A machine learning model for predicting the lymph node metastasis of early gastric cancer not meeting the endoscopic curability criteria.

BACKGROUND: We developed a machine learning (ML) model to predict the risk of lymph node metastasis (LNM) in patients with early gastric cancer (EGC) who did not meet the existing Japanese endoscopic curability criteria and compared its performance with that of the most common clinical risk scoring system, the eCura system. METHODS: We used data from 4,042 consecutive patients with EGC from 21 institutions who underwent endoscopic submucosal dissection (ESD) and/or surgery between 2010 and 2021. All resected EGCs were histologically confirmed not to satisfy the current Japanese endoscopic curability criteria. Of all patients, 3,506 constituted the training cohort to develop the neural network-based ML model, and 536 constituted the validation cohort. The performance of our ML model, as measured by the area under the receiver operating characteristic curve (AUC), was compared with that of the eCura system in the validation cohort. RESULTS: LNM rates were 14% (503/3,506) and 7% (39/536) in the training and validation cohorts, respectively. The ML model identified patients with LNM with an AUC of 0.83 (95% confidence interval, 0.76-0.89) in the validation cohort, while the eCura system identified patients with LNM with an AUC of 0.77 (95% confidence interval, 0.70-0.85) (P = 0.006, DeLong's test). CONCLUSIONS: Our ML model performed better than the eCura system for predicting LNM risk in patients with EGC who did not meet the existing Japanese endoscopic curability criteria. We developed a neural network-based machine learning model that predicts the risk of lymph node metastasis in patients with early gastric cancer who did not meet the endoscopic curability criteria.

Efficacy of prophylactic clip closure in reducing the risk of delayed bleeding after colorectal endoscopic submucosal dissection in patients on anticoagulant therapy: Multicenter prospective study.

OBJECTIVES: The high rate of delayed bleeding after colorectal endoscopic submucosal dissection (ESD) in patients undergoing anticoagulant therapy remains a problem. Whether prophylactic clip closure reduces the rate of delayed bleeding in these patients is unclear. This study aimed to evaluate the efficacy of prophylactic clip closure in patients receiving anticoagulants. METHODS: This multicenter prospective interventional trial was conducted at nine referral centers in Japan. Patients regularly taking anticoagulants, including warfarin potassium or direct oral anticoagulants, and undergoing ESD for colorectal neoplasms were enrolled. The discontinuation of anticoagulants was minimized according to recent guidelines. After the ESD, post-ESD ulcers were prophylactically closed using endoclips. The primary end-point was the incidence of delayed bleeding. The sample size was 45 lesions, and prophylactic clip closure was considered effective when the upper limit of the 90% confidence interval (CI) for delayed bleeding did not exceed 20%. RESULTS: Forty-five lesions were used, and three were excluded. Complete closure was achieved in 41/42 lesions (97.6%). The overall delayed bleeding rate was low, at 4.9% (2/41; 90% [CI] 0.8-14.5), which was significantly lower than that at the prespecified threshold of 20% (P = 0.007). The median closure procedure time was 17 min, and the median number of clips was nine. No massive delayed bleeding requiring transfusion, interventional radiology, or surgery was observed, and no thromboembolic events were observed. CONCLUSION: Prophylactic clip closure may reduce the risk of delayed bleeding following colorectal ESD in patients receiving anticoagulants. TRIAL REGISTRATION: UMIN Clinical Trial Registry (UMIN000036734).

Endoscopic features and clinical course of colorectal carcinoma resected by cold snare polypectomy.

BACKGROUND AND AIM: Cold snare polypectomy is commonly performed to remove small colorectal polyps. Accidental resection of carcinomas during this procedure has been reported. Herein, we aimed to clarify the clinicopathological features and clinical course of colorectal carcinomas resected by cold snare polypectomy. METHODS: This multicenter retrospective cohort study was conducted at 10 Japanese healthcare centers. Of the colorectal lesions resected by cold snare polypectomy between April 2016 and March 2020, lesions pathologically diagnosed as carcinoma were reviewed. Centralized histology (based on the Vienna classification) and endoscopic reviews were performed. The study endpoints were endoscopic features and clinical outcomes of cold snare polypectomy-resected colorectal carcinomas (Vienna category ≥4.2). RESULTS: We reviewed 74 of the 70 693 lesions resected by cold snare polypectomy. After a central pathological review, 68 lesions were diagnosed as carcinomas. The Japan Narrow-band imaging Expert Team (JNET) classification type 2B, lesion size ≥6 mm, and multinodular morphology were the significant endoscopic predictors of carcinoma resected by cold snare polypectomy. No adverse events related to the procedure occurred. Sixty-three lesions were diagnosed as carcinomas within the mucosal layer, and 34 were curative resections. Of the five carcinoma lesions with submucosal invasion, additional surgery revealed remnant cancer tissues in one lesion. No local or metastatic recurrence was observed during follow-up. CONCLUSIONS: Although most of the carcinomas resected by cold snare polypectomy were within the mucosal layer, few lesions invading the submucosa were identified. Careful pre-procedural endoscopic evaluation, especially focusing on the JNET classification and multinodular morphology, is recommended.

Diagnostic value of endoscopic ultrasonography for the depth of gastric cancer suspected of submucosal invasion: a multicenter prospective study.

BACKGROUND: Although the combination of conventional endoscopy (CE) and endoscopic ultrasonography (EUS) is useful for predicting the depth of early gastric cancer (EGC), the diagnostic value of EUS for submucosal (SM) invasive cancer has not been fully investigated. METHODS: We conducted a multicenter prospective study from May 2017 to January 2021 to evaluate the validity of a diagnostic strategy combining CE and EUS and to clarify the additional value of EUS for EGC suspected of SM invasion. In each case, the diagnosis was first made using CE, followed by EUS, and finally confirmed using a combination algorithm. RESULTS: A total of 180 patients with EGC were enrolled from 10 institutions, of which 175 were analyzed. The histopathological depths were M, SM1, SM2, and ≥ MP in 72, 16, 64, and 23 lesions, respectively. Treatment included 92 endoscopic submucosal dissection cases and 83 surgical cases. The overall diagnostic accuracy classified by M-SM1 or SM2-MP was 58.3% for CE, 75.7% for EUS, and 78.9% for the combination of CE and EUS; the latter two were significantly higher than that of CE alone (P < 0.001). The CE, EUS, and combination accuracy rates in 108 differentiated-type lesions were 51.9%, 77.4%, and 79.6%, respectively; the latter two were significantly higher than CE alone (P < 0.001). A significant additive effect of EUS was observed in CE-SM2 low-confidence lesions but not in CE-M-SM1 lesions or in CE-SM2 high-confidence lesions. Among the nine CE findings, irregular surface, submucosal tumor-like elevation, and non-extension signs were significant independent markers of pSM2-MP. Poorly delineated EUS lesions were misdiagnosed. CONCLUSIONS: EUS provides additional value for differentiated-type and CE-SM2 low-confidence EGCs in diagnosing invasion depth. CLINICAL REGISTRATION NUMBER: UMIN000025862.

[Relationship between low back pain and physical activity and sitting time among community-dwelling older adults: A cross-sectional study].

Objectives　Japan has a high prevalence of low back pain among older adults requiring long-term care, which results in increasing expenses; therefore, prevention measures are necessary. This study aimed to examine the relationship between low back pain and physical activity and sitting time according to sex and age (65-74 years [young-old adults]; ≥75 years [old-old adults]) who had not received long-term care certification.Methods　A self-administered survey was mailed to 7,080 adults >65 years of age residing in Tsuru City (Yamanashi Prefecture, Japan) from January to February 2018, and had not received long-term care certification. Demographic information, health status (body mass index and medical history), lifestyle (dietary habits, alcohol consumption, and smoking), presence of low back pain, physical activity, sitting time, and social participation were measured. Low back pain was evaluated by asking, "Did you experience pain in parts of the body other than the knees for the past month?" Those who answered, "experienced low back pain" were categorized as "with low back pain". The short form of the International Physical Activity Questionnaire was used to assess physical activity, which was categorized into three groups: <150, 150-299, and ≥300 min/week. Sitting time was divided into two groups: <480 and ≥480 min/day. Multiple logistic regression analysis was used to determine the association between low back pain and physical activity and sitting time, according to sex and age.Results　Of the 7,080 individuals surveyed, 4,877 responded (2,217 male, 2,660 female), corresponding to a response rate of 68.9%. The number of older adults with low back pain was 1,542 (31.6%) including 673 (30.4%) males and 869 (32.7%) females. The rate of low back pain in young-old adults was 29.8% and 33.6% in old-old adults. There was no significant relationship between lower back pain and physical activity among the young-old adults. In the old-old adults, there was a significant relationship in the male ≥300 min group (odds ratio [OR] 0.66 [95%CI 0.48-0.89]), and in both female 150-299 (OR 0.69 [95%CI 0.48-0.99]) and ≥300 (OR 0.59 [95%CI 0.44-0.80]) min/week groups.Conclusion　The complaint rate for low back pain was approximately 30%, regardless of sex or age. These results suggest that interventions to prevent low back pain are necessary. Moreover, physical activity, but not sitting time, was associated with low back pain in both males and females among the old-old adults.

Local recurrence after endoscopic resection of sessile serrated lesions: A multicenter prospective study by the Osaka Gut Forum.

BACKGROUND AND AIM: Sessile serrated lesions (SSLs) act as precursors to colorectal cancer, sometimes harbor carcinomas, and are sometimes incompletely resected. We aimed to evaluate local recurrence after endoscopic resection of SSL ≥10 mm. METHODS: This prospective, single-arm, observational study was performed at eight Japanese tertiary institutions. Colorectal lesions ≥10 mm were resected endoscopically, and the pathological diagnosis was either an SSL or hyperplastic polyp (HP). Follow-up colonoscopy was performed 1 year later, and the local recurrence was evaluated by biopsy. RESULTS: From October 2018 to September 2021, 104 cases with 123 lesions were registered. Among the pathologically diagnosed 105 SSLs and 18 HPs, 95 and 7 lesions were diagnosed as SSLs and HPs, respectively, by central pathological review. Among the 104 endoscopically diagnosed SSLs, 86 were diagnosed as SSLs, whereas among the 11 endoscopically diagnosed HPs, two were diagnosed as HPs by central pathological review (the rest were SSLs). Among the 95 patients with 113 lesions who underwent follow-up colonoscopy, resection scars were identified in 95 (84%) lesions. Three (3.1%; 95% confidence interval 0.6-8.7%) local recurrences were diagnosed pathologically among 98 pathologically diagnosed SSLs. Two (6%) local recurrences were diagnosed in patients with SSLs ≥20 mm. CONCLUSIONS: The local recurrence rate after endoscopic resection of SSLs ≥10 mm was 3.1%. Careful follow-up is recommended after endoscopic resection of large SSLs. Endoscopically diagnosed HPs ≥10 mm were sometimes pathologically diagnosed as SSL and should be considered for resection.

Geriatric nutritional risk index as a prognostic indicator in elderly patients with early colorectal cancer undergoing endoscopic submucosal dissection.

OBJECTIVES: Data on the long-term outcomes of endoscopic submucosal dissection (ESD) performed in elderly patients with early colorectal cancer (CRC) are limited. We analyzed the prognosis of elderly CRC patients, not only from the viewpoint of treatment curability but also from the patients' baseline physical condition assessed by several indexes. METHODS: A retrospective analysis of 729 patients aged ≥75 years who underwent ESD for Tis/T1 CRC in 16 institutions was conducted. The patients were classified into three groups based on curability: curative ESD (Group A, n = 582), non-curative ESD with additional surgery (Group B, n = 60), and non-curative ESD without additional surgery (Group C, n = 87). Overall survival (OS) was compared among the groups, and factors associated with reduced OS were investigated. RESULTS: The median follow-up periods in Groups A, B, and C were 41, 49, and 46 months, respectively (P = 0.62), during which 92 patients died. Two patients (0.3%) in Group A, none (0%) in Group B, and three (3.4%) in Group C died of CRC. Three-year OS rates in Groups A, B, and C were 93.9%, 96.1%, and 90.1%, respectively, without a significant difference (P = 0.07). Multivariate analysis indicated low (<96.3) geriatric nutritional risk index (GNRI) as the sole independent predictor for reduced OS (hazard ratio 3.37; 95% confidence interval 2.18-5.22; P < 0.0001). CONCLUSIONS: Low GNRI, but not the curability attained by ESD, was independently associated with reduced OS in patients with early CRC aged ≥75 years.

[A case of eosinophilic gastroenteritis caused after the use of Seprafilm®].

Eosinophilic gastroenteritis is a fairly uncommon condition. It has been suggested that allergic reactions may have played a role in the development of this illness. The case of a 66-year-old woman who had a total hysterectomy due to a right ovarian tumor is described here. At this operation, a sodium hyaluronate carboxymethylcellulose bioresorbable membrane (Seprafilm®) was used. She was admitted to our hospital 47 days after the operation with abdominal pain. Laboratory data indicated elevated WBC (29450/µl) and eosinophilia (69.2%), and CT scan showed thickening of intestinal wall and ascites around there. Ascites cytology showed a significant increase of eosinophils (94.0%). She began taking oral steroids after being diagnosed with eosinophilic gastroenteritis, and her symptoms improved quickly. Despite the fact that Seprafilm® was thought to be a reliable and safe tool, it was suggested that a foreign body reaction to Seprafilm® could lead to eosinophilic gastroenteritis.

Boron-Doped Polycyclic π-Electron Systems with an Antiaromatic Borole Substructure That Forms Photoresponsive B-P Lewis Adducts.

Heteroatom doping is a powerful strategy to alter the electronic structure of polycyclic aromatic hydrocarbons (PAHs). Especially boron doping endows PAH scaffolds with electron-accepting character and Lewis acidic centers. Herein, we report that embedding a five-membered borole ring into a polycyclic skeleton imparts the π-system with antiaromatic character and thereby induces unique properties and behavior. A series of borole-embedded π-conjugated compounds were synthesized from teraryl precursors via a borylation/intramolecular electrophilic C-H borylation sequence. The obtained compounds exhibit planar structures with distorted geometries around the boron center and form columnar slipped face-to-face π-stacked structures. Among these compounds, a pyrene-fused derivative shows an intense emission with a high quantum yield in solution. This compound also exhibits high Lewis acidity, which reflects the antiaromatic character and strained structure of the borole substructure. This compound forms a Lewis acid-base adduct even with weakly Lewis basic phosphorus-containing polycyclic π-systems. Analyzing the crystal structure of the thus-obtained adduct revealed a complex between the boron- and phosphorus-embedded π-systems with a direct B-P dative bond. This complex undergoes photodissociation in the excited state and exhibits an emission exclusively from the base-free borole-embedded π-system.

Endoscopic resection of local recurrences of diminutive polyps by cold forceps polypectomy.

OBJECTIVES: Cold forceps polypectomy (CFP) is an effective treatment for diminutive colorectal polyps. However, polyps occasionally recur, and there is no consensus on their long-term clinical management. Therefore, we investigated the short- and long-term clinical outcomes of re-CFP for recurrent diminutive colorectal polyps. MATERIALS AND METHODS: This was a follow-up of a multicenter, prospective study investigating the clinical outcomes of diminutive colorectal polyps excised by CFP with narrowband imaging-enhanced endoscopy and jumbo forceps. We evaluated short-term outcomes of re-CFP and patients at 1-year follow-up post re-CFP for recurrent colorectal polyps to determine long-term recurrence rates. Additionally, complete resection rates, clinicopathological features, number of forceps bites, and rate of short-term adverse events managed by re-CFP were evaluated. RESULTS: At 1-year follow-up, local recurrence was identified in 18 patients from the original study. The mean size of local recurrent polyps was 1.5 ± 0.6 mm, and all recurrent lesions were < 3 mm. Re-CFP could successfully excise locally recurrent polyps in all cases. All recurrent lesions were low-grade adenomas; no adverse events were reported. Additionally, 16 of 18 patients were evaluated endoscopically at 2-year follow-up; no recurrence was observed. CONCLUSIONS: Recurrent lesions following initial CFP were small and pathologically benign, and re-CFP was an effective treatment.

Helicobacter pylori eradication prevents secondary gastric cancer in patients with mild-to-moderate atrophic gastritis.

BACKGROUND AND AIM: Whether Helicobacter pylori eradication prevents metachronous recurrence after endoscopic resection (ER) of early gastric cancer remains controversial. This multicenter retrospective study aimed to evaluate the long-term (> 5 years) effects of H. pylori eradication by stratifying patients' baseline degrees of atrophic gastritis. METHODS: A total of 483 H. pylori-positive patients who had undergone ER for early gastric cancer were divided into two groups-(i) those having undergone successful H. pylori eradication within 1 year after ER (eradicated group, n = 294) and (ii) those with failed or not attempted H. pylori eradication (non-eradicated group, n = 189). The cumulative incidences of metachronous gastric cancer between the two groups were compared for all patients, for patients with mild-to-moderate atrophic gastritis (n = 182), and for patients with severe atrophic gastritis (n = 301). RESULTS: During a median follow-up of 5.2 years (range 1.1-14.8), metachronous cancer developed in 52 (17.7%) patients in the eradicated group and in 35 (18.5%) patients in the non-eradicated group (P = 0.11, log-rank test). In patients with mild-to-moderate atrophic gastritis (111 and 71 in the eradicated and non-eradicated groups, respectively), the cumulative incidence of metachronous cancer was significantly lower in the eradicated group than that in the non-eradicated group (P = 0.03, log-rank test). However, no significant intergroup difference was observed in patients with severe atrophic gastritis (P = 0.69, log-rank test). CONCLUSIONS: Helicobacter pylori eradication had a preventive effect on the development of metachronous gastric cancer in patients with mild-to-moderate atrophic gastritis.

[Effect of an exercise program targeting knee pain on medical costs of elderly community-dwelling adults].

Objectives　The aim of this study was to examine the effect of an exercise program targeting knee pain on longitudinal medical costs (MC) of elderly community-dwelling adults.Methods　A community-based health program using specific exercises for improving knee pain was held from January to February, 2015. Twenty-eight individuals participated in the program (intervention group) and seventy individuals were selected from the respondents of a health and lifestyle survey by matching age, sex, and baseline value of severity of knee pain as a control group. Twenty individuals from the intervention group and twenty-nine from the control group were included in the final analysis. The changes in MC from 2014 to 2018 were compared between the two groups using a linear mixed-effects model.Results　The effect of the program on MC, estimated as a change from the baseline in 2014, showed a reduction of -5.6×103 yen/person (95% CI: -39.2-28.0) for the entire four-year period after the intervention. However, this difference was not significant. The changes in MC each year after the intervention were 9.3×103 yen/person (95% CI: -39.6-58.3) in 2015, -2.0×103 yen/person (95% CI: -44.4-40.5) in 2016, -10.3×103 yen/person (95% CI: -42.5-21.9) in 2017, and 8.2×103 yen/person (95% CI: -39.1-55.4) in 2018.Conclusion　The exercise program did not show a clear benefit in reducing the MC of elderly community-dwellers during the four years after the intervention. Further research with longer study durations and larger sample populations would be necessary to determine the effect of such intervention programs on MC.

Comparison of performances of artificial intelligence versus expert endoscopists for real-time assisted diagnosis of esophageal squamous cell carcinoma (with video).

BACKGROUND AND AIMS: Narrow-band imaging (NBI) is currently regarded as the standard modality for diagnosing esophageal squamous cell carcinoma (SCC). We developed a computerized image-analysis system for diagnosing esophageal SCC by NBI and estimated its performance with video images. METHODS: Altogether, 23,746 images from 1544 pathologically proven superficial esophageal SCCs and 4587 images from 458 noncancerous and normal tissue were used to construct an artificial intelligence (AI) system. Five- to 9-second video clips from 144 patients captured by NBI or blue-light imaging were used as the validation dataset. These video images were diagnosed by the AI system and 13 board-certified specialists (experts). RESULTS: The diagnostic process was divided into 2 parts: detection (identify suspicious lesions) and characterization (differentiate cancer from noncancer). The sensitivities, specificities, and accuracies for the detection of SCC were, respectively, 91%, 51%, and 63% for the AI system and 79%, 72%, and 75% for the experts. The sensitivity of the AI system was significantly higher than that of the experts, but its specificity was significantly lower. Sensitivities, specificities, and accuracy for the characterization of SCC were, respectively, 86%, 89%, and 88% for the AI system and 74%, 76%, and 75% for the experts. The receiver operating characteristic curve showed that the AI system had significantly better diagnostic performance than the experts. CONCLUSIONS: Our AI system showed significantly higher sensitivity for detecting SCC and higher accuracy for characterizing SCC from noncancerous tissue than endoscopic experts.

Endoscopic alterations in Peyer's patches in patients with ulcerative colitis: A prospective, multicenter study.

BACKGROUND AND AIM: Peyer's patches (PPs) play a major role in intestinal mucosal immunity; however, their role in ulcerative colitis (UC) is not well investigated. We evaluated endoscopic features of PPs on narrow-band imaging with magnifying endoscopy (NBI-ME) and investigated their association with clinical factors. METHODS: We prospectively recruited 105 patients with UC, 18 with Crohn's disease, 16 with disease control, and 33 healthy control subjects at three institutions from 2014 to 2017. NBI-ME images of the villi of PPs were evaluated according to the Villi Index, and patients were divided into the Villi Index low (L) and high (H) types. The 1-year sustained clinical remission rate was evaluated between L-type and H-type PPs in patients with UC. RESULTS: The proportions of patients with H-type PPs were significantly higher among UC, Crohn's disease, and disease control patients than among healthy control patients (P = 0.0125, 0.018, 0.0007). In UC, age, gender, endoscopic score, and extent of disease involvement were not significantly different between L-type and H-type PPs, whereas the sustained clinical remission rate was significantly higher in L-type PPs than in H-type PPs (88% [57/65] vs 65% [17/26], P = 0.019). Multivariate analysis revealed that the L type of PPs was a significant factor for sustained clinical remission (odds ratio 3.8, 95% confidence interval 1.1-12.9, P = 0.033). CONCLUSIONS: Patients with UC showed endoscopic alterations in PPs on NBI-ME, and highly altered appearance of PPs can be associated with a high risk of clinical relapse in patients with UC.

Application of artificial intelligence using convolutional neural networks in determining the invasion depth of esophageal squamous cell carcinoma.

OBJECTIVES: In Japan, endoscopic resection (ER) is often used to treat esophageal squamous cell carcinoma (ESCC) when invasion depths are diagnosed as EP-SM1, whereas ESCC cases deeper than SM2 are treated by surgical operation or chemoradiotherapy. Therefore, it is crucial to determine the invasion depth of ESCC via preoperative endoscopic examination. Recently, rapid progress in the utilization of artificial intelligence (AI) with deep learning in medical fields has been achieved. In this study, we demonstrate the diagnostic ability of AI to measure ESCC invasion depth. METHODS: We retrospectively collected 1751 training images of ESCC at the Cancer Institute Hospital, Japan. We developed an AI-diagnostic system of convolutional neural networks using deep learning techniques with these images. Subsequently, 291 test images were prepared and reviewed by the AI-diagnostic system and 13 board-certified endoscopists to evaluate the diagnostic accuracy. RESULTS: The AI-diagnostic system detected 95.5% (279/291) of the ESCC in test images in 10 s, analyzed the 279 images and correctly estimated the invasion depth of ESCC with a sensitivity of 84.1% and accuracy of 80.9% in 6 s. The accuracy score of this system exceeded those of 12 out of 13 board-certified endoscopists, and its area under the curve (AUC) was greater than the AUCs of all endoscopists. CONCLUSIONS: The AI-diagnostic system demonstrated a higher diagnostic accuracy for ESCC invasion depth than those of endoscopists and, therefore, can be potentially used in ESCC diagnostics.

Classification for invasion depth of esophageal squamous cell carcinoma using a deep neural network compared with experienced endoscopists.

BACKGROUND AND AIMS: Cancer invasion depth is a critical factor affecting the choice of treatment in patients with superficial squamous cell carcinoma (SCC). However, the diagnosis of invasion depth is currently subjective and liable to interobserver variability. METHODS: We developed a deep learning-based artificial intelligence (AI) system based on Single Shot MultiBox Detector architecture for the assessment of superficial esophageal SCC. We obtained endoscopic images from patients with superficial esophageal SCC at our facility between December 2005 and December 2016. RESULTS: After excluding poor-quality images, 8660 non-magnified endoscopic (non-ME) and 5678 ME images from 804 superficial esophageal SCCs with pathologic proof of cancer invasion depth were used as the training dataset, and 405 non-ME images and 509 ME images from 155 patients were selected for the validation set. Our system showed a sensitivity of 90.1%, specificity of 95.8%, positive predictive value of 99.2%, negative predictive value of 63.9%, and an accuracy of 91.0% for differentiating pathologic mucosal and submucosal microinvasive (SM1) cancers from submucosal deep invasive (SM2/3) cancers. Cancer invasion depth was diagnosed by 16 experienced endoscopists using the same validation set, with an overall sensitivity of 89.8%, specificity of 88.3%, positive predictive value of 97.9%, negative predictive value of 65.5%, and an accuracy of 89.6%. CONCLUSIONS: This newly developed AI system showed favorable performance for diagnosing invasion depth in patients with superficial esophageal SCC, with comparable performance to experienced endoscopists.

Local recurrence of diminutive colorectal polyps after cold forceps polypectomy with jumbo forceps followed by magnified narrow-band imaging: a multicenter prospective study.

BACKGROUND: Cold polypectomy has been increasingly used to remove diminutive colorectal polyps. We evaluated the local recurrence rate of diminutive polyps at the 1-year follow-up after cold forceps polypectomy (CFP). METHODS: In a prospective, multicenter, observational cohort study, patients with diminutive colorectal polyps ( ≤ 5 mm) were treated by CFP using jumbo forceps followed by magnified narrow-band imaging (NBI). Patients were assessed for local recurrence at 1-year follow-up. Risk factors associated with local recurrence were analyzed using logistic regression analysis. RESULTS: Overall, 955 lesions were resected in 471 patients who completed the 1-year follow-up. The endoscopic complete resection rate was 99.4 %. Immediate and delayed bleeding occurred in 0.8 % and 0.2 % of cases, respectively, with no perforations observed. Local recurrence occurred in 2.1 % of cases at the 1-year follow-up. Univariable analyses indicated that polyps > 3 mm (P < 0.01) and immediate bleeding (P = 0.04) were significantly associated with local recurrence. A trend was observed for patients ≥ 65 years (P = 0.06) and fractional resection (P = 0.09). Multivariable analyses confirmed that lesions > 3 mm were significantly associated with local recurrence (odds ratio 3.4, P = 0.02). CONCLUSIONS: CFP with jumbo forceps followed by NBI-magnified observation had a low local recurrence rate and is an acceptable therapeutic option for diminutive colorectal polyps. Although we recommend limiting the use of CFP with jumbo forceps to polyps ≤ 3 mm in size, future comparative studies are needed to make recommendations on cold polypectomy using either forceps or snares as the preferred approach for diminutive polyp resection.

Endoscopic Balloon Dilation Followed By Intralesional Steroid Injection for Anastomotic Strictures After Esophagectomy: A Randomized Controlled Trial.

OBJECTIVE: Endoscopic balloon dilation (EBD) is a standard treatment for anastomotic strictures after esophagectomy, and requires multiple dilations. We conducted a randomized controlled trial to assess the efficacy of adding a steroid injection to EBD to reduce restricture. METHODS: Patients were randomized to receive EBD combined with either triamcinolone or placebo injection. The primary endpoint was the number of dilations required to resolve the stricture. The secondary endpoints were restricture-free survival and adverse events. Patients with a dysphagia symptom score of ≥2 after esophagectomy with an endoscopy-confirmed anastomotic stricture were included. A total of 50 mg of triamcinolone acetonide (50 mg/5 mL) or an identical volume of normal saline solution as a placebo was injected per site using a 25-gauge needle immediately after EBD. Both the patient and treating physician were blinded to the treatment given. RESULTS: During the 4-year study period, 65 patients were randomized to either the steroid group (n = 33) or placebo group (n = 32). The median number of EBDs required to resolve strictures was 2.0 (interquartile range, 1.0-2.5) in the steroid group and 4.0 (interquartile range, 2.0-6.8) in the placebo group (p < 0.001). After 6 months of follow-up, 39% of patients who had received steroid injections remained recurrence free compared with 16% of those who had received saline injections (p = 0.002). No adverse events occurred during follow-up. CONCLUSIONS: Steroid injection shows promising results for the prevention of stricture recurrence in patients who underwent EBD for anastomotic strictures.

Highly Stereoselective Strecker Synthesis Induced by a Slight Modification of Benzhydrylamine from Achiral to Chiral.

2-Methylbenzhydrylamine is a chiral variant of achiral benzhydrylamine; however, the chirality formed from the small difference between the phenyl and o-tolyl groups is not expected to induce sufficient stereoselectivity in conventional homogeneous reactions. Initiated by the spontaneous formation and asymmetric amplification of the enantioenriched N-benzhydryl-α-aminonitrile forming conglomerate, we here report that (S)- and (R)-configured title amine, upon the Strecker reaction with achiral aldehydes and HCN, afford the corresponding α-aminonitriles with up to >99.5 % diastereomeric excess, in conjunction with an enhancement of chirality in the solid state. l-Alanine with 98 % ee was synthesized from the (S)-amine by using the method discussed here. Achiral aromatic and heteroaromatic aldehydes could also be successfully utilized to afford chiral α-aminonitriles in a highly stereoselective manner. The stereodivergent synthesis of styrylglycine nitriles has also been accomplished by using racemic and enantioenriched 2-methylbenzhydrylamine. Thus, accompanied with a small rearrangement of the common substrate from achiral toward chiral, the present reactions induce an enhancement of chirality, and expands the concept of stereoselective synthesis to increase the opportunity to access highly enantioenriched compounds such as α-amino acids.