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Dive into the research topics where Hiroyoshi Nakanishi is active.

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Featured researches published by Hiroyoshi Nakanishi.


Gastrointestinal Endoscopy | 2014

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

Hiroyoshi Nakanishi; Hisashi Doyama; Kenichi Takemura; Naohiro Yoshida; Kunihiro Tsuji; Yasuhito Takeda; Yoshiro Asahina; Yosuke Kito; Renma Ito; Tomoyuki Hayashi; Katsura Hirano; Yoshinori Goto; Kei Tominaga; Satoko Inagaki; Yohei Waseda; Shigetsugu Tsuji; Kazuhiro Miwa; Yoshibumi Kaneko; Shinya Yamada; Hiroshi Kurumaya; Makoto Sakumoto; Toshihide Okada

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.


PLOS ONE | 2014

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

Yohei Waseda; Hisashi Doyama; Noriyuki Inaki; Hiroyoshi Nakanishi; Naohiro Yoshida; Shigetsugu Tsuji; Kenichi Takemura; Shinya Yamada; Toshihide Okada

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.


Endoscopy International Open | 2015

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)

Hisashi Doyama; Naohiro Yoshida; Sho Tsuyama; Ryosuke Ota; Yasuhito Takeda; Hiroyoshi Nakanishi; Kunihiro Tsuji; Kei Tominaga; Shigetsugu Tsuji; Kenichi Takemura; Shinya Yamada; Kazuyoshi Katayanagi; Hiroshi Kurumaya; Akinori Iwashita; Kenshi Yao

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.


World Journal of Gastroenterology | 2016

Recent traction methods for endoscopic submucosal dissection

Kunihiro Tsuji; Naohiro Yoshida; Hiroyoshi Nakanishi; Kenichi Takemura; Shinya Yamada; Hisashi Doyama

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.


Digestive Endoscopy | 2016

White globe appearance is a novel specific endoscopic marker for gastric cancer: A prospective study

Naohiro Yoshida; Hisashi Doyama; Hiroyoshi Nakanishi; Kunihiro Tsuji; Kei Tominaga; Kazuhiro Matsunaga; Shigetsugu Tsuji; Kenichi Takemura; Shinya Yamada; Sho Tsuyama; Kazuyoshi Katayanagi; Hiroshi Kurumaya

White globe appearance (WGA) is a small white lesion with a globular shape that can be identified by magnifying endoscopy with narrow‐band imaging (M‐NBI). WGA was recently reported as a novel endoscopic marker that can differentiate between gastric cancer (GC) and low‐grade adenoma. However, the usefulness of WGA for differentiating GC from non‐cancerous lesions (NC), including those of gastritis, is unknown.


Digestive Endoscopy | 2014

Use of transoral endoscopy for pharyngeal examination: Cross‐sectional analysis

Kunihiro Tsuji; Hisashi Doyama; Yasuhito Takeda; Kenichi Takemura; Naohiro Yoshida; Yosuke Kito; Yoshiro Asahina; Renma Ito; Hiroyoshi Nakanishi; Tomoyuki Hayashi; Satoko Inagaki; Kei Tominaga; Yohei Waseda; Shigetsugu Tsuji; Shinya Yamada; Shoryoku Hino; Toshihide Okada

Transoral endoscopy with narrow band imaging (NBI) is useful for identifying early‐stage head and neck cancer. However, the screening capability of transoral upper gastrointestinal endoscopy has not yet been systematically evaluated. We evaluated the usefulness of transoral upper gastrointestinal endoscopy for pharyngeal examination.


Digestive Endoscopy | 2014

Can flat-type brownish microlesions in the orohypopharynx be followed up without biopsy or endoscopic resection?

Kenichi Takemura; Hisashi Doyama; Hiroyoshi Nakanishi; Yasuhito Takeda; Yosuke Kito; Renma Ito; Tomoyuki Hayashi; Kunihiro Tsuji; Kei Tominaga; Naohiro Yoshida; Yohei Waseda; Shigetsugu Tsuji; Shinya Yamada; Hideki Niwa; Kazuyoshi Katayanagi; Hiroshi Kurumaya; Toshihide Okada

Narrow‐band imaging (NBI) is useful for detecting superficial oropharyngeal lesions. However, the diagnostic and treatment guidelines for NBI are not established. The aim of the present study was to evaluate the treatment strategy for these microlesions.


World Journal of Gastrointestinal Endoscopy | 2016

Effectiveness of clip-and-snare method using pre-looping technique for gastric endoscopic submucosal dissection

Naohiro Yoshida; Hisashi Doyama; Ryosuke Ota; Yasuhito Takeda; Hiroyoshi Nakanishi; Kei Tominaga; Shigetsugu Tsuji; Kenichi Takemura

AIM To evaluate efficacy and safety of clip-and-snare method using pre-looping technique (CSM-PLT) for gastric endoscopic submucosal dissection (ESD). METHODS In the CSM-PLT method, a clip attached to the lesion side was strangulated with a snare, followed by application of an appropriate tension to the lesion independent of an endoscope. Twenty consecutive lesions were resected by ESD using CSM-PLT (CSM-PLT group) and compared with a control group, including 20 lesions that were resected by conventional ESD. The control group was matched based on the size and location of the lesion, presence of pathologic fibrosis, and experience of endoscopists. Total procedure time of ESD, proportion of en bloc resection, and complications were analyzed. RESULTS The total procedure time for the CSM-PLT group was significantly shorter than that for the control group (38.5 min vs 59.5 min, P = 0.023); all lesions were resected en bloc by ESD. There was no significant difference in complications between the two groups. Moreover, there was no complication in the CSM-PLT group. In one large lesion (size: 74 mm) that underwent extensive CSM-PLT during ESD, we used an additional CSM-PLT on another edge of the lesion after achieving submucosal resection to the maximum extent possible during initial CSM-PLT. In two lesions, the snare came off the lesion together with the clip after a sudden pull; nevertheless, ESD was successful in all lesions. CONCLUSION CSM-PLT was an effective and safe method for gastric ESD.


Annals of Gastroenterology | 2016

Importance of colonoscopy in patients undergoing endoscopic resection for superficial esophageal squamous cell carcinoma

Kei Tominaga; Hisashi Doyama; Hiroyoshi Nakanishi; Naohiro Yoshida; Yasuhito Takeda; Ryosuke Ota; Kunihiro Tsuji; Kazuhiro Matsunaga; Shigetsugu Tsuji; Kenichi Takemura; Shinya Yamada; Kazuyoshi Katayanagi; Hiroshi Kurumaya

Background The aim of the study was to clarify the frequency of colorectal neoplasm (CRN) complicating superficial esophageal squamous cell carcinoma (ESCC) and the need for colonoscopy. Methods We retrospectively reviewed 101 patients who had undergone initial endoscopic resection (ER) for superficial ESCC. Control group participants were age- and sex-matched asymptomatic subjects screened at our hospital over the same period of time. Advanced adenoma was defined as an adenoma ≥10 mm, with villous features, or high-grade dysplasia. Advanced CRN referred to advanced adenoma or cancer. We measured the incidence of advanced CRN in superficial ESCC and controls, and we compared the characteristics of superficial ESCC patients with and without advanced CRN. Results In the superficial ESCC group, advanced CRNs were found in 17 patients (16.8%). A history of smoking alone was found to be a significant risk factor of advanced CRN [odds ratio 6.02 (95% CI 1.30-27.8), P=0.005]. Conclusion The frequency of synchronous advanced CRN is high in superficial ESCC patients subjected to ER. Colonoscopy should be highly considered for most patients who undergo ER for superficial ESCC with a history of smoking, and is recommended even in superficial ESCC patients.


Gastric Cancer | 2012

Can magnifying endoscopy with narrow band imaging be useful for low grade adenomas in preoperative biopsy specimens

Kazuhiro Miwa; Hisashi Doyama; Renma Ito; Hiroyoshi Nakanishi; Katsura Hirano; Satoko Inagaki; Kei Tominaga; Naohiro Yoshida; Kenichi Takemura; Shinya Yamada; Yoshibumi Kaneko; Kazuyoshi Katayanagi; Hiroshi Kurumaya; Toshihide Okada; Masakazu Yamagishi

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Shinya Yamada

Kyoto Prefectural University of Medicine

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Naohiro Yoshida

Tokyo Institute of Technology

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