Hisashi Doyama

Magnifying narrowband imaging is more accurate than conventional white-light imaging in diagnosis of gastric mucosal cancer.

BACKGROUND & AIMS It is difficult to accurately diagnose patients with depressed gastric mucosal cancer based on conventional white-light imaging (C-WLI) endoscopy. We compared the real-time diagnostic yield of C-WLI for small, depressed gastric mucosal cancers with that of magnifying narrow-band imaging (M-NBI). METHODS We performed a multicenter, prospective, randomized, controlled trial of patients with undiagnosed depressed lesions ≤10 mm in diameter identified by esophagogastroduodenoscopy. Patients were randomly assigned to groups that were analyzed by C-WLI (n = 176) or M-NBI (n = 177) immediately after detection; the C-WLI group received M-NBI after C-WLI. We compared the diagnostic accuracy, sensitivity, and specificity between C-WLI and M-NBI and assessed the diagnostic yield of M-NBI conducted in conjunction with C-WLI. RESULTS Overall, 40 gastric cancers (20 in each group) were identified. The median diagnostic values for M-NBI and C-WLI were as follows: accuracy, 90.4% and 64.8%; sensitivity, 60.0% and 40.0%; and specificity, 94.3% and 67.9%, respectively. The accuracy and specificity of M-NBI were greater than those of C-WLI (P < .001); the difference in sensitivity was not significant (P = .34). The combination of M-NBI with C-WLI significantly enhanced performance compared with C-WLI alone; accuracy increased from (median) 64.8% to 96.6% (P < .001), sensitivity increased from 40.0% to 95.0% (P < .001), and specificity increased from 67.9% to 96.8% (P < .001). CONCLUSIONS M-NBI, in conjunction with C-WLI, identifies small, depressed gastric mucosal cancers with 96.6% accuracy, 95.0% sensitivity, and 96.8% specificity. These values are better than for C-WLI or M-NBI alone.

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.

An efficient diagnostic strategy for small, depressed early gastric cancer with magnifying narrow-band imaging: a post-hoc analysis of a prospective randomized controlled trial

BACKGROUND We previously reported that magnifying narrow-band imaging (M-NBI) is a high-performance diagnostic tool for small, depressed gastric cancer. However, an efficient diagnostic strategy using endoscopic findings has not been fully elucidated. OBJECTIVE To identify the endoscopic findings that contribute to accurate diagnosis of small, depressed gastric cancer and to propose the ideal diagnostic approach to such lesions. DESIGN Post-hoc analysis of a prospective, randomized, controlled trial. SETTING Nine hospitals. PATIENTS Three hundred fifty-three patients with small, depressed gastric lesions. INTERVENTIONS In the M-NBI group (n = 177), cancer diagnosis was made with diagnostic criteria including a demarcation line (DL) and an irregular microvascular pattern (IMVP). In the conventional white-light imaging (C-WLI) group (n = 176), diagnostic criteria were both an irregular margin and a spiny depressed area. In the C-WLI group, M-NBI was performed after C-WLI diagnosis. MAIN OUTCOME MEASUREMENTS The diagnostic performance of each criterion in M-NBI alone, C-WLI, and M-NBI after C-WLI was investigated. RESULTS M-NBI after C-WLI ultimately showed the best diagnostic performance in each diagnostic criterion. In M-NBI after C-WLI, evaluation of DL is technically easier than that of IMVP, and DL alone had a high sensitivity (95%) and negative predictive value (99%). The IMVP in M-NBI after C-WLI had a high sensitivity and specificity (95% and 96%, respectively) for diagnosis of cancer. LIMITATIONS Lesions were limited to the small, depressed type. CONCLUSIONS For a diagnosis using M-NBI after C-WLI, identification of DL is the first step, and subsequent inspection of IMVP diagnosed by DL is an efficient strategy.

Thienopyridine derivatives as risk factors for bleeding following high risk endoscopic treatments: Safe Treatment on Antiplatelets (STRAP) study.

BACKGROUND AND STUDY AIMS The optimal method of perioperative management of antiplatelet agents during endoscopic procedures that carry a high risk of bleeding is still controversial. The aim of this study was to evaluate the safety of continuing aspirin treatment during these procedures in an Asian population. PATIENTS AND METHODS A multicenter, prospective, observational cohort study was conducted at six high volume endoscopy centers in Japan. The study included patients at high risk of thromboembolism who were regularly taking antiplatelet agents (e. g. thienopyridine derivatives and aspirin). Enrolled patients continued their aspirin therapy, and underwent endoscopic procedures that had a high risk of bleeding for treatment of lesions in the upper and lower gastrointestinal tracts. The primary end point was the rate of major bleeding complications after endoscopic procedures. RESULTS The study was terminated in accordance with predetermined safety criteria because 7 of 28 consecutive patients experienced major bleeding complications (25.0 %; 95 % confidence interval 10.7 % - 44.9 %). All major bleeding complications occurred following endoscopic submucosal dissection (ESD; 6 stomach, 1 colon). Univariate analysis showed that postoperative administration of thienopyridine derivatives was the only significant factor associated with postoperative bleeding (P = 0.01). Subanalysis of gastric ESD (23 lesions in 19 patients) confirmed that the administration of thienopyridine derivatives (P = 0.01) and that of multiple agents (P = 0.02) were the significant factors. All bleeding complications (postoperative day 11.2 ± 3.5) occurred after resuming thienopyridine derivative therapy postoperatively (postoperative day 2.3 ± 2.4). CONCLUSION In Asian patients taking thienopyridine derivatives with aspirin, cautious postoperative care is necessary for those undergoing endoscopic procedures that are associated with a high risk of bleeding, especially gastric ESD. Continuation of aspirin alone during these endoscopic procedures may be acceptable. STUDY REGISTRATION UMIN000009176.

Endoscopic tissue shielding with polyglycolic acid sheets, fibrin glue and clips to prevent delayed perforation after duodenal endoscopic resection

The incidence of delayed perforation after endoscopic resection for superficial non‐ampullary duodenal epithelial tumors is extremely high. Endoscopic tissue shielding with polyglycolic acid (PGA) sheets and fibrin glue is a promising method to prevent delayed perforation after endoscopic resection in the duodenum. However, we often encounter difficulty when covering an artificial ulcer with PGA sheets after endoscopic resection. We report three cases of postoperative ulcers covered by PGA sheets, fibrin glue, and clips.

Detection of pharyngeal cancer in the overall population undergoing upper GI endoscopy by using narrow-band imaging: a single-center experience, 2009–2012

BACKGROUND Nonmagnifying observation by using narrow-band imaging (NBI) is useful for detecting pharyngeal lesions. Magnifying observation by using NBI can distinguish between cancerous and noncancerous lesions and is therefore useful for the early detection of pharyngeal cancer. OBJECTIVE To evaluate the usefulness of observation of the pharynx by using NBI in the overall population undergoing upper GI endoscopy. DESIGN Retrospective study. SETTING Single tertiary referral center. PATIENTS A total of 11,050 upper GI endoscopies between January 2009 and December 2012. INTERVENTIONS Observation of the pharynx by using NBI. MAIN OUTCOME MEASURES The rate of detection of pharyngeal cancer, the rates of detection according to the reason for endoscopy, and the types of cancers detected. RESULTS Thirty-eight cancerous lesions were detected in 29 patients (0.26%, 29/11,050). The rate of detection of pharyngeal cancer was significantly higher in patients with a history of head and neck cancer (9.7%, 3/31) or a history of esophageal cancer (3.5%, 10/282). In patients undergoing endoscopy for screening, pharyngeal discomfort, and a history of gastric cancer, the rates of detection of pharyngeal cancer were 0.11% (10/8872), 1.1% (3/265), and 0.19% (3/1600), respectively. Two patients (6.9%) were female. One had a history of esophageal cancer, and the other had pharyngeal discomfort. LIMITATIONS Single-center, retrospective study. CONCLUSIONS Observation of the pharynx by using NBI in patients with previous head and neck cancer or esophageal cancer or who have pharyngeal discomfort is very important. Moreover, pharyngeal cancer was certainly found in the male patients undergoing screening endoscopy, although the rate was lower.

Does Laparoscopic and Endoscopic Cooperative Surgery for Gastric Submucosal Tumors Preserve Residual Gastric Motility? Results of a Retrospective Single-Center Study

Background Laparoscopic and endoscopic cooperative surgery (LECS) is a minimally invasive surgical technique used to resect gastric submucosal tumors with intraluminal growth. Endoscopic submucosal dissection is used to determine the appropriate resection line from within the stomach lumen as it minimizes the stomach wall resection area and prevents postoperative stomach deformity. Although LECS is intended to preserve gastric function, few reports have evaluated postoperative residual gastric motility. Therefore, we conducted a retrospective analysis of patients who underwent LECS to determine the effects of LECS on residual gastric motility. Methods Twenty-two patients underwent endoscopy 3 to 12 months after LECS. Patients were evaluated for endoscopic evidence of gastric motility disorder, namely food residue and occurrence/exacerbation of reflux esophagitis. We considered patients with new onset of gastric symptoms and endoscopic evidence of gastric motility disorder to have clinically relevant gastric motility disorder. We described patient characteristics, tumor location, and surgical findings. Results Two of 22 patients developed clinically relevant gastric motility disorder after LECS. In one of these patients, the symptoms were not severe; only one had reduced dietary intake and had lost weight. We identified clinically relevant gastric motility disorder in two patients with gastrointestinal stromal tumors located in the lesser curvature of the stomach. The major axis of these two tumors was 34 mm and 38 mm. Conclusions Many patients did not have clinically relevant gastric motility disorder after LECS. Further investigation is required to identify predisposing factors for gastric motility disorder.

Preoperative endoscopic diagnosis of superficial non-ampullary duodenal epithelial tumors, including magnifying endoscopy.

Superficial non-ampullary duodenal epithelial tumor (SNADET) is defined as a sporadic tumor that is confined to the mucosa or submucosa that does not arise from Vaters papilla, and it includes adenoma and adenocarcinoma. Recent developments in endoscopic technology, such as high-resolution endoscopy and image-enhanced endoscopy, may increase the chances of detecting SNADET lesions. However, because SNADET is rare, little is known about its preoperative endoscopic diagnosis. The use of endoscopic resection for SNADET, which has no risk of metastasis, is increasing, but the incidence of complications, such as perforation, is significantly higher than in any other part of the digestive tract. A preoperative diagnosis is required to distinguish between lesions that should be followed up and those that require treatment. Retrospective studies have revealed certain endoscopic findings that suggest malignancy. In recent years, several new imaging modalities have been developed and explored for real-time diagnosis of these lesion types. Establishing an endoscopic diagnostic tool to differentiate between adenoma and adenocarcinoma in SNADET lesions is required to select the most appropriate treatment. This review describes the current state of knowledge about preoperative endoscopic diagnosis of SNADETs, such as duodenal adenoma and duodenal adenocarcinoma. Newer endoscopic techniques, including magnifying endoscopy, may help to guide these diagnostics, but their additional advantages remain unclear, and further studies are required to clarify these issues.

The “white globe appearance” (WGA): a novel marker for a correct diagnosis of early gastric cancer by magnifying endoscopy with narrow-band imaging (M-NBI)

Background and study aims: Although magnifying endoscopy with narrow-band imaging (M-NBI) is useful for the diagnosis of gastric mucosal lesions, differentiating between early cancer (EC) and low grade adenoma (LGA) remains a challenge. During M-NBI examination, we have noted the presence of a small, white lesion with a globular shape underneath cancerous gastric epithelium, and have termed this endoscopic finding the “white globe appearance” (WGA). The aim of this study was to determine whether or not the WGA could be an endoscopic marker for distinguishing EC from LGA. Methods: We retrospectively analyzed both the M-NBI scans and resected specimens of a total of 111 gastric lesions from 95 consecutive patients. Our main outcome was a difference in the prevalence of the WGA in EC and LGA. Results: The prevalence of the WGA in EC and LGA was 21.5 % (20 /93) and 0 % (0 /18), respectively (P = 0.039). The sensitivity, specificity, positive predictive value, and negative predictive value for differentiating between EC and LGA, according to the presence of the WGA, were 21.5, 100, 100, and 19.8 %, respectively. Conclusion: A positive WGA in a suspicious lesion on M-NBI would be an adjunct to the M-NBI diagnosis of possible EC because the specificity and positive predictive value of the WGA for differentiating between EC and LGA were extremely high. The WGA could be a novel endoscopic marker for differentiating between EC and LGA.

Recent traction methods for endoscopic submucosal dissection

Endoscopic mucosal resection (EMR) is problematic with regard to en bloc and curable resection rates. Advancements in endoscopic techniques have enabled novel endoscopic approaches such as endoscopic submucosal dissection (ESD), which has overcome some EMR problems, and has become the standard treatment for gastrointestinal tumors. However, ESD is technically difficult. Procedure time is longer and complications such as intraoperative perforation and bleeding occur more frequently than in EMR. Recently various traction methods have been introduced to facilitate ESD procedures, such as clip with line, external forceps, clip and snare, internal traction, double scope, and magnetic anchor. Each method must be used appropriately according to the anatomical characteristics. In this review we discuss recently proposed traction methods for ESD based on the characteristics of various anatomical sites.