Yorimasa Yamamoto

Long-term outcomes of endoscopic submucosal dissection for undifferentiated-type early gastric cancer.

BACKGROUND AND STUDY AIM Endoscopic submucosal dissection (ESD) of undifferentiated-type early gastric cancer (UD-EGC) is technically feasible; however, the long-term clinical outcomes of the procedure have not yet been fully investigated. The aim of our study was to elucidate long-term outcomes of ESD for UD-EGC. PATIENTS AND METHODS Between September 2003 and October 2009, a total of 153 patients were diagnosed endoscopically as having UD-EGC fulfilling the expanded criteria for ESD. After informed consent was obtained, 101 patients were selected to undergo ESD and 52 to undergo surgical operation. We assessed the clinical outcomes of ESD in 101 consecutive patients with 103 UD-EGC lesions who were undergoing ESD for the first time. The overall mortality and disease-free survival rates after ESD were evaluated as the long-term outcomes. RESULTS The rates of en bloc and curative resection were 99.0% (102/103) and 82.5% (85/103), respectively. We encountered one patient with nodal metastasis detected by computed tomography before diagnostic ESD, although curative resection of the primary lesion was achieved based on routine histological examination. Among the 78 patients without a past history of malignancy within the previous 5 years in whom curative resection of the primary lesion was achieved, no cases of local recurrence or distant metastasis were observed during follow-up; however, 1 synchronous and 2 metachronous lesions were detected in 2 patients (2.6%) after primary ESD. Thus, estimated over a median follow-up period of 40.0 months (range 19-92 months) and 36.0 months (range 9-92 months), the 3-and 5-year overall mortality rates were 1.9% and 3.9%, respectively, and the 3-and 5-year overall disease-free survival rates were both 96.7%. CONCLUSIONS Although our single-center retrospective study may be considered to be only preliminary, our data indicate that ESD for UD-EGC may yield good long-term outcomes.

THERAPEUTIC OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION OF UNDIFFERENTIATED-TYPE INTRAMUCOSAL GASTRIC CANCER WITHOUT ULCERATION AND PREOPERATIVELY DIAGNOSED AS 20 MILLIMETRES OR LESS IN DIAMETER

Aim:  The aim of the present study was to examine therapeutic outcomes of endoscopic submucosal dissection (ESD) of undifferentiated‐type intramucosal gastric cancer and the problems of diagnosis.

Sporadic nonampullary duodenal adenoma in the natural history of duodenal cancer: a study of follow-up surveillance.

OBJECTIVES:Although sporadic nonampullary duodenal adenoma (SNDA) is regarded as a precancerous lesion, its natural course is uncertain. The aim of this study was to evaluate the risk of development of adenocarcinoma in SNDA lesions initially diagnosed as showing low-grade dysplasia (LGD; category 3) or high-grade dysplasia (HGD; category 4.1).METHODS:We analyzed 68 SNDAs, diagnosed based on initial and subsequent biopsies, in 66 consecutive patients. Of these, 46 (43 LGD lesions, 3 HGD lesions) were followed up for ≥6 months without treatment (mean 27.7±16.9 months; range 6–72 months), including 8 lesions that were eventually resected during follow-up. Sixteen lesions (eight LGD lesions, eight HGD lesions) were resected immediately, either endoscopically or surgically, and six lesions were excluded because of a short follow-up (<6 months). The histopathological diagnoses and macroscopic changes were evaluated.RESULTS:Among the 43 LGD lesions followed up for ≥6 months, 34 (79.1%) showed no histopathological changes during follow-up, whereas the remaining 9 (20.9%) showed progression to HGD, including 2 (4.7%) that progressed eventually to noninvasive carcinoma (category 4.2). Macroscopically, 76.7% (33 of 43) of the LGD lesions showed no notable changes in size, 16.3% (7 of 43) became undetectable, 4.7% (2 of 43) reduced in size, and 2.3% (1 of 43) became larger in size. In contrast, all the three HGD lesions that were followed up for ≥6 months remained unchanged histologically, based on biopsy, and showed no notable macroscopic changes, although one of these HGD lesions resected endoscopically revealed evidence of noninvasive carcinoma. Although we diagnosed all lesions as HGD from biopsy samples, a high percentage of cancers (54.5%, 6 of 11) were diagnosed from resected specimens. A multivariate analysis identified HGD diagnosed at first biopsy and a lesion diameter of ≥20 mm as being significantly predictive of progression to adenocarcinoma.CONCLUSIONS:LGD lesions show a low risk of progression to adenocarcinoma, but some risk of progression to HGD, which warrants careful follow-up biopsy. However, HGD lesions and large SNDAs ≥20 mm in diameter show a high risk of progression to adenocarcinoma. Therefore, they should be treated immediately.

Multi‐center survey regarding the management of anticoagulation and antiplatelet therapy for endoscopic procedures in Japan

Background:  A guideline on the management of anticoagulation and antiplatelet therapy for endoscopic procedures has been established from Japan Gastroenterological Endoscopy Society in 2005. However, it is unknown whether consensus on the management of these conditions is obtained among endoscopists in daily practice owing to the guideline.

Endoscopic diagnosis of superficial non‐ampullary duodenal epithelial tumors in Japan: Multicenter case series

To verify the current status in Japan on endoscopic diagnosis of superficial non‐ampullary duodenal epithelial tumors (SNADET) by a multicenter case series through a questionnaire survey.

Diagnosis of undifferentiated type early gastric cancers by magnification endoscopy with narrow-band imaging.

Background and Aims:  The diagnostic use of magnification endoscopy with narrow‐band imaging (ME‐NBI) to assess histopathologically undifferentiated‐type early gastric cancers (UD‐type EGCs) is not well elucidated. The purpose of this study was to examine the comparative relationship between ME‐NBI images and histopathological findings in UD‐type EGCs.

Laparoscopic endoscopic cooperative surgery.

Laparoscopic and endoscopic cooperative surgery (LECS) is a newly developed concept for tumor dissection of the gastrointestinal tract that was first investigated for local resection of gastric gastrointestinal stromal tumors (GIST). The first reported version of LECS for GIST has been named ‘classical LECS’ to distinguish it from other modified LECS procedures, such as inverted LECS, a combination of laparoscopic and endoscopic approaches to neoplasia with a non‐exposure technique (CLEAN‐NET), and non‐exposed endoscopic wall‐inversion surgery (NEWS). These modified LECS procedures were developed for dissection of malignant tumors which may seed tumor cells into the abdominal cavity. While these LECS‐related procedures might prevent tumor seeding, their application is limited by several factors, such as tumor size, location and technical difficulty. Currently, classical LECS is a safe and useful procedure for gastric submucosal tumors without mucosal defects, independent of tumor location, such as proximity to the esophagogastric junction or pyloric ring. For future applications of LECS‐related procedures for other malignant diseases with mucosal lesions such as GIST with mucosal defects and gastric cancer, some improvements in the techniques are needed.

Therapeutic outcomes of endoscopic resection for superficial non‐ampullary duodenal tumor

Endoscopic resection (ER) is widely used as a minimally invasive therapy to remove superficial non‐ampullary duodenal tumor (SNADT). However, the indication criteria have not yet been clearly determined. At our institute, ER is done only for SNADT measuring ≤20 mm. We report our findings on the therapeutic outcomes of ER of SNADT.

HOW TO TEACH AND LEARN ENDOSCOPIC SUBMUCOSAL DISSECTION FOR UPPER GASTROINTESTINAL NEOPLASM IN JAPAN

Background:  Endoscopic submucosal dissection (ESD) is an innovative and promising procedure. However, ESD experience is mostly limited to Japan and a few countries in Asia. An appropriate training system should be proposed from Japan to promote a permeation of ESD technique. We conducted questionnaire survey to representative Japanese experts to reveal their training method of ESD for upper gastrointestinal neoplasm

CURRENT STATUS OF TRAINING FOR ENDOSCOPIC SUBMUCOSAL DISSECTION FOR GASTRIC EPITHELIAL NEOPLASM AT CANCER INSTITUTE HOSPITAL, JAPANESE FOUNDATION FOR CANCER RESEARCH, A FAMOUS JAPANESE HOSPITAL

Aim:  Endoscopic submucosal dissection (ESD) is relatively difficult compared with endoscopic mucosal resection (EMR), thus, proper training is essential for the safe performance of the procedure. The aim of this study is to clarify the current status of training for ESD for gastric epithelial neoplasm by following the performance of 13 preceptees.