successful detections of EGC in 387 cancer images (83.8%) and the absence of lesions in 307 normal images (77.5%) were achieved. Positive and negative predictive values were 81.3% and 80.4%, respectively. Successful detection was achieved in 130 cases (94.9%). We achieved precise demarcation of EGC with a mean intersection over union of 66.5%, showing the extent of lesions with a smooth boundary; the results were comparable to those achieved by specialists.

CONCLUSIONS

Our scheme, validated using 1-year consecutive cases, shows potential for demarcating EGC. Its performance matched that of specialists; it might therefore be suitable for clinical use in the future.

Evaluating the identification of the extent of gastric cancer by over-1000 nm near-infrared hyperspectral imaging using surgical specimens

Significance

Determining the extent of gastric cancer (GC) is necessary for evaluating the gastrectomy margin for GC. Additionally, determining the extent of the GC that is not exposed to the mucosal surface remains difficult. However, near-infrared (NIR) can penetrate mucosal tissues highly efficiently.

Aim

We investigated the ability of near-infrared hyperspectral imaging (NIR-HSI) to identify GC areas, including exposed and unexposed using surgical specimens, and explored the identifiable characteristics of the GC.

Approach

Our study examined 10 patients with diagnosed GC who underwent surgery between 2020 and 2021. Specimen images were captured using NIR-HSI. For the specimens, the exposed area was defined as an area wherein the cancer was exposed on the surface, the unexposed area as an area wherein the cancer was present although the surface was covered by normal tissue, and the normal area as an area wherein the cancer was absent. We estimated the GC (including the exposed and unexposed areas) and normal areas using a support vector machine, which is a machine-learning method for classification. The prediction accuracy of the GC region in every area and normal region was evaluated. Additionally, the tumor thicknesses of the GC were pathologically measured, and their differences in identifiable and unidentifiable areas were compared using NIR-HSI.

Results

The average prediction accuracy of the GC regions combined with both areas was 77.2%; with exposed and unexposed areas was 79.7% and 68.5%, respectively; and with normal regions was 79.7%. Additionally, the areas identified as cancerous had a tumor thickness of > 2    mm .

Conclusions

NIR-HSI identified the GC regions with high rates. As a feature, the exposed and unexposed areas with tumor thicknesses of > 2    mm were identified using NIR-HSI.

Curative Management After Endoscopic Resection for Esophageal Squamous Cell Carcinoma Invading Muscularis Mucosa or Shallow Submucosal Layer-Multicenter Real-World Survey in Japan

INTRODUCTION

Curative management after endoscopic resection (ER) for esophageal squamous cell carcinoma (ESCC), which invades the muscularis mucosa (pMM-ESCC) or shallow submucosal layer (pSM1-ESCC), has been controversial.

METHODS

We identified patients with pMM-ESCC and pSM1-ESCC treated by ER. Outcomes were the predictive factors for regional lymph node and distant recurrence, and survival data were based on the depth of invasion, lymphovascular invasion (LVI), and additional treatment immediately after ER.

RESULTS

A total of 992 patients with pMM-ESCC (n = 749) and pSM1-ESCC (n = 243) were registered. According to the multivariate Cox proportional hazards analysis, pSM1-ESCC (hazard ratio = 1.88, 95% confidence interval 1.15-3.07, P = 0.012) and LVI (hazard ratio = 6.92, 95% confidence interval 4.09-11.7, P < 0.0001) were associated with a risk of regional lymph node and distant recurrence. In the median follow-up period of 58.6 months (range 1-233), among patients with risk factors (pMM-ESCC with LVI or pSM1-ESCC), the 5-year overall survival rates, relapse-free survival rates, and cause-specific survival rates of patients with additional treatment were significantly better than those of patients without additional treatment; 85.4% vs 61.5% ( P < 0.0001), 80.5% vs 53.3% ( P < 0.0001), and 98.5% vs 93.1% ( P = 0.004), respectively. There was no difference in survival rate between the chemoradiotherapy and surgery groups.

DISCUSSION

pSM1 and LVI were risk factors for metastasis after ER for ESCC. To improve the survival, additional treatment immediately after ER, such as chemoradiotherapy or surgery, is effective in patients with these risk factors.

Clinical outcome of endoscopic-assisted transoral surgery for superficial cancer of pharyngo-esophageal junction

BACKGROUND

Endoscopic-assisted transoral surgery (TOS) for superficial cancer of the pharyngo-esophageal junction (PEJ) is risk of stricture, and therapeutic outcomes are unclear. This study aimed to evaluate clinical outcomes of endoscopic-assisted TOS for superficial PEJ cancers.

METHODS

We retrospectively compared clinical outcomes of endoscopic-assisted TOS for superficial PEJ cancers (group A) and of other sites in the hypopharynx (group B).

RESULTS

The group A comprised 12 lesions in 12 patients, and group B comprised 198 lesions in 146 patients. Group A and group B exhibited en bloc resection rates of 100% and 99%. Median operative times were 82 and 37 min (p < 0.001). The frequency of stricture and local recurrence in group A was significantly higher in group B (42% vs. 1%, p < 0.001; 25% vs. 6%, p = 0.036). All adverse events could be managed with conservative treatments.

CONCLUSIONS

Endoscopic-assisted TOS is not ideal for treating superficial PEJ cancers compared to other sites.

Hot snare polypectomy vs endoscopic mucosal resection using bipolar snare for intermediate size colorectal lesions: Propensity score matching

BACKGROUND

Endoscopic resection (ER) with bipolar snare, in which the electric current only passes through the tissue between the device’s two electrodes, is a prominent method used to prevent perforation due to electricity potentially. ER using bipolar snare with or without submucosal injection enabled safe resection of colorectal lesions measuring 10–15 mm in an ex vivo porcine model. ER with bipolar snare is expected to have good treatment outcomes in 10–15 mm colorectal lesions, with high safety even without submucosal injection. However, no clinical reports have compared treatment outcomes with and without submucosal injection.

AIM

To compare the treatment outcomes of bipolar polypectomy with hot snare polypectomy (HSP) to those with endoscopic mucosal resection (EMR).

METHODS

In this single-centre retrospective study, we enrolled 10–15 mm nonpedunculated colorectal lesions (565 Lesions in 463 patients) diagnosed as type 2A based on the Japan Narrow-band Imaging Expert Team classification, resected by either HSP or EMR between January 2018 and June 2021 at the National Cancer Center Hospital East. Lesions were divided into HSP and EMR groups, and propensity score matching was performed. In the matched cohort, en bloc and R0 resection rates and adverse events were compared between the two groups.

RESULTS

Of the 565 lesions in 463 patients, 117 lesions each in the HSP and EMR groups were selected after propensity score matching. In the original cohort, there was a significant difference in antithrombotic drug use (P < 0.05), lesion size (P < 0.01), location (P < 0.01), and macroscopic type (P < 0.05) between the HSP and EMR groups. In the matched cohort, the en bloc resection rates were comparable between both groups [93.2% (109/117) vs 92.3% (108/117), P = 0.81], and there was no significant difference in the R0 resection rate [77.8% (91/117) vs 80.3% (94/117), P = 0.64]. The incidence of delayed bleeding was similar in both groups [1.7% (2/117)]. Perforation occurred in the EMR group [0.9% (1/117)] but not in the HSP group.

CONCLUSION

Using bipolar snare, ER of nonpedunculated 10–15 mm colorectal lesions may be performed safely and effectively, even without submucosal injection.

Updates in the diagnosis and management of non-ampullary small-bowel polyposis

Advances in endoscopic instruments and techniques changed the strategy of diagnosis and management for non-ampullary small-bowel polyposis. In patients with Peutz-Jeghers syndrome, gastrointestinal surveillance using capsule endoscopy should commence no later than eight years old. Small bowel polyps >15 mm should be treated to prevent intussusception. Recently, endoscopic ischemic polypectomy and endoscopic reduction of intussusception were described. In patients with familial adenomatous polyposis, the first endoscopic screening using a lateral viewing and a longer endoscope to check the proximal jejunum should be performed around 25 years. Some experts recommend a first duodenal examination with a first colonoscopy (13 years). The surveillance intervals for duodenal polyposis should be adjusted individually. ESGE recommended the resection of every adenoma larger than 1 cm. Cold snare polypectomy has the potential to change the threshold of size for endoscopic resection. In patients with Juvenile polyposis syndrome, small bowel involvement seems infrequent and mostly located in the duodenal part. There is no indication for distal small bowel investigation.

Anatomical classification of pharyngeal and laryngeal endoscopic images using artificial intelligence

BACKGROUND

The entire pharynx should be observed endoscopically to avoid missing pharyngeal lesions. An artificial intelligence (AI) model recognizing anatomical locations can help identify blind spots. We developed and evaluated an AI model classifying pharyngeal and laryngeal endoscopic locations.

METHODS

The AI model was trained using 5382 endoscopic images, categorized into 15 anatomical locations, and evaluated using an independent dataset of 1110 images. The main outcomes were model accuracy, precision, recall, and F1-score. Moreover, we investigated focused regions in the input images contributing to the model predictions using gradient-weighted class activation mapping (Grad-CAM) and Guided Grad-CAM.

RESULTS

Our AI model correctly classified pharyngeal and laryngeal images into 15 anatomical locations, with an accuracy of 93.3%. The weighted averages of precision, recall, and F1-score were 0.934, 0.933, and 0.933, respectively.

CONCLUSION

Our AI model has an excellent performance determining pharyngeal and laryngeal anatomical locations, helping endoscopists notify of blind spots.

Maintenance of complete mucosal healing is associated with avoiding restenosis after endoscopic balloon dilation of Crohn's disease-related small intestinal strictures

Background

Endoscopic balloon dilation (EBD) is an effective, minimally invasive treatment for Crohn's disease (CD) related intestinal strictures. However, restenosis frequently occurs and requires repetitive EBD or surgical resection. Since previous studies could not evaluate restenosis based on stricture diameter, factors affecting restenosis after EBD were unclear. This study aimed to identify these factors by precisely measuring the diameter of small intestinal strictures in patients with CD.

Methods

This single-center retrospective study enrolled patients with CD with de novo small intestinal strictures who underwent two double-balloon enteroscopy sessions (EBD and follow-up) between January 2016 and October 2021. Clinical and endoscopic data were obtained from electronic medical records. A calibrated small-caliber-tip transparent hood was used to precisely measure stricture diameters. Multivariate analysis was performed to identify factors associated with restenosis.

Results

Forty-eight patients (37 male) were analyzed. The total number of strictures detected decreased from 162 to 143. The mean diameter of all strictures and the narrowest stricture in each patient increased significantly from 8.6 to 9.8 mm and from 7.6 to 8.7 mm, respectively. Thirty-two (67%) patients developed endoscopic restenosis. Multivariate analysis showed that the presence of ulcers at the follow-up session was a risk factor for restenosis (odds ratio 9.4, p = 0.01). Patients with complete mucosal healing at both sessions (n = 21) showed significant improvement in the narrowest stricture (+1.7 mm, p = 0.001).

Conclusions

Maintenance of complete mucosal healing is significantly associated with avoiding restenosis after EBD in CD-related small intestinal strictures.

Vonoprazan Therapy is as Effective for Functional Dyspepsia without Heartburn as Acotiamide Therapy

BACKGROUND AND AIMS

Acid suppression improves dyspepsia symptoms but the efficacy of vonoprazan for functional dyspepsia remains unclear. The aim of this study is to evaluate the effectiveness of vonoprazan therapy for functional dyspepsia without heartburn.

METHODS

Patients receiving vonoprazan 10 mg once daily or acotiamide 100 mg three times daily for more than one month were included and retrospectively reviewed. Functional dyspepsia was diagnosed based on the ROME IV criteria. Patients with heartburn were excluded. Eighty-five patients were divided into vonoprazan (n=48) and acotiamide (n=37) groups.

RESULTS

There were no significant differences at baseline between the vonoprazan and acotiamide groups. The functional dyspepsia score significantly improved in both groups (p<0.001). The degree of score reduction (55% vs 59%, p=0.559) and the resolution rates (21% vs 30%, p=0.345) were similar. Epigastric pain and postprandial distress scores were significantly improved in both groups, and the degree of improvement of each score was similar. Constipation and diarrhea scores were significantly improved in both groups, and the degree of improvement similar.

CONCLUSION

These preliminary results suggest that vonoprazan is effective for the treatment of functional dyspepsia without heartburn in the short-term, with results similar to acotiamide therapy.

Eosinophilic enteritis requiring differentiation from chronic enteropathy associated with SLCO2A1 gene: A case report

BACKGROUND

Eosinophilic gastrointestinal disease (EGID) is a disorder characterized by infiltration of eosinophils causing mucosal damage and dysfunction of the gastrointestinal tract. The endoscopic findings of eosinophilic enteritis (EoN), an EGID variant, are nonspecific and occasionally difficult to diagnose. In contrast, chronic enteropathy associated with SLCO2A1 (CEAS) is a chronic persistent small intestinal disorder characterized by endoscopic findings such as multiple oblique and circular ulcers.

CASE SUMMARY

We report the case of a 10-year-old boy who had suffered abdominal pain and fatigue for the preceding 6 mo. He was referred to our institute for investigation of suspected gastrointestinal bleeding because of severe anemia with hypoproteinemia and positive fecal human hemoglobin. The upper and lower gastrointestinal endoscopic findings were normal; however, double-balloon small bowel endoscopy showed multiple oblique and circular ulcers with discrete margins and mild constriction of the intestinal lumen in the ileum. The findings were highly consistent with CEAS, but urine prostaglandin metabolites were within normal limits, and no previously reported mutations in the SLCO2A1 gene were identified. Histological evaluation demonstrated moderate to severe eosinophilic infiltration localized to the small intestine suggesting a diagnosis of EoN. Clinical remission was maintained with montelukast and a partial elemental diet, but emergent surgery for bowel obstruction due to small intestinal stenosis was performed two years after the initial treatment.

CONCLUSION

EoN should be considered in the differential diagnosis of CEAS-like small intestinal ulcerative lesions and normal urinary prostaglandin metabolite levels.

Prospective study on the risk of transmission due to droplets and aerosols during an endoscopic procedure and the usefulness of extraoral suction devices

OBJECTIVES

Endoscopy poses a high risk of severe acute respiratory syndrome coronavirus 2 infection for medical personnel due to the dispersal of aerosols from the patient. We investigated the location and size of droplets generated during esophagogastroduodenoscopy (EGD) and endoscopic submucosal dissection (ESD), the contamination of the surrounding area before and after the procedures, and the effectiveness of using an extraoral suction device (Free arm arteo; TOKYO GIKEN, Inc., Tokyo, Japan).

METHODS

Patients who consented to the study and underwent EGD or ESD between December 8, 2020, and April 15, 2021, at the National Cancer Center East Hospital were included. Adenosine triphosphate (ATP) hygiene monitoring tests and a particle counter were used for measurements.

RESULTS

Assessments were performed on 22 EGD and 15 ESD cases. ATP hygiene monitoring tests showed significant elevations at three sites near the patient, and two sites 1.5 m away, for EGD, and at four sites near the patient and 1.5 m away for ESD. In both ESD and EGD, extraoral suction devices reduced the extent of the contamination. Particles <5 μm in size were generated during endoscopic procedures and dispersed from both the forceps hole and the patient's mouth. The extraoral suction device did not reduce the number of particles generated.

CONCLUSIONS

During endoscopic procedures, cleaning the surrounding environment is important in addition to standard precautions the endoscopist and caregivers take. The use of extraoral suction devices can also potentially reduce contamination of the surrounding environment.

Efficacy and safety of repeated endoscopic radial incision and cutting procedure for benign esophageal stricture

Background and study aims: Radial incision and cutting (RIC) is indicated for refractory benign esophageal strictures after curative treatment for esophageal cancer and has shown favorable short-term outcomes. However, re-stricture after RIC may occur in the long term, and RIC is performed repeatedly in such cases, but the efficacy and safety of repeated RIC are unclear. Therefore, we aimed to demonstrate the efficacy and safety of the repeated RIC for refractory benign esophageal strictures after surgical and non-surgical treatment. Patients and methods: Between April 2008 and September 2019, we enrolled patients who were treated with the first RIC for benign esophageal strictures. The RIC was indicated for the refractory stricture and repeatedly performed for re-refractory esophageal stricture after RIC. We retrospectively evaluated the 6-month refractory stricture-free rate, and adverse events (AEs) in the first RIC and repeated RICs. Results: Forty-six patients (39 men, 7 women; median age, 71 years, range 49-85) were included. RIC was performed once in 24 patients (non-repeated RIC group) and two or more times in 22 patients (repeated RIC group). In all patients, the 6-month refractory stricture-free rate after the first RIC were 42.3 %. In the repeated RIC group, the 6-month refractory stricture-free rate after the first and repeated RICs were 18.2 % vs 18.2 %, respectively. No AEs were noted. Conclusions: Repeated RIC could be effective in the short-term and safe even for patients with refractory benign esophageal stricture after the first RIC. However, it cannot be considered curative treatment for refractory stricture because of poor long-term results.

Complete response to definitive chemoradiotherapy in unresectable locally advanced esophageal squamous cell carcinoma

BACKGROUND

Although definitive chemoradiotherapy (CRT) is the standard therapy for patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), poor survival has been reported. Although the complete response (CR) rate is strongly correlated with good prognosis, the predictive factors for CR have not been elucidated.

METHODS

This registry study aimed to identify predictors of CR to definitive CRT in patients with unresectable locally advanced ESCC. "Unresectable" was defined as the primary lesion invading unresectable adjacent structures such as the aorta, vertebral body, and trachea (T4b), or the regional and/or supraclavicular lymph nodes invading unresectable adjacent structures (LNT4b).

RESULTS

Overall, 175 patients who started definitive CRT between January 2013 and March 2020 were included. The confirmed CR (cCR) rate was 24% (42/175). The 2-year progression-free survival (PFS) and overall survival (OS) rates of cCR cases vs. non-cCR cases were 59% vs. 2% (log-rank p < 0.001) and 90% vs. 31% (log-rank p < 0.001), with a median follow-up period of 18.5 and 40.5 months, respectively. Multivariate analysis of clinicopathological factors revealed that tumor length ≥ 6 cm [odds ratio (OR) 0.446; 95% CI 0.220-0.905; p = 0.025] was a predictor of cCR.

CONCLUSIONS

Favorable PFS and OS rates were observed in patients with cCR. Tumor length was a predictive factor for cCR.

Revision surgery in a middle-aged patient with pertrochanteric fracture nonunion due to wedge effect caused by cephalomedullary nail: A case report

Trochanteric femur fractures have traditionally been treated surgically with compression hip screws or cephalomedullary nails. With the increasing use of cephalomedullary nails, potential complications from this technique have surfaced. One of them is the potential for varus malreduction of trochanteric femur fractures, known as the "wedge effect", which is the distraction of fracture fragments generated during reamer and nail passage resulting in varus malalignment at the neck-shaft angle. Although trochanteric nonunion in the non-elderly is exceedingly rare, we experienced one such case after nailing due to the wedge effect that was subsequently successfully treated with a compression hip screw without bone grafting. Therefore, in the case of stable pertrochanteric fractures (AO/OTA 31A1) in younger patients, compression hip screw surgery may be the better choice of initial surgery to avoid later nonunion.

Long-term Survival After Endoscopic Resection For Gastric Cancer: Real-world Evidence From a Multicenter Prospective Cohort

BACKGROUND & AIMS

We aimed to clarify the long-term outcomes of endoscopic resection (ER) for early gastric cancers (EGCs) based on pathological curability in a multicenter prospective cohort study.

METHODS

We analyzed the long-term outcomes of 9054 patients with 10,021 EGCs undergoing ER between July 2010 and June 2012. Primary endpoint was the 5-year overall survival (OS). The hazard ratio for all-cause mortality was calculated using the Cox proportional hazards model. We also compared the 5-year OS with the expected one calculated for the surgically resected patients with EGC. If the lower limit of the 95% confidence interval (CI) of the 5-year OS exceeded the expected 5-year OS minus a margin of 5% (threshold 5-year OS), ER was considered to be effective. Pathological curability was categorized into en bloc resection, negative margins, and negative lymphovascular invasion: differentiated-type, pT1a, ulcer negative, ≤2 cm (Category A1); differentiated-type, pT1a, ulcer negative, >2 cm or ulcer positive, ≤3 cm (Category A2); undifferentiated-type, pT1a, ulcer negative, ≤2 cm (Category A3); differentiated-type, pT1b (SM1), ≤3 cm (Category B); or noncurative resections (Category C).

RESULTS

Overall, the 5-year OS was 89.0% (95% CI, 88.3%-89.6%). In a multivariate analysis, no significant differences were observed when the hazard ratio of Categories A2, A3, and B were compared with that of A1. In all the pathological curability categories, the lower limit of the 95% CI for the 5-year OS exceeded the threshold 5-year OS.

CONCLUSION

ER can be recommended as a standard treatment for patients with EGCs fulfilling Category A2, A3, and B, as well as A1 (UMIN Clinical Trial Registry, UMIN000005871).

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande

We report a search for cosmic-ray boosted dark matter with protons using the 0.37  megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1  MeV/c^{2} to 300  MeV/c^{2}.

Multi-institutional questionnaire on treatment strategies for superficial entire circumferential esophageal squamous cell carcinoma

Objectives

Recent innovations in prophylactic treatment with steroids have overcome the issue of esophageal stricture after endoscopic submucosal dissection (ESD), except in entire circumferential esophageal squamous cell carcinoma (EC-ESCC). Current Japanese guidelines weakly recommend performing ESD for clinical epithelial/lamina propria EC-ESCC with a longitudinal extension <50 mm upon implementing prophylactic treatment against stricture. However, the accurate indications for ESD in EC-ESCC remain unknown, and strategies differ among institutions. The aim of this study was to understand the initial treatment strategy for EC-ESCC and prophylactic treatment after ESD against esophageal stricture.

Methods

A questionnaire survey was conducted across 16 Japanese high-volume centers on the initial treatment for EC-ESCC according to the invasion depth and longitudinal extension, and prophylactic treatment against stricture.

Results

ESD was performed as the initial treatment not only in clinical epithelial/lamina propria lesions <50 mm (88-94% of institutions), but also in clinical epithelial/lamina propria ≥50 mm (44-50% of institutions) and clinical muscularis mucosae/SM1 (submucosal invasion depth invasion within 200 μm) lesions <50 mm (56-75% of institutions). Regarding prophylactic treatment against esophageal stricture, although there was a common point of local steroid injection, the details and administration of other treatments varied among institutions.

Conclusions

As ESD was performed with expanded indications for EC-ESCC than those recommended by the guidelines in more than half of the institutions, the validity of ESD for expanded EC-ESCC needs to be clarified. For that, it is necessary to prospectively collect short- and long-term outcomes after ESD and other treatments, including esophagectomy or chemoradiotherapy.

Usefulness of endoscopic ultrasound in predicting treatment efficacy of salvage endoscopic therapy for local failure after chemoradiotherapy for esophageal squamous cell carcinoma

BACKGROUND

Salvage endoscopic therapy, including endoscopic resection (ER) and photodynamic therapy (PDT), is effective for esophageal squamous cell carcinoma (ESCC) in local failure after chemoradiotherapy (CRT). Resection with pathologically vertical margin-negative (VM0) for ER and local complete response (L-CR) for PDT are important surrogate prognostic markers for each therapy's efficacy. We aimed to evaluate the usefulness of endoscopic ultrasound (EUS) in predicting the efficacy of salvage endoscopic therapy in local failure after CRT for ESCC.

METHODS

We included patients who underwent EUS followed by ER or PDT for local failure after CRT or radiotherapy for ESCC from 2006 to 2020. We evaluated EUS findings associated with VM0 resection for ER and L-CR for PDT, which included the status of the outermost part of the submucosal layer, tumor thickness, and tumor invasion length into the muscularis propria (MP) layer.

RESULTS

Thirty and 47 patients were enrolled into the ER and PDT groups, respectively. The VM0 resection rate in the ER group was 87% (26/30). The EUS findings associated with VM0 resection were tumor thickness < 2.3 mm (p = 0.01) and preserved hyperechoic line of the outermost part of the submucosa layer (p < 0.01). The L-CR rate in the PDT group was 69% (32/47). The EUS findings associated with L-CR were tumor thickness < 5.0 mm (p < 0.01) and tumor invasion length into the MP layer < 1.6 mm (p = 0.03).

CONCLUSIONS

EUS can be useful in predicting the efficacy of salvage endoscopic treatment for local failure after CRT for ESCC.

Endoscopic treatment of intussusception due to small intestine polyps in patients with Peutz-Jeghers Syndrome

Background and study aims  Intussusception caused by intestinal polyps in patients with Peutz-Jeghers syndrome usually requires laparotomy. Patients following successful endoscopic reduction using double-balloon endoscopy (DBE) have been reported. The aim of this study was to evaluate the feasibility of endoscopic treatment of intussusception. Patients and methods  We retrospectively reviewed patients who underwent DBE for intussusception due to small intestine polyps in patients with Peutz-Jeghers syndrome from January 2004 to June 2020. Results  Twenty-seven (antegrade 22, retrograde 5) DBEs were performed in 19 patients with 25 sites of intussusception identified during the study period. If the intussusception remained once the endoscope reached the site, endoscopic reduction of the intussusception was performed as needed (15 sites). Ultimately, endoscopic resections (8 sites) or ischemic polypectomies (16 sites) of the polyp causing the intussusception were completed at 24 sites. Only one site could not be treated endoscopically and was treated surgically. The final per-site and per-patient success rates of endoscopic treatment were 96 % (24/25) and 95 % (18/19) respectively. Two patients developed mild acute pancreatitis and one patient developed intussusception after the procedures, both of which were treated non-operatively. Conclusions  Endoscopic treatment of intussusception is feasible to avoid laparotomy in patients with Peutz-Jeghers syndrome.