Tsuneo Oyama

Endoscopic submucosal dissection of early esophageal cancer.

In Japan, the majority of esophageal cancers are squamous cell carcinomas. Because no lymph node metastasis was reported in squamous cell carcinomas limited to the intraepithelial layer (m1) or proper mucosal layer (m2), the Japanese Esophageal Association recommended endoscopic mucosal resection (EMR) as the treatment of choice for these cancers. However, these lesions often spread laterally, exceeding the limits of en bloc resectability with conventional EMR methods such as the EMR cap method. The lesions resected in piece-meal manner with conventional EMR methods are prone to recur locally. Therefore, we developed a method of mucosal resection with a hook-knife that enables endoscopic submucosal dissection safely and achieves a high rate of en bloc resection for larger lesions. The median size of the resected specimen and cancer by our method was 32 mm (range, 8-76 mm) and 28 mm (range, 4-64 mm), respectively. The en bloc resection rate was 95% (95 of 102) and the local recurrence rate was 0% (0 of 102). This procedure was safe, with only 6 cases (6%) of mediastinal emphysema, which improved with conservative treatment. Endoscopic submucosal dissection with the hook knife is a method of endoluminal surgery enabling large en bloc resections without increased surgical risks.

A multicenter retrospective study of endoscopic resection for early gastric cancer.

BackgroundThe reported outcomes of endoscopic resection (ER) for early gastric cancer (EGC) remain limited to several single-institution studies.MethodsA multicenter retrospective study was conducted at 11 Japanese institutions concerning their results for ER, including conventional endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD).ResultsA total of 714 EGCs (EMR, 411; ESD, 303) in 655 consecutive patients were treated from January to December 2001. Technically, 511 of the 714 (71.6%) lesions were resected in one piece. The rate of one-piece resection with ESD (92.7%; 281/303) was significantly higher compared with that for EMR (56.0%; 230/411). Histologically, curative resection was found in 474 (66.3%) lesions. The rate of curative resection with ESD (73.6%; 223/303) was significantly higher compared with that for EMR (61.1%; 251/411). Blood transfusion because of bleeding was required in only 1 patient (0.1%) with EMR of 714 lesions. Perforation was found in 16 (2.2%). The incidence of perforation with ESD (3.6%; 11/303) was significantly higher than that with EMR (1.2%; 5/411). All complications were managed endoscopically, and there was no procedure-related mortality. The median follow-up period was 3.2 years (range, 0.5–5.0 years). In total, the 3-year cumulative residual-free/recurrence-free rate and the 3-year overall survival rate were 94.4% and 99.2%, respectively. The 3-year cumulative residual-free/recurrence-free rate in the ESD group (97.6%) was significantly higher than that in the EMR group (92.5%).ConclusionER leads to an excellent 3-year survival in clinical practice and could be a possible standard treatment for EGC. ESD has the advantage of achieving one-piece resection and reducing local residual or recurrent tumor.

Comprehensive Registry of Esophageal Cancer in Japan, 2009

These data were first made available on January 2016, as the Comprehensive Registry of Esophageal Cancer in Japan, 2009. Not all the tables and figures are reprinted here. The authors were members of the Registration Committee for Esophageal Cancer, the Japan Esophageal Society, and made great contributions to the preparation of this material.

Guidelines for Diagnosis and Treatment of Carcinoma of the Esophagus April 2012 edited by the Japan Esophageal Society

Purpose These guidelines are intended for doctors who are engaged in the diagnosis and treatment of esophageal carcinoma, for the following purposes: (1) to present the standard practice for the diagnosis and treatment of esophageal carcinoma with a high regard for the principles of evidence-based medicine (EBM); (2) to improve the safety and results of treatment, thereby reducing the difference in treatment results among different institutions; (3) to reduce unnecessary costs and efforts; (4) help enable people to undergo treatment without anxiety. These guidelines provide only guidance on the indications for treatment and do not restrict or prohibit the use of any treatment deviating from those described herein.

LEARNING CURVE FOR ENDOSCOPIC SUBMUCOSAL DISSECTION OF LARGE COLORECTAL TUMORS

Background and Aim:  No studies have previously described the learning curve for colonic endoscopic submucosal dissection (ESD). The aim of the present study was to describe the learning curve for ESD of large colorectal tumors based on a single colonoscopists experience.

Experimental endoscopic submucosal dissection training in a porcine model: Learning experience of skilled western endoscopists

Background:  Endoscopic submucosal dissection (ESD) demands a new level of endoscopic skill in Europe. A 2‐day workshop was set up for trainees to carry out five ESD each in order to obtain the skill level required to perform ESD in the stomach or rectum. This study describes: (i) the workshop setup; (ii) the participants performance; and (iii) the training effect on post‐workshop clinical ESD performance.

Preliminary results of multicenter questionnaire study on long-term outcomes of curative endoscopic submucosal dissection for early gastric cancer.

There are a number of published reports on long‐term outcomes of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC), but most reports are from single centers with median follow‐up periods shorter than 5 years. This questionnaire study investigated long‐term outcomes of curative ESD for EGC at six Japanese institutions with follow‐up rates of at least 90% over a minimum 5‐year period.

Comprehensive Registry of Esophageal Cancer in Japan, 2006

We deeply appreciate the great contributions of many physicians in the registry of esophageal cancer cases. The Comprehensive Registry of Esophageal Cancer in Japan, 2006, was published here, despite some delay. The registry complies with the Act for the Protection of Personal Information. The encryption with a HASH function is used for ‘‘anonymity in an unlinkable fashion’’. We briefly summarized the Comprehensive Registry of Esophageal Cancer in Japan, 2006. Japanese Classification of Esophageal Cancer 9th and UICC TNM Classification 6th were used for cancer staging according to the subjected year. A total of 4994 cases were registered from 239 institutions in Japan. Tumor locations were cervical: 4.2 %, upper thoracic: 13.4 %, middle thoracic: 48.7 %, lower thoracic: 26.0 % and EG junction: 6.7 %. Superficial carcinomas (Tis, T1a, T1b) were 35.9 %. As for the histologic type of biopsy specimens, squamous cell carcinoma and adenocarcinoma accounted for 90.8 and 3.9 %, respectively. Regarding clinical results, the 5-year survival rates of patients treated using endoscopic mucosal resection, concurrent chemoradiotherapy, radiotherapy alone, chemotherapy alone, or esophagectomy were 84.5, 25.8, 22.0, 3.0, and 48.0 %, respectively. Esophagectomy was performed in 2545 cases. Concerning the approach used for esophagectomy, 15.4 % of the cases were treated These data were first made available on July 1, 2013, as the Comprehensive Registry of Esophageal Cancer in Japan, 2006. Not all the pages are reprinted here; however, the original table and figure numbers have been maintained.

Comprehensive Registry of Esophageal Cancer in Japan, 2010

These data were first made available on January 2017, as the Comprehensive Registry of Esophageal Cancer in Japan, 2010. Not all the pages are reprinted here.

Local recurrence and surveillance after endoscopic resection of large colorectal tumors.

Local recurrence rates after endoscopic piecemeal mucosal resection (EPMR) typically range from 10 to 23%. In our previous study, the local recurrence rate after a piecemeal resection was significantly higher than that after an en bloc resection, irrespective of tumor size or macroscopic features. To reduce local recurrence after an EPMR, it is important to carefully note the circumferences of the edge and base of the ulcer. Recently, endoscopic submucosal dissection (ESD) was developed and recognized for its effectiveness in large, complete, en bloc resections and precise pathological assessments. ESD also showed lower local recurrence rates, ranging from 0 to 3% in previous, retrospective studies. However, ESD showed a higher perforation rate and longer procedure times; thus, it is necessary to improve ESD. An appropriate surveillance interval after EPMR was still controversial, and recommendations of some guidelines ranged from 2 to 9 months. In order to determine the appropriate interval, a randomized controlled study is necessary.