Determining factors for dexmedetomidine sedation in endoscopic submucosal dissection for early-stage gastric cancer.

Background and Aim: Although no specific sedation recommendations exist in early-stage gastric cancer (ESGC) for endoscopic submucosal dissection (ESD), dexmedetomidine (DEX) is useful along with benzodiazepines and analgesics. Furthermore, DEX is used for endoscopic treatment requiring lengthy sedation. However, it is unclear which patients should be administered DEX. We examined the factors that determine when DEX should be added for sedation during ESD for ESGC. Methods: Of 316 patients undergoing ESD for ESGC at our hospital between January 2017 and December 2020, we examined 310 receiving intravenous anesthesia. Preoperative patient factors and treatment outcomes were retrospectively examined according to the sedation method. Results: Among patients with ESGC undergoing ESD at our hospital, DEX was more frequently used alongside sedation in men, those undergoing gastrectomy, those with a lesion diameter ≥20 mm, and those with preoperative ulcers. In the standard group, patients whose treatment duration exceeded 120 min typically had a lesion diameter ≥20 mm, preoperative ulcers, lesions located outside the L region, and were treated by junior physicians. Conclusion: It is important to evaluate specific preoperative factors (lesion diameter ≥20 mm, preoperative ulcers, lesion located outside the L region, and having a junior physician as the treating physician) in patients undergoing ESD for ESGC to determine whether the combined use of DEX in sedation is necessary.

Using a novel hemostatic peptide solution to prevent bleeding after endoscopic submucosal dissection of a gastric tumor.

BACKGROUND: Endoscopic mucosal dissection has become the standard treatment for early gastric cancer. However, post-endoscopic submucosal dissection (ESD) ulcer occurs in 4.4% of patients. This study hypothesized whether applying PuraStat, a novel hemostatic peptide solution, prevents post-ESD bleeding. AIM: To investigate the preventive potential of PuraStat, a hemostatic formulation, against bleeding in post-ESD gastric ulcers. METHODS: Between May 2022 and March 2023, 101 patients (Group P) underwent ESD for gastric diseases at our hospital and received PuraStat (2 mL) for post-ESD ulcers. We retrospectively compared this group with a control group (Group C) comprising 297 patients who underwent ESD for gastric diseases at our hospital between April 2017 and March 2021. P values < 0.05 on two-sided tests indicated significance. RESULTS: Post-ESD bleeding occurred in 6 (5.9%) (95%CI: 2.8-12.4) and 20 (6.7%) (95%CI: 4.4-10.2) patients in Groups P and C, respectively, with no significant between-group difference. The relative risk was 1.01 (95%CI: 0.95-1.07). The lesser curvature or anterior wall was the bleeding site in all 6 patients who experienced postoperative bleeding in Group P. In multivariate analysis, the odds ratios for resection diameter ≥ 50 mm and oral anticoagulant use were 6.63 (95%CI: 2.52-14.47; P = 0.0001) and 4.04 (1.26-0.69; P = 0.0164), respectively. The adjusted odds ratio of post-ESD bleeding and PuraStat was 1.28 (95%CI: 0.28-2.15). CONCLUSION: PuraStat application is not associated with post-ESD bleeding. However, the study suggests that gravitational forces may affect the effectiveness of applied PuraStat.

Efficacy and Safety of a Novel Hemostatic Peptide Solution During Endoscopic Submucosal Dissection: A Multicenter Randomized Controlled Trial.

INTRODUCTION: To compare the effectiveness of the novel hemostatic peptide, TDM-621, with that of conventional hemostatic methods in treating intraoperative blood oozing during endoscopic submucosal dissection (ESD). METHODS: This multicenter, open-label, randomized controlled trial involved 227 patients with gastric and rectal epithelial tumors in whom ESD was indicated. Patients in whom the source of blood oozing was difficult to identify with waterjet washing during the procedure and required hemostasis with hemostatic forceps were randomly assigned to the TDM-621 and control groups. The TDM-621 group (in which hemostasis was achieved with TDM-621, followed by coagulation hemostasis with hemostatic forceps, as needed) was compared with the control group (in which hemostasis was achieved with hemostatic forceps). The primary end point was the mean number of coagulations with hemostatic forceps, determined by a blinded independent review committee. The secondary end points were the rate of achievement of hemostasis with only TDM-621, the dosage of TDM-621, and adverse events in the TDM-621 group. RESULTS: The mean number of coagulations with hemostatic forceps was significantly reduced in the TDM-621 group (1.0 ± 1.4) compared with that in the control group (4.9 ± 5.2) ( P < 0.001). The rate of hemostasis achievement with only TDM-621 was 62.2%; the mean dosage of TDM-621 was 1.75 ± 2.14 mL. The rates of grade ≥3 adverse events were 6.2% and 5.0% in the TDM-621 and control groups, respectively. DISCUSSION: TDM-621 is a useful, easily operable hemostatic peptide for treatment of blood oozing during gastric and rectal ESD, with no serious safety concerns.

Clinical practice guidelines for duodenal cancer 2021.

Duodenal cancer is considered to be a small intestinal carcinoma in terms of clinicopathology. In Japan, there are no established treatment guidelines based on sufficient scientific evidence; therefore, in daily clinical practice, treatment is based on the experience of individual physicians. However, with advances in diagnostic modalities, it is anticipated that opportunities for its detection will increase in future. We developed guidelines for duodenal cancer because this disease is considered to have a high medical need from both healthcare providers and patients for appropriate management. These guidelines were developed for use in actual clinical practice for patients suspected of having non-ampullary duodenal epithelial malignancy and for patients diagnosed with non-ampullary duodenal epithelial malignancy. In this study, a practice algorithm was developed in accordance with the Minds Practice Guideline Development Manual 2017, and Clinical Questions were set for each area of epidemiology and diagnosis, endoscopic treatment, surgical treatment, and chemotherapy. A draft recommendation was developed through a literature search and systematic review, followed by a vote on the recommendations. We made decisions based on actual clinical practice such that the level of evidence would not be the sole determinant of the recommendation. This guideline is the most standard guideline as of the time of preparation. It is important to decide how to handle each case in consultation with patients and their family, the treating physician, and other medical personnel, considering the actual situation at the facility (and the characteristics of the patient).

Excellent oncological outcomes besides short-term safety of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor.

Background and study aims Laparoscopic and endoscopic cooperative surgery (LECS) for gastric submucosal tumor was developed as a type of minimal local resection and is now widely used in Asian countries. However, the oncological safety of LECS for gastric gastrointestinal stromal tumor (GIST) remains unclear. LECS has potential oncology-related problems that may influence survival outcomes. Furthermore, the feasibility and safety of LECS have not yet been fully established. Patients and methods Patients who were intended to undergo LECS for gastric GIST from 2006 to 2020 were retrospectively selected. The indication for LECS was determined according to the guidelines. The completion of LECS, complications, and survival outcomes of the patients were analyzed. Results Two hundred fifty-nine patients were eligible in this study. According to intraoperative findings, 44 patients underwent local resection without luminal endoscopic procedures. Of the remaining 215 patients, 213 completely underwent LECS, which corresponds to a completion rate of 99.1 %. Six patients (2.8 %) had postoperative complications of Clavien-Dindo classification grade II or higher. Delayed gastric emptying was most commonly found in four patients (1.9 %). Old age ( P  = 0.0349), female sex ( P  = 0.0095), tumor located in the lesser curvature ( P  = 0.0015), and large tumor diameter ( P  = 0.0232) were significantly more common in patients with complications. The 3-year overall and disease-specific survival rates were 99 % and 100 %, respectively, in 215 patients who were intended to undergo LECS. Conclusions Despite several oncological concerns, LECS for gastric GIST is oncologically safe besides a feasible and safe procedure in the short-term.

Multiple myeloma with esophageal involvement: A rare case.

A 77-year-old man presented with a spinal cord tumor at the cervical 7/thoracic 1 level and pain and weakness in the right hand. Blood tests revealed anemia, renal dysfunction, and hyperproteinemia. Immunoelectrophoresis revealed the M-protein component of immunoglobulin G gamma globulin. Bone marrow aspirate contained an increased number of atypical plasma cells. He was diagnosed with symptomatic myeloma and treated with radiation therapy, chemotherapy, and extradural tumor resection. Upper gastrointestinal endoscopy, performed because of anemia progression, revealed a 5-mm submucosal tumor-like elevated lesion in the upper thoracic esophagus. On white light observation, the lesion appeared whitish with a central redness. Our patient was diagnosed with extramedullary multiple myeloma. Extramedullary lesions are rare in the gastrointestinal tract. To our knowledge, this case is the first of multiple myeloma with esophageal involvement.

Risk Factors for Non-Ampullary Duodenal Adenocarcinoma: A Systematic Review.

INTRODUCTION: An increase in the incidence of duodenal adenocarcinoma has been recently reported. However, little is known about the risk factors for duodenal adenocarcinoma, which are important for screening purposes. We, therefore, aimed to conduct a systematic review to identify risk factors for non-ampullary duodenal adenocarcinoma. METHODS: A medical literature search was performed using electronic databases, including PubMed, Cochrane Library, Japan Medical Abstracts Society, and Web of Science. Studies that assessed the association between dietary habits, lifestyle behaviors, comorbidities, and non-ampullary duodenal adenocarcinoma were extracted. The Newcastle-Ottawa Scale was used to assess the risk of bias in individual studies, and the Grading of Recommendations, Assessment, Development, and Evaluations approach was used to assess the quality of evidence across studies included in this review. RESULTS: Out of 1,244 screened articles, 10 were finally selected for qualitative synthesis. In the general population, no consistent risk factors were identified except for Helicobacter pylori positivity, which was considered a risk factor in 2 studies, but the quality of evidence was considered very low because of the high risk of bias. In patients with familial adenomatous polyposis (FAP), Spigelman stage IV at initial endoscopy was considered a consistent risk factor in 3 studies. CONCLUSIONS: There are currently limited data regarding risk factors for non-ampullary duodenal adenocarcinoma, and no conclusive risk factors were identified in the general population. However, in patients with FAP, Spigelman stage IV was identified as a consistent risk factor. Further studies are needed to improve diagnosis and support effective clinical management of this malignancy.

A novel diagnostic system for superficial nonampullary duodenal epithelial tumors sized ≤ 5 mm.

BACKGROUND: An association between specific endoscopic findings and high-grade dysplasia/carcinoma in superficial nonampullary duodenal epithelial tumors ≤ 5 mm in size has not been reported. We sought to identify the endoscopic findings associated with high-grade dysplasia/carcinoma in patients with superficial nonampullary duodenal epithelial tumors ≤ 5 mm. METHODS: We retrospectively assessed the data of 84 patients (88 lesions; low-grade dysplasia: n = 35, high-grade dysplasia/carcinoma: n = 53) with superficial nonampullary duodenal epithelial tumors who underwent initial treatment at a single center (from July 2009 to April 2021). All the patients had lesions sized ≤ 5 mm. We assumed that the endoscopic findings were independently associated with high-grade dysplasia/carcinoma and determined the accuracy, sensitivity, and specificity of a combination of independent factors for diagnosing high-grade dysplasia/carcinoma and low-grade dysplasia. RESULTS: Multivariate logistic regression of significant factors in the univariate analysis revealed that lesions with depressed morphology (odds ratio: 23.9, 95% confidence interval: 2.8-204.2; p = 0.0037) and a reddish color (odds ratio: 175.7, 95% confidence interval: 11.4-2697.1; p = 0.0002) were independently associated with high-grade dysplasia/carcinoma. McNemar's test revealed that combining the macroscopic type and color provided significantly higher sensitivity for diagnosing high-grade dysplasia/carcinoma than color alone (98.1%, 95% confidence interval: 90.1-99.7 vs. 71.7%, 95% confidence interval: 58.4-82.0; p = 0.0002). CONCLUSIONS: Reddish and depressed-type lesions before treatment were associated with high-grade dysplasia/carcinoma. Combining the macroscopic type and color can help detect high-grade dysplasia/carcinoma. These findings could help clinicians determine the best therapeutic strategy for patients with smaller (≤ 5 mm) superficial nonampullary duodenal epithelial tumors in clinical settings.

A Case of Liver Metastasis from Small Intestinal Gastrointestinal Stromal Tumor 25 Years after Surgery including Autopsy Findings.

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the digestive tract. Recurrences may occur even after radical resection; however, recurrence later than 10 years after surgery is rare. We report a case of GIST with recurrence of liver metastasis 25 years after surgery. A 56-year-old man complained of sudden epigastric pain and was transferred to the emergency department. He had undergone partial resection of the small intestine for leiomyosarcoma 25 years previously. Abdominal computed tomography showed multiple liver tumors with massive hemorrhage. Ultrasound-guided percutaneous biopsy was performed for the 15-mm hepatic tumor in segment 2. Pathological findings revealed proliferation of spindle-shaped atypical cells, and immunostaining for c-kit and CD34 was both positive; the patient was therefore diagnosed with GIST. He then underwent chemotherapy for 7 years but died of multiple organ failure due to GIST. Autopsy revealed GIST occupying the entire liver with peritoneal dissemination, and minute lung metastases that could not be identified by CT were also detected. This case is interesting in considering the recurrence of GIST, and we will report it together with the literature review.

Efficacy of endoscopic preventive procedures to reduce delayed adverse events after endoscopic resection of superficial nonampullary duodenal epithelial tumors: a meta-analysis of observational comparative trials.

BACKGROUND AND AIMS: Although various procedures have been used to prevent serious adverse events after endoscopic resection of the duodenum, their effectiveness has not been determined. In this study, we conducted a systematic review and meta-analysis to determine whether endoscopic preventive procedures reduce delayed adverse events. METHODS: Studies on endoscopic treatment for superficial nonampullary duodenal tumors were selected. We compared the following 2 groups: the closure group, which underwent mucosal sutures and coverage of mucosal defects after resection, and the unclosed group, which did not. The primary outcome was the rate of delayed adverse events, including perforation and bleeding. The pooled risk ratios (RRs) of all outcomes investigated, the 95% confidence intervals (CIs), and P values were calculated. RESULTS: A total of 438 patients from 4 studies were included in the meta-analysis. The pooled overall adverse event rates in the closure group and unclosed group were 3.6% and 21.1%, respectively. This rate was significantly lower in the closure group (RR, 0.19; 95% CI, 0.10-0.38; P < .01; I2 = 0%), and the rate of delayed bleeding was significantly lower in the closure group (RR, 0.14; 95% CI, 0.06-0.33; P < .01; I2 = 0%). Regarding delayed perforation, the RR in the closure group was 0.39 (95% CI, 0.12-1.32; P = .13; I2 = 0%). CONCLUSIONS: Preventive procedures significantly reduced the risk of delayed adverse events by more than 80%. After endoscopic resection of the duodenum, the implementation of preventive procedures, including mucosal sutures and coverage of mucosal defects, to delay adverse events is strongly recommended.

The incidence of non-ampullary duodenal cancer in Japan: The first analysis of a national cancer registry.

BACKGROUND AND AIM: Although duodenal cancer is rare, no epidemiological research on this disease has been conducted in Asian countries. We aimed to elucidate the incidence and clinical features of duodenal cancer in Japan using a large-scale national database. METHODS: Data of patients with primary duodenal cancer diagnosed from January 1, 2016, to December 31, 2016, were extracted from the Japanese national cancer registry. Excluding malignant neoplasm of the Vater's ampulla, we calculated the incidence among the population as a crude number of patients with duodenal cancer divided by the total Japanese population in 2016. We performed multivariate analyses using logistic regression models to identify risk factors for advanced cancer, defined as metastatic cancer or local invasion to adjacent organs. RESULTS: Data on 3005 patients were included. The incidence of duodenal cancer was 23.7 per 1 000 000 person-years. In total, 56.4% of cases were detected at the localized stage. In the localized cancer group, endoscopic resection was more frequently performed (48.0%), whereas in the advanced cancer group, surgery and chemotherapy were the major treatment options (39.3% and 41.5%, respectively). Multivariate analyses identified age ≥80 years (odds ratio [OR], 1.489; 95% confidence interval [CI], 1.113-1.992; P = 0.007), incidental detection (OR, 2.325; CI, 1.623-3.331; P < 0.0001), and precise examination for symptomatic patients (OR, 10.561; CI, 7.416-15.042; P < 0.0001) as independent risk factors for advanced cancer. CONCLUSIONS: Our study revealed the incidence of duodenal cancer in Japan. However, localized cancer was the major tumor stage at detection, resulting in a high rate of endoscopic resection.

Acceptability of endoscopic submucosal dissection for sessile serrated lesions: comparison with non-sessile serrated lesions.

Background and study aims Sessile serrated lesions (SSL) are major precursor lesions of serrated pathway cancers, and appropriate treatment may prevent interval colorectal cancer. Studies have reported the outcomes of endoscopic mucosal resection (EMR) for SSL; however, there are insufficient reports on endoscopic submucosal dissection (ESD). We examined the characteristics and outcomes of SSL and compared them to those of non-SSL in ESD. Patients and methods We reviewed 370 consecutive cases in 322 patients who underwent colorectal ESD between January 2016 and March 2020 at our hospital. There were 267 0-IIa lesions that were stratified into 41 SSL and 226 non-SSL (intramucosal cancer, adenoma) cases. We used propensity matching to adjust for the variances in the factors affecting treatment between the SSL and non-SSL groups. Results In the baseline cases, young women and proximal colon tumor location were significantly more common in the SSL group. There were no statistically significant differences between the SSL and non-SSL groups in terms of en bloc resection rate (97.6 % vs. 99.6 %; P  = 0.28), R0 resection rate (92.7 % vs. 93.4 %; P  = 0.74), perforation (0 % vs. 0.9 %; P  > 0.99), and postoperative bleeding (2.4 % vs. 1.8 %; P  = 0.56). Thirty-eight pairs were matched using propensity score, and the median dissection speed (12 vs. 7.7 cm 2 /h; P  = 0.0095) was significantly faster in the SSL than in the non-SSL group. Conclusions ESD for SSL was safely performed, and SSL was smoother to remove than non-SSL. ESD might be an acceptable endoscopic treatment option for SSL.

Clinicopathological features and risk factors for lymph node metastasis in early-stage non-ampullary duodenal adenocarcinoma.

BACKGROUND: Management strategies for primary non-ampullary duodenal adenocarcinoma (NADAC) in early stage are not well established given its low incidence. This study aimed to elucidate clinicopathological features of early NADAC, including risk for lymph nodal metastasis (LNM). METHODS: In total, 166 patients with early NADAC underwent initial treatment at our institution between 2006 and 2019, of whom 153 had intramucosal (M-) and 13 had submucosal (SM-) NADAC. These endoscopic and pathological features were retrospectively analyzed. Risk factors for LNM were evaluated in 46 early NADAC patients who underwent surgery with lymph node dissection. RESULTS: Compared with M-NADAC, SM-NADAC was significantly more frequently located at the proximal side of the papilla, with mixed elevated and depressed macroscopic type, histologically poorly differentiated tumor and lymphovascular invasion (LVI) (85% vs. 47%, P = 0.009; 54% vs. 5%, P < 0.001; 23% vs. 0%, P < 0.001; and 46% vs. 0%, P < 0.001, respectively). The frequency of LNM was significantly higher in SM-NADAC than in M-NADAC (5/12, 42% vs. 0/34, 0%; P < 0.001). In SM-NADAC, the frequency of LNM was higher in poorly differentiated than in well to moderately differentiated tumors (3/3, 100% vs. 2/9, 22%) and higher in tumors with LVI than in those without LVI (3/5, 60% vs. 2/7, 29%). Regarding invasion depth, 2 of 4 patients with SM invasion (400 ≤ × < 500 µm) showed LNM. However, in this study, no patients developed very shallow SM invasion (0 < × < 400 µm). CONCLUSIONS: SM-NADAC showed high LNM risk. Surgical treatment with regional lymph node dissection is recommended as a treatment strategy for SM-NADAC.

Innovative therapeutic endoscopy in the upper gastrointestinal tract: Review of Japan Gastroenterological Endoscopic Society Core Sessions.

Workshops on "Innovative Therapeutic Endoscopy" for upper gastrointestinal tract diseases were held four times as the Japan Gastroenterological Endoscopic Society (JGES) Core Sessions at the 93rd to 96th Biannual Meetings of the JGES. A total of 48 research presentations (including two invited lectures) were reported, and various discussions were held on these topics. When the research presentations were categorized according to the therapeutic procedure, endoscopic submucosal dissection (ESD) was the most frequent with 28 presentations (58.3%), followed by laparoscopy endoscopy cooperative surgery (LECS) with six presentations (12.5%). When the research presentations were classified by the target organ of the therapeutic procedures, the duodenum was the most frequent with 26 presentations (54.1%), followed by the stomach with 13 presentations (27.1%). The most important issue was the establishment of a safe and reliable endoscopic resection method for duodenal lesions. Issues related to gastric ESD were establishing an efficient traction method and a method to prevent post-ESD bleeding in high-risk patients. Other important issues were establishment of an efficient traction method and methods of preventing delayed bleeding in high-risk patients who undergo gastric ESD, expansion of indications for minimally invasive treatment using LECS for gastric cancer, the development of endoscopic full-thickness resection (EFTR) for gastric submucosal tumors (SMTs), and improvement of per-oral endoscopic myotomy (POEM) for esophageal achalasia and per-oral endoscopic tumor resection (POET) for esophageal SMTs. Through the JGES Core Sessions, it is expected that the minimally invasive treatments using endoscopes developed in Japan will be further advanced.

Undifferentiated-type predominant mixed-type early gastric cancer is a significant risk factor for requiring additional surgeries after endoscopic submucosal dissection.

We aimed to clarify the differences in therapeutic outcomes of patients with pure undifferentiated-type and mixed undifferentiated-type cancers who underwent endoscopic submucosal dissection (ESD), and whether pre-treatment diagnosis of mixed undifferentiated-type cancer is associated with requiring additional surgery after ESD. Patients subjected to ESD as initial treatment between May 2005 and March 2017 were enrolled. There were 277 undifferentiated-type cancers (265 patients). Histologically, 258 lesions were pure-type and 19 were mixed-type. We compared therapeutic outcomes and pre-treatment factors (tumour diameter, tumour depth, ulcerative findings, tumour location, and the macroscopic, and histological type of the biopsy specimen) between pure-type and mixed-type lesions, and between cases not requiring additional surgeries and cases requiring additional surgeries. Tumour diameter >20 mm, submucosal invasion, and the presence of ulcerative findings made pre-treatment diagnosis more difficult for mixed-type than for pure-type lesions. In cases requiring additional surgery, pre-treatment diagnosis of mixed-type lesions was significantly more likely than pre-treatment diagnosis of pure-type lesions. For mixed-type lesions, pre-treatment histological diagnosis and careful consideration are necessary to determine indications for ESD to avoid additional surgery after ESD.

Efficacy and suitable indication of colorectal endoscopic submucosal dissection using a balloon-assisted endoscope.

BACKGROUND AND AIM: Cases of colorectal endoscopic submucosal dissection (ESD) with poor maneuverability are often encountered. We aimed to evaluate the efficacy of balloon-assisted endoscopy (BAE) for such cases. METHODS: We confirmed maneuverability preoperatively in 400 consecutive cases of colorectal ESD performed at a single center from April 2011 to April 2018. A total of 83 deep colon cases judged as having poor maneuverability were retrospectively reviewed; 54 cases underwent BAE with a single balloon endoscope (group B), and 29 cases underwent conventional procedures without BAE (group C). Tumor size, procedure duration, dissection speed, en bloc resection rate, histology, and associated complications were compared between groups. RESULTS: The mean tumor size, tumor invasiveness, fibrosis, and complications did not differ between groups. Although the en bloc resection rate did not differ (both 98%), the groups significantly differed with regard to the R0 resection rate (B: 96%; C: 83%; P = 0.048). Overall, the procedure duration (B: 51 min; C: 70 min; P = 0.17) and dissection speed (B: 19.4 mm2/min; C: 17.4 mm2/min; P = 0.13) were not significantly different between groups. However, the dissection speed for lesions in the cecum/ascending colon was significantly faster in group B than in group C (B: 22.3 mm2/min; C: 11.3 mm2/min; P = 0.037). CONCLUSIONS: In cases of colorectal ESD with poor maneuverability, the use of BAE contributed to an improvement in the R0 resection rate. In addition, BAE contributed to a quicker dissection speed for lesions located in the cecum/ascending colon.

Additive Effect of Magnifying Endoscopy with Narrow-Band Imaging for Diagnosing Mixed-Type Early Gastric Cancers.

BACKGROUND: Pretreatment biopsy may not correctly diagnose mixed-type early gastric cancers. Despite reports on the usefulness of magnifying endoscopy with narrow-band imaging in diagnosing early gastric cancers, no reports exist on differences in magnifying endoscopy with narrow-band imaging findings between differentiated-type-predominant mixed-type and undifferentiated-type-predominant mixed-type early gastric cancers. AIM: This study aimed to clarify differences in magnifying endoscopy with narrow-band imaging findings and investigate the additive effect of combining magnifying endoscopy with narrow-band imaging and biopsy findings for pretreatment histological-type diagnosis. METHODS: Patients undergoing endoscopic submucosal dissection as initial treatment between April 2005 and March 2017 participated in this retrospective study. There were 156 differentiated-type-predominant mixed-type and 36 undifferentiated-type-predominant mixed-type lesions. We extracted the most significant magnifying endoscopy with narrow-band imaging findings of differentiated-type-predominant mixed-type and undifferentiated-type-predominant mixed-type lesions using multivariate analysis and compared the accuracy, sensitivity, and specificity between pretreatment biopsy alone and a combination of biopsy and magnifying endoscopy with narrow-band imaging findings. RESULTS: Significant magnifying endoscopy with narrow-band imaging findings was fine network pattern in differentiated-type-predominant and corkscrew pattern in undifferentiated-type-predominant mixed-type lesions. Accuracy, sensitivity, and specificity were significantly higher with combined biopsy and magnifying endoscopy with narrow-band imaging findings than with pretreatment biopsy alone. CONCLUSIONS: The study results demonstrated the additive effect of magnifying endoscopy with narrow-band imaging with biopsy for diagnosing mixed-type early gastric cancers. This study may be beneficial in routine practice because it indicates a possibility of reducing additional surgery after endoscopic submucosal resection because of incorrect diagnosis of histological type.

Pretreatment diagnosis factors associated with overtreatment with surgery in patients with differentiated-type early gastric cancer.

This study aimed to clarify the pretreatment factors associated with overtreatment with surgery in patients with differentiated-type early gastric cancer. This single-centre, retrospective study included 781 patients with differentiated-type early gastric cancer treated by surgical resection between April 2005 and May 2017. Postoperative pathological results were used to divide patients into the accurate surgical indication group and overtreatment with surgery group; the groups were compared with respect to accurate diagnosis and misdiagnosis based on tumour diameter (≤30 mm or >30 mm), diagnosis of depth, diagnosis of ulcerative findings, and diagnosis of main histology. There were 224 patients in the overtreatment with surgery group. Multivariate analysis revealed significant differences in misdiagnosis of tumour diameter, misdiagnosis of depth, misdiagnosis of ulcerative findings, and misdiagnosis of main histology between the accurate surgical indication group and overtreatment with surgery group. Significant factors for pretreatment misdiagnosis leading to overtreatment in differentiated-type early gastric cancer were tumour diameter, depth, and main histology. It may be acceptable to perform endoscopic resection for patients with pretreatment tumour diameter ≤30 mm, mucosal invasion of pretreatment depth, and undifferentiated-type cancers containing differentiated-type components of pretreatment histology because this reduces overtreatment with surgery.