Depth of the cutting plane with underwater and conventional endoscopic mucosal resection: Post-hoc analysis of a randomized study.

BACKGROUND AND AIM: A multicenter randomized controlled trial reported a better R0 resection rate for intermediate-sized (10-20 mm) colorectal polyps with underwater endoscopic mucosal resection (UEMR) than conventional endoscopic mucosal resection (CEMR). To clarify whether UEMR removes enough submucosal tissue in the removal of unpredictable invasive cancers, we investigated the cutting plane depth with UEMR versus CEMR. METHODS: This was a post-hoc analysis of a randomized controlled trial in which 210 intermediate-sized colorectal polyps were removed in five Japanese hospitals. One pathologist and two gastroenterologists independently reviewed all resected specimens and measured the cutting plane depth. The cutting plane depth was evaluated as (i) maximum depth of submucosal layer and (ii) mean depth of submucosal layer, calculated using a virtual pathology system. RESULTS: We identified 168 appropriate specimens for the evaluation of the cutting plane depth, resected by UEMR (n = 88) and CEMR (n = 80). The median resection depth was not significantly different between UEMR and CEMR specimens, regardless of the measurement method ([i] 1317 vs 1290 µm, P = 0.52; [ii] 619 vs 545 µm, P = 0.32). All specimens in the UEMR and CEMR groups contained substantial submucosa and no muscularis propria. CONCLUSIONS: The cutting plane depth with UEMR was comparable with that with CEMR. UEMR can be a viable alternative method that adequately resects the submucosal layer for the histopathological assessment of unpredictable submucosal invasive cancers.

Retrograde endoscopic submucosal dissection for early thoracic esophageal carcinoma.

Although the standard treatment for intramucosal esophageal cancer without lymph node metastasis is endoscopic submucosal dissection (ESD), we sometimes encounter patients who are not able to undergo a transoral endoscopic examination. Here, we report a surgical procedure consisting of transgastric retrograde ESD to treat early esophageal cancer (T1a-EP, N0, M0) because of a stricture after hypopharyngeal cancer surgery. This retrograde ESD procedure can be a safe and effective treatment option for early esophageal cancer. This is the first report of a surgical retrograde ESD method for esophageal cancer.

Helicobacter pylori eradication prevents secondary gastric cancer in patients with mild-to-moderate atrophic gastritis.

BACKGROUND AND AIM: Whether Helicobacter pylori eradication prevents metachronous recurrence after endoscopic resection (ER) of early gastric cancer remains controversial. This multicenter retrospective study aimed to evaluate the long-term (> 5 years) effects of H. pylori eradication by stratifying patients' baseline degrees of atrophic gastritis. METHODS: A total of 483 H. pylori-positive patients who had undergone ER for early gastric cancer were divided into two groups-(i) those having undergone successful H. pylori eradication within 1 year after ER (eradicated group, n = 294) and (ii) those with failed or not attempted H. pylori eradication (non-eradicated group, n = 189). The cumulative incidences of metachronous gastric cancer between the two groups were compared for all patients, for patients with mild-to-moderate atrophic gastritis (n = 182), and for patients with severe atrophic gastritis (n = 301). RESULTS: During a median follow-up of 5.2 years (range 1.1-14.8), metachronous cancer developed in 52 (17.7%) patients in the eradicated group and in 35 (18.5%) patients in the non-eradicated group (P = 0.11, log-rank test). In patients with mild-to-moderate atrophic gastritis (111 and 71 in the eradicated and non-eradicated groups, respectively), the cumulative incidence of metachronous cancer was significantly lower in the eradicated group than that in the non-eradicated group (P = 0.03, log-rank test). However, no significant intergroup difference was observed in patients with severe atrophic gastritis (P = 0.69, log-rank test). CONCLUSIONS: Helicobacter pylori eradication had a preventive effect on the development of metachronous gastric cancer in patients with mild-to-moderate atrophic gastritis.

Prophylactic clipping not effective in preventing post-polypectomy bleeding for < 20-mm colon polyps: A multicenter, open-label, randomized controlled trial.

BACKGROUND AND AIM: Prophylactic clipping (PC) after polypectomy has the potential to prevent post-polypectomy bleeding (PPB). We aimed to evaluate the effectiveness of PC in preventing PPB for < 20-mm polyps. METHODS: This multicenter, open-label, randomized controlled trial conducted from December 2013 to June 2017 at 10 institutions randomly assigned 1080 patients with < 20-mm colon polyps to the non-PC and PC groups. Allocation factors were institution, antiplatelet drug use, and polyp number. The primary endpoint was differences in PPB rates between the groups. The severity of PPB and post-procedural abdominal symptoms were also investigated. These endpoints in intention-to-treat and per-protocol (PP) analyses were evaluated. RESULTS: We investigated 1039 patients with 2960 lesions. There was no significant difference between the groups in characteristics including age, sex, hypertension, diabetes, hyperlipidemia, antiplatelet drug use, and lesion characteristics such as type and size. Excluding the clip used in the non-PC group, intraoperative bleeding, and deviation of protocol, 903 patients were investigated in PP analysis. There was no significant difference in the PPB rate between the non-PC and PC groups (2.7% vs 2.3%, P = 0.6973 [intention-to-treat analysis]; 3.0 vs 2.4%, P = 0.7353 [PP analysis]). Severe PPB (≥ grade 3) was similar between the groups. Total procedure time was significantly shorter in the non-PC group than in the PC group (31 vs 36 min, P = 0.0002). Post-procedural abdominal fullness was less common in the non-PC group than in the PC group (20.8% vs 25.6%, P = 0.0833). CONCLUSION: Prophylactic clipping is not effective in preventing PBB for < 20-mm colon polyps (UMIN000012163).

[A case of idiopathic thrombocytopenic purpura development after total colectomy for ulcerative colitis].

Ulcerative colitis (UC) is known to be associated with extraintestinal manifestations. However, idiopathic thrombocytopenic purpura (ITP) has rarely been reported as one of the extraintestinal manifestations in UC. In most cases, ITP develops as an extraintestinal manifestation during the treatment for UC. After treatment with medications or colectomy, there is often a remission of UC and ITP. However, we experienced a case of ITP development after total colectomy for UC. An 83-year-old man was diagnosed as having UC and started treatment with medications. After 3 years, total colectomy and ileostomy were performed to prevent UC remission. Subsequently, no further treatment was provided. Two years later, he presented to the hematology department in our hospital with the chief complaint of thrombocytopenia and was diagnosed as having ITP. ITP was treated with steroids, and his platelet count increased to within the normal range. Immunological abnormalities may be involved in the development of extraintestinal manifestation, including UC-associated ITP. In previous reports, ITP was cured by colectomy for UC. In contrast, peripheral arthritis is a common extraintestinal manifestation of UC, and it is known that 75% of these patients develop or continue to experience such symptoms after colectomy. Some extraintestinal manifestations may equally persist after colectomy. However, the underlying mechanisms are poorly understood. Ileitis and small intestinal and duodenal inflammation are all known bowel complications associated with colectomy, and some immunological mechanisms have been suggested to be involved. Therefore, careful monitoring in these patients is necessary to detect any possibility of developing extraintestinal manifestations after colectomy. Further studies to examine the mechanisms underlying the immunological abnormality between UC and extraintestinal manifestations such as ITP are needed.

Differentiation between duodenal neoplasms and non-neoplasms using magnifying narrow-band imaging - Do we still need biopsies for duodenal lesions?

OBJECTIVES: Endoscopic biopsies for nonampullary duodenal epithelial neoplasms (NADENs) can induce submucosal fibrosis, making endoscopic resection difficult. However, no biopsy-free method exists to distinguish between NADENs and non-neoplasms. We developed a diagnostic algorithm for duodenal neoplasms based on magnifying endoscopy findings and evaluated the model's diagnostic ability. METHODS: Magnified endoscopic images and duodenal lesion histology were collected consecutively between January 2015 and April 2016. Diagnosticians classified the surface patterns as pit, groove or absent. In cases of nonvisible surface patterns, the vascular pattern was evaluated to determine regularity or irregularity. The correlation between our algorithm (pit-type or absent with irregular vascular pattern) and the lesion histology were evaluated. Four evaluators, who were blinded to the histology, also classified the endoscopic findings and evaluated the diagnostic performance and interobserver agreement. RESULTS: Endoscopic images of 114 lesions were evaluated (70 NADENs and 44 non-neoplasms, 31 in the superior and 83 in the descending and horizontal duodenum). Of the NADEN surface patterns, 88% (62/70) were pit-type, while 79% (35/44) of the non-neoplasm surface patterns were groove-type. Our diagnostic algorithm for differentiating NADENs from non-neoplasms was high (sensitivity 96%, specificity 95%) in the descending and horizontal duodenum. The evaluators' diagnostic performances were also high, and interobserver agreement for the algorithm was good between each diagnostician and evaluator (κ = 0.60-0.76). CONCLUSION: Diagnostic performance of our algorithm sufficiently enabled eliminating endoscopic biopsies for diagnosing the descending and horizontal duodenum.

Endoscopic appearance of esophageal xanthoma.

Background and study aims Esophageal xanthomas are considered to be rare, and their endoscopic diagnosis has not been fully elucidated. The aim of the present study was to determine the characteristics of the endoscopic appearance of esophageal xanthomas. Patients and methods This was a retrospective study of consecutive patients with histologically diagnosed esophageal xanthomas at a referral cancer center in Japan. The endoscopic appearance, by magnifying or image-enhanced endoscopy, and histological findings of esophageal xanthomas were investigated. Results Seven patients (six men and one woman) were enrolled. All of the patients had a solitary lesion, and the median size was 2 mm (range, 1 - 5 mm). Conventional white-light endoscopy showed the lesions as flat areas with yellowish spots in four cases and slightly elevated yellowish lesions in three cases. Magnifying endoscopy, performed in six patients, revealed the lesions as areas with aggregated minute yellowish spots with tortuous microvessels inside. Magnifying narrow-band imaging contrasted the yellowish spots and microvessels better than white-light endoscopy. In all lesions, histological examination showed that the yellowish spots corresponded to papillae filled with foam cells. The foam cells were strongly immunopositive for CD68, and in all lesions, CD34-positive intrapapillary capillaries surrounded the aggregated foam cells. The different morphologies of the flat and slightly elevated lesions corresponded to different densities of papillae filled with foam cells. Conclusions Magnifying endoscopy revealed minute yellowish spots with tortuous microvessels inside. These correspond well with histological findings and so may be useful in the diagnosis of esophageal xanthomas.

[A case of refractory pouchitis following surgery for ulcerative colitis successfully treated with adalimumab].

Restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) is widely accepted as the operation of choice for refractory ulcerative colitis (UC), UC with dysplasia or cancer, or familial adenomatous polyposis. Pouchitis is the most frequent complication after IPAA for UC. Although the pathogenesis of pouchitis remains unclear, current evidence suggests that dysbiosis and mucosal immune response are important mechanisms. Antibiotics are the first-line treatment for the condition, but some patients develop chronic refractory pouchitis. Such cases can be treated with regimens such as longer courses of antibiotic combinations, mesalazine, corticosteroids, probiotics, or biologics. But if pouch inflammation is not ameliorated, a permanent ileostomy may be required. A 40-year-old man had undergone IPAA for UC and was diagnosed with pouchitis according to the Pouchitis Disease Activity Index. Antibiotics, mesalazine, and corticosteroids were given, but the inflammation was difficult to control. He developed chronic refractory pouchitis associated with perianal abscesses and anal fistulae. Following a seton procedure for fistulae, adalimumab (ADA) was administered. After 42 weeks, the ulcers in the pouch became scarred, and the anal fistulae were closed endoscopically. After remission was induced, it has been maintained. ADA is a fully human anti-tumor necrosis factor-α (TNF-α) monoclonal antibody that has been successfully used to treat refractory Crohn disease of the ileoanal pouch. Although some studies report that infliximab, a chimeric anti-TNF-α monoclonal antibody, is efficacious in patients with refractory pouchitis, clinical evidence for the use of ADA is limited. This case illustrates achievement of induction and maintenance of remission of refractory pouchitis with ADA. It is possible that patients with this condition can avoid a permanent ileostomy with anti-TNF-α therapy. In the near future, further study of long-term clinical outcomes of anti-TNF-α therapy is expected.

Self-study of the non-extension sign in an e-learning program improves diagnostic accuracy of invasion depth of early gastric cancer.

Background and study aims We developed an e-learning program for endoscopic diagnosis of invasion depth of early gastric cancer (EGC) using a simple diagnostic criterion called non-extension sign, and the contribution of self-study quizzes to improvement of diagnostic accuracy was evaluated. Methods We conducted a prospective randomized controlled study that recruited endoscopists throughout Japan. After completing a pretest, the participants watched video lectures and undertook post-test 1. The participants were then randomly allocated to either the self-study or non-self-study group, and participants in the first group completed the self-study program that comprised 100-case quizzes. Finally, participants in both groups undertook post-test 2. The primary endpoint was the difference in post-test 2 scores between the groups. The perfect score for the tests was set as 100 points. Results A total of 423 endoscopists completed the pretest and were enrolled. Post-test 1 was completed by 415 endoscopists and 208 were allocated to the self-study group and 207 to the non-self-study group. Two hundred and four in the self-study group and 205 in the non-self-study group were included in the analysis. Video lectures improved the mean score of post-test 1 from 72 to 77 points. Participants who completed the self-study quizzes showed significantly better post-test 2 scores compared with the non-self-study group (80 vs. 76 points, respectively, P  < 0.0001). Conclusions Our e-learning program showed that self-study quizzes consolidated knowledge of the non-extension sign and improved diagnostic ability of endoscopists for invasion depth of EGC.

Favorable outcome with direct-acting antiviral treatment in hepatitis C patients coinfected with HIV.

AIM: To investigate the efficacy and safety of all-oral direct-acting antiviral treatments in patients coinfected with hepatitis C virus (HCV) and HIV. METHODS: In all, 35 patients with HCV/HIV coinfection (22 patients with HCV genotype 1 infection, 6 with genotype 2, and 7 with genotype 3) were treated with sofosbuvir and ledipasvir (for genotype 1 patients) or sofosbuvir and ribavirin (for genotypes 2 and 3). Sustained virological response (SVR) at 24 weeks after end of treatment and adverse events were assessed. RESULTS: The overall SVR rate was 91.4% (32/35). One patient with genotype 1 infection discontinued treatment on day 2 due to severe headache, which subsided after the cessation of medication; all other patients completed their treatment without severe adverse events. Two patients who had a relapse of HCV were infected with a genotype 3 strain. We observed hyperbilirubinemia in a patient with genotype 3, who was under antiretroviral therapy including atazanavir. He completed the treatment and achieved SVR. CONCLUSION: Direct-acting antiviral treatment for patients coinfected with HCV/HIV is as effective as in patients infected only with HCV. It was generally well tolerated, except in one patient who discontinued the treatment due to severe headache.

Comparison of Underwater vs Conventional Endoscopic Mucosal Resection of Intermediate-Size Colorectal Polyps.

BACKGROUND & AIMS: Endoscopic mucosal resection (EMR) with submucosal injection is an established method for removing colorectal polyps, although the en bloc resection rate decreases when polyp size exceeds 10 mm. Piecemeal resection increases local recurrence. Underwater EMR (UEMR) is an effective technique for removal of sessile colorectal polyps and we investigated whether it is superior to conventional EMR (CEMR). METHODS: We conducted a multicenter randomized controlled trial at 5 institutions in Japan. Patients with endoscopically diagnosed, intermediate-size (10-20 mm) sessile colorectal lesions were randomly assigned to undergo UEMR or CEMR. Only the most proximal lesion was registered. The UEMR procedure included immersion of the entire lumen in water and snare resection of the lesion without submucosal injection of normal saline. We analyzed outcomes of 108 colorectal lesions in the UEMR group and 102 lesions in the CEMR group. R0 resection was defined as en bloc resection with a histologically confirmed negative resection margin. The primary endpoint was the difference in the R0 resection rates between groups. RESULTS: The proportions of R0 resections were 69% (95% confidence interval [CI] 59%-77%) in the UEMR group vs 50% (95% CI 40%-60%) in the CEMR group (P = .011). The proportions of en bloc resections were 89% (95% CI 81%-94%) in the UEMR group vs 75% (95% CI 65%-83%) in the CEMR group (P = .007). There was no significant difference in median procedure time (165 vs 175 seconds) or proportions of patients with adverse events (2.8% in the UEMR group vs 2.0% in the CEMR group). CONCLUSIONS: In a multicenter randomized controlled trial, we found that UEMR significantly increased the proportions of R0 resections for 10- to 20-mm sessile colorectal lesions without increasing adverse events or procedure time. Use of this procedure should be encouraged. Trials registry number: UMIN000018989.

A prospective multicenter observational study evaluating the risk of periendoscopic events in patients using anticoagulants: the Osaka GIANT Study.

Background and study aims An increasing number of patients have been using anticoagulants including anti-vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs); however, in patients using anticoagulants, limited data are available with regard to the risks of gastrointestinal bleeding and thromboembolic events during the peri-endoscopic period. We aimed to evaluate the peri-endoscopic bleeding and thrombotic risks in patients administered VKAs or DOACs. Patients and methods Consecutive patients using anticoagulants who underwent endoscopic biopsy, mucosal resection, or submucosal dissection were prospectively enrolled across 11 hospitals. The primary outcome assessed was difference in incidence of post-procedural gastrointestinal bleeding in patients using VKAs and DOACs. Duration of hospitalization and peri-procedural thromboembolic events were also compared. Results We enrolled 174 patients using VKAs and 37 using DOACs. In total, 16 patients using VKA were excluded from the analysis because of cancellation of endoscopic procedures and contraindications to the use of DOACs; 128 (81 %) patients using VKAs and 17 (46 %) using DOACs received heparin-bridging therapy (HB). The rate of post-procedural gastrointestinal bleeding in DOAC users was similar to that in VKA users (16.2 % vs. 16.4 %, P  = 1.000). Duration of hospitalization was significantly longer in patients using VKAs than in those using DOACs (median 15 vs. 7 days, P  < 0.0001). Myocardial infarction occurred during pre-endoscopic HB in one patient using VKAs. Conclusion DOAC administration showed similar post-procedural gastrointestinal bleeding risk to VKA administration in patients undergoing endoscopic procedures, but it shortened the hospital stay.

Sporadic Minute Pharyngeal Xanthomas Detected Incidentally During Esophagogastroduodenoscopy: A Case Series.

Pharyngeal xanthomas are considered rare, and no reports have described their endoscopic appearance under magnifying or image-enhanced endoscopy. We report three cases of asymptomatic sporadic pharyngeal xanthoma that were detected incidentally during routine esophagogastroduodenoscopy. All the patients were men and had a solitary lesion of about 1 mm in size. Two of the lesions were located in the oropharynx, while one was in the hypopharynx. Non-magnifying endoscopy showed yellowish lesions, and magnifying endoscopy showed an aggregation of minute yellowish nodules with tortuous microvessels on their surface. Histopathological examination revealed foam cells filling the intraepithelial papillae. The foam cells were strongly immunopositive for cluster of differentiation (CD) 68. Immunohistochemical staining for CD34 showed intrapapillary capillaries around the foam cells. This characteristic magnifying endoscopic appearance corresponded to the histopathological findings of pharyngeal xanthomas. The present cases reveal the relationship between the endoscopic appearance and histopathological findings of pharyngeal xanthomas.

Efficacy of vonoprazan in prevention of bleeding from endoscopic submucosal dissection-induced gastric ulcers: a prospective randomized phase II study.

BACKGROUND: Vonoprazan, potassium-competitive acid blocker, is expected to reduce incidence of delayed bleeding after gastric endoscopic submucosal dissection (ESD); however, preliminary data to design a large-scale comparative study are lacking. This study aimed to assess the efficacy of vonoprazan in preventing delayed bleeding after gastric ESD. METHODS: In this single-center randomized phase II trial, a modified screened selection design was used with a threshold non-bleeding rate of 89% and an expected rate of 97%. In this design, Simon's optimal two-stage design was first applied for each parallel group, and efficacy was evaluated in comparison with the threshold rate using binomial testing. Patients were randomly assigned in a 1:1 ratio to receive either vonoprazan 20 mg (VPZ group) or lansoprazole 30 mg (PPI group) for 8 weeks from the day before gastric ESD. The primary endpoint was the incidence of delayed bleeding, defined as endoscopically confirmed bleeding accompanied by hematemesis, melena, or a decrease in hemoglobin of ≥ 2 g/dl. RESULTS: Delayed bleeding occurred in three of 69 patients (4.3%, 95% CI 0.9-12.2%, p = 0.047) in the VPZ group, and four of 70 (5.7%, 95% CI 1.6-14.0%, p = 0.104) in the PPI group. As only vonoprazan showed significant reduction in delayed bleeding compared with the threshold rate, it was determined to be efficacious treatment. CONCLUSIONS: Vonoprazan efficaciously reduced the delayed bleeding rate in patients with an ESD-induced gastric ulcer. A large-scale, randomized, phase III study is warranted to definitively test the effectiveness of vonoprazan compared with proton pump inhibitors.

Endoscopic Balloon Dilation Followed By Intralesional Steroid Injection for Anastomotic Strictures After Esophagectomy: A Randomized Controlled Trial.

OBJECTIVE: Endoscopic balloon dilation (EBD) is a standard treatment for anastomotic strictures after esophagectomy, and requires multiple dilations. We conducted a randomized controlled trial to assess the efficacy of adding a steroid injection to EBD to reduce restricture. METHODS: Patients were randomized to receive EBD combined with either triamcinolone or placebo injection. The primary endpoint was the number of dilations required to resolve the stricture. The secondary endpoints were restricture-free survival and adverse events. Patients with a dysphagia symptom score of ≥2 after esophagectomy with an endoscopy-confirmed anastomotic stricture were included. A total of 50 mg of triamcinolone acetonide (50 mg/5 mL) or an identical volume of normal saline solution as a placebo was injected per site using a 25-gauge needle immediately after EBD. Both the patient and treating physician were blinded to the treatment given. RESULTS: During the 4-year study period, 65 patients were randomized to either the steroid group (n = 33) or placebo group (n = 32). The median number of EBDs required to resolve strictures was 2.0 (interquartile range, 1.0-2.5) in the steroid group and 4.0 (interquartile range, 2.0-6.8) in the placebo group (p < 0.001). After 6 months of follow-up, 39% of patients who had received steroid injections remained recurrence free compared with 16% of those who had received saline injections (p = 0.002). No adverse events occurred during follow-up. CONCLUSIONS: Steroid injection shows promising results for the prevention of stricture recurrence in patients who underwent EBD for anastomotic strictures.

"Underwater" endoscopic submucosal dissection: a novel method for resection in saline with a bipolar needle knife for colorectal epithelial neoplasia.

BACKGROUND: Despite improvements in therapeutic strategy and instrumentation in colorectal endoscopic submucosal dissection (ESD), adverse events sometimes occur. Further advancements in available techniques are required to improve procedural success rates and safety. We developed a novel method for ESD in saline, referred to as "underwater" ESD (UESD). UESD involves using a bipolar needle knife and aims to enable complete resection while minimizing thermal damage to the muscle layer. In this study, we evaluated the safety and efficacy of this new technique. METHODS: This was a retrospective study using data from two referral centers and included 40 lesions diagnosed as colorectal epithelial neoplasia (> 20 mm in diameter or with severe fibrosis) and treated with UESD between December 2015 and March 2017. The main outcome measures were technical success rate, incidence of adverse events, and feasibility of histologic evaluation of the resected specimens. RESULTS: All 40 lesions, including those with submucosal fibrosis, underwent successful en bloc resection using the UESD technique. No procedural adverse events including perforation, delayed bleeding, and electrocoagulation syndrome were observed, and all patients had an uneventful clinical course associated with UESD. In all cases, UESD provided a resected specimen adequate for histological evaluation, without unwarranted burn effect to the tissues. CONCLUSIONS: Our UESD technique was safe and effective for complete resection of colorectal epithelial neoplasia.

Transoral endoscopic examination of head and neck region.

Transoral endoscopy with narrow band imaging (NBI) is useful for early detection of head and neck (HN) cancer. However, the lateral and anterior walls of the oropharynx, postcricoid area, and posterior wall of the hypopharynx are difficult to observe using transoral endoscopy. Advanced cancers in these regions may be missed even when NBI is used. This report highlights a method of transoral endoscopic examination of the HN region. For observation of the oral cavity and oropharynx, it is important to observe these regions without using a mouthpiece. Wide opening of the mouth facilitates observation of the oral cavity and oropharynx. Moreover, visibility of the oropharynx, including the anterior wall, is dramatically improved, when the patient positions the tongue forward and says 'aaah.' This technique also facilitates observation of the dorsum of the tongue, which is difficult to observe from a tangential view when using a mouthpiece. To observe the hypopharynx, the Valsalva maneuver is very useful. Patient cooperation is important when observing the HN region thoroughly to gain clear endoscopic views. Narcotic drugs, such as pethidine hydrochloride, are ideal for conscious sedation and reduce the gag reflex while still allowing patient cooperation. From the oral cavity to the hypopharynx, including the lateral and anterior walls of the oropharynx, postcricoid area, and posterior wall of the hypopharynx, most of the HN region can be observed during routine examination using transoral endoscopy without any special devices.