Laparoscopic and endoscopic cooperative surgery (LECS), which provides safe, secure, and optimally-designed full-thickness resection, has been covered by insurance in Japan since 2014, and has been accepted as a less-invasive local resection technique mainly for gastric submucosal tumors both domestically and internationally. After introducing an exposure technique (classical LECS), non-exposure techniques, e.g., combination of laparoscopic and endoscopic approaches to neoplasia with non-exposure technique (CLEAN-NET) and non-exposed endoscopic wall-inversion surgery (NEWS), have been developed, which enable us to choose the optimal method according to characteristics of the target lesions. Currently, leading hospitals are trying to expand the indications for LECS to gastric cancers and tumors in other organs, and further to fuse it with sentinel node navigation surgery. Expansion of the indications for LECS is expected in the future.

Background: There have been several studies on risk factors for lymph node metastasis in patients with submucosal invasive colorectal cancer, and the indication of additional surgical operation after endoscopic resection is controversial. Some case reports showed that the prognosis of submucosal invasive colorectal cancer may be worsened by initial endoscopic resection prior to subsequent surgical operation.

Methods: A total of 118 patients with submucosal invasive colorectal cancer who underwent colectomy with lymphadenectomy at our hospital, were analyzed. We investigated the risk factors for lymph node metastasis, and relapse-free and overall survival. We evaluated the influence of endoscopic resection of submucosal invasive colorectal cancer prior to surgical operation.

Results: Thirty-seven (31.4%) of the 118 patients underwent endoscopic resection prior to colectomy with lymphadenectomy. Lymphatic invasion was the only risk factor for lymph node metastasis. When lymphatic invasion was negative and depth of submucosal invasion was less than 3,500μm, there was no lymph node metastasis. There were no significant differences between the two groups who did or did not undergo endoscopic resection prior to surgical operation in relapse-free and overall survival.

Conclusion: Endoscopic resection of submucosal invasive colorectal cancer prior to surgical operation may not worsen the prognosis. Endoscopic resection with R0 resection prior to surgery may be applicable to submucosal invasive colorectal cancers when precise evaluation of depth of submucosal invasion is difficult.

A healthy 13-year-old male with fever, postprandial chest pain and anorexia was diagnosed with bronchitis by his family doctor and received antibiotic therapy for seven days. The symptoms did not improve, and he was referred to our hospital. Endoscopy revealed a small erosion and a sharply demarcated, punched-out, circular ulcer in the middle esophagus, and many longitudinal confluent ulcers in the distal esophagus. Histological examination of the esophageal biopsy specimens showed inflammation and giant cells with nuclear enlargement and ground-glass nuclei in epithelial cells. Immunohistochemical staining for herpes simplex virus (HSV) antibody was positive. Serologically, he was positive for anti-HSV immunoglobulin (Ig) M and negative for anti-HSV IgG at the time of the first visit. However, anti-HSV-IgG showed seroconversion during the recovery period. We diagnosed herpes esophagitis caused by primary HSV infection in this healthy child. Herpes esophagitis by primary HSV infection is rare, because it is considered that herpes esophagitis is usually caused by recurrent HSV infection in an immunocompromised or debilitated host. After administration of valacyclovir for 7 days, his symptoms and endoscopic findings promptly improved.

A 79-year-old woman underwent endoscopic examination in 2008 and esophagogastroduodenoscopy showed a polypoid lesion in the gastric fornix that was similar in appearance to a hyperplastic polyp. Approximately five years later, the polypoid lesion had slightly enlarged and was now partially surrounded by a depressed lesion. Magnifying narrow band imaging indicated irregular microvascular and absent microsurface patterns within a demarcation line. We diagnosed the patient with early gastric adenocarcinoma, type 0-Ⅱa＋Ⅱc. Endoscopic submucosal dissection was performed. Pathological examination of the resected specimen showed a very well-differentiated tubular adenocarcinoma with differentiation towards the pyloric gland phenotype. Immunohistochemical examination showed positivity for MUC6 and lysozyme, but not pepsinogen-Ⅰ. Therefore, the polypoid lesion was diagnosed as an intramucosal gastric adenocarcinoma of the pyloric mucosa type exhibiting a gastric phenotype. This is the first case of a gastric adenocarcinoma of pyloric mucosa type which was intramucosal carcinoma.

A 72-year-old man was being followed up after endoscopic submucosal dissection of esophageal cancer. An 8-mm, mucosal, elevated lesion was noted in the posterior wall of the gastric fornix, and was identified as Group 1 on biopsy. Examination six months later showed that the lesion had grown to 15 mm, with a morphology resembling that of a submucosal tumor. Gastric cancer (pap) was diagnosed from biopsy. Endoscopic ultrasound (EUS) revealed hyperechoic spots in the submucosa, and submucosal invasion of gastric cancer was suspected. Given the possibility of reactive changes and the patientʼs own wishes, endoscopic submucosal dissection was performed. Histopathological examination revealed a transitional appearance from normal epithelial cells to tumor cells inside an ectopic gastric gland together with calcifications within the tumor. This was considered to represent a calcified cancer originating from an ectopic gastric gland. We report herein a case of gastric cancer originating from an ectopic gastric gland with submucosal tumor-like morphology and characteristic appearance on EUS.

The incidence of complications related to endoscopic retrograde cholangiopancreatography (ERCP) is relatively high compared with that related to other endoscopic procedures and the complications can worsen the patientʼs condition. In particular, duodenal perforation (DP) is life-threatening and usually requires emergency surgical interventions. Here, we demonstrate a successfully treated case of spontaneous DP during ERCP under endoscopic closure using the clipping technique. A 78-year-old woman was diagnosed with acute obstructive cholangitis due to choledocholithiasis. ERCP followed by endoscopic sphincterotomy (EST) and balloon choledocholithotomy was performed and succeeded in stone removal. However, while stretching the scope, the inferior duodenal angulus was injured with the scope head. Fat tissues, which seemed to be retroperitoneal fat, were observed through the injured mucosa, suggesting that ERCP-related DP occurred. The patient developed no symptoms and her general condition was stable. Although the hole was as large as 15 mm, no gas was detected in the intra-abdominal cavity under fluoroscopy. We tried to close the mucosal defect under endoscopy using the clipping technique. A total of seven clips were applied on the defect from both edges, shrinking the hole clip by clip. After complete mucosal closure, contrast enhance reagent was applied and only a small amount was retained in the retroperitoneal cavity. Intensive follow-up with antibiotic therapy was continued and her clinical course was uneventful. Although the indication for endoscopic closure of DP depends on the patientʼs condition, technical skill of the endoscopist and backup of surgeons, this endoscopic procedure is less invasive than surgical intervention and worth considering. We report our case with a literature review.

A 79-year-old male with severe anemia was referred to our hospital for a suspected tumor in the small intestine. Contrast computed tomography (CT) and positron emission tomography (PET)-CT showed a tumor lesion in the jejunum. Oral single-balloon enteroscopy and small bowel capsule endoscopy revealed a Type 2 lesion in the jejunum and a Type 0-Ⅱc lesion in the third portion of the duodenum. Histopathological examination of biopsy specimens showed that both lesions were adenocarcinomas. Here, we report a very rare case of simultaneous multiple primary small bowel cancers in a patient without known risk factors such as inflammatory bowel disease or hereditary condition (e.g., familial adenomatous polyposis, Lynch syndrome, Peutz-Jeghers syndrome).

Radiation therapy is increasingly the first choice of treatment for pelvic malignancies such as prostate cancer and uterine cancer. However, radiation colitis is an acute or chronic side effect in the small and large bowels and includes hemorrhagic sigmoid proctitis, ulcer formation, stenosis and fistula. Bloody stool is the most frequent symptom of radiation proctitis (RP). We propose the following classification of RP in order to systematically perform treatment with argon plasma coagulation (APC): Type A, localized telangiectasia; Type B, diffuse telangiectasia; Type C, shallow ulcer or erosion with diffuse telangiectasia, major indication is active bleeding; and Type D, deep ulcer and remarkably fragile mucosa. Four points on the technique of APC treatment are as follows: Ⅰ, Spotting technique; Ⅱ, rinsing well with water to be able to recognize target vessels; Ⅲ, inverting the endoscope to look up the anal canal with a slim scope; Ⅳ, multi-session strategy. Starting from recognizing the classification according to the condition being treated, a long-term hemostatic effect can be obtained based on the treatment strategy, technique of the coagulation method, and judgment of its effect.

Hot AXIOS^TM (Boston Scientific, Marlborough, MA) as a lumen-apposing metal stent (LAMS) can be used when performing endoscopic ultrasound (EUS)-guided transluminal drainage of walled-off necrosis (WON) and pancreatic pseudocysts, and the endoscopic treatment strategy has changed significantly. The larger bore diameter of LAMS compared with that of conventional plastic and metal stents makes it possible to obtain greater drainage volume, and endoscopists can easily perform necrosectomy using LAMS in which the endoscope is directly inserted into the cavity of WON and used to remove necrotic material. If the WON is not so large and the WON lumen is mostly filled with fluid, plastic stent placement can improve WON without necrosectomy. On the other hand, LAMS should be used if there is a wide spread of necrotic tissue and if necrosectomy is expected to be performed. Endoscopic treatment of WON is associated with fatal adverse events, and therefore radiologists and surgeons should be prepared with back-up plans.

Objectives: A Japanese multicenter prospective cohort study examining endoscopic resection (ER) for early gastric cancer (EGC) has been conducted using a Web registry developed to determine the short-term and long-term outcomes based on absolute and expanded indications. We hereby present the short-term outcomes of this study.

Methods: All consecutive patients with EGC or suspected EGC undergoing ER at 41 participating institutions between July 2010 and June 2012 were enrolled and prospectively registered into the Web registry. The baseline characteristics were entered before ER, and the short-term outcomes were collected at 6 months following ER.

Results: Nine thousand six hundred and sixteen patients with 10,821 lesions underwent ER (endoscopic submucosal dissection [ESD]: 99.4%). The median procedure time was 76 min, and R0 resections were achieved for 91.6% of the lesions. Postoperative bleeding and intraoperative perforation occurred in 4.4% and 2.3% of the patients, respectively. Significant independent factors correlated with a longer procedure time (120 min or longer) were as follows: tumor size ＞20 mm, upper-third location, middle-third location, local recurrent lesion, ulcer findings, gastric tube, male gender, and submucosa. Histopathologically, 10,031 lesions were identified as common-type gastric cancers. The median tumor size was 15 mm. Noncurative resections were diagnosed for 18.3% of the lesions. Additional surgery was performed for 48.6% (824 lesions) of the 1,695 noncurative ER lesions with a possible risk of lymph node (LN) metastasis. Among them, 64 (7.8%) exhibited LN metastasis.

Conclusions: This multicenter prospective study showed favorable short-term outcomes for gastric ESD.

Objective: Recommendations vary on postpolypectomy surveillance, and no consensus has been reached even regarding the necessity of risk stratification based on polyp characteristics for surveillance. We examined an optimal postpolypectomy surveillance program by performing a cost-effectiveness analysis.

Methods: We performed a Markov model analysis using parameters based on Japanese data and evaluated four postpolypectomy surveillance programs with respect to their effectiveness in terms of quality-adjusted life-years (QALYs), cost-effectiveness and required number of colonoscopies. Two were non-risk-stratified programs with 1-year (program 1) and 3- year (program 2) postpolypectomy surveillance colonoscopy, and the other two were risk-stratified programs. In program 3, surveillance colonoscopy was performed 3, 10 and 10 years after resection of advanced adenomas, low-risk adenomatous polyps, and no polyps, respectively. In program 4, those intervals were shortened to 1, 3 and 5 years, respectively.

Results: Risk-stratified programs (3 and 4) yielded higher QALYs with lower costs than non-risk-stratified programs (1 and 2). Program 4 yielded higher QALYs (23.046) and lower required cost (107,717 JPY) than program 3. The required number of colonoscopies for program 4 was 1.2, 1.5 and 1.6 times that for programs 1, 2 and 3, respectively. A probabilistic sensitivity analysis showed that the probability of program 4 being chosen as the most cost-effective was highest.

Conclusions: After polypectomy, risk-stratified colonoscopy surveillance based on the polyp characteristics should be considered. A risk-stratified program with relatively short examination intervals could be effective and cost-effective in Japan, although further investigation and consideration of colonoscopy capacity are required.