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Dive into the research topics where Yasunori Otowa is active.

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Featured researches published by Yasunori Otowa.


Diseases of The Esophagus | 2016

Changes in modified Glasgow prognostic score after neoadjuvant chemotherapy is a prognostic factor in clinical stage II/III esophageal cancer

Yasunori Otowa; Tetsu Nakamura; Gosuke Takiguchi; Ayako Tomono; Masashi Yamamoto; Shingo Kanaji; Tatsuya Imanishi; Satoshi Suzuki; Kenichi Tanaka; Tomoo Itoh; Yoshihiro Kakeji

The inflammation-based modified Glasgow prognostic score (mGPS) has been shown to be a prognostic factor for esophageal cancer, but its changes in relation to neoadjuvant chemotherapy (NAC) have never been discussed. The purpose of this study was to evaluate the potential prognostic role of mGPS with regard to NAC. mGPS was evaluated on the basis of admission blood samples taken before chemotherapy and before surgery. Patients with elevated C-reactive protein (CRP) serum levels (>10 mg/L) and hypoalbuminemia (<35 g/L) were allocated a score of 2, patients with elevated CRP serum levels without hypoalbuminemia were allocated a score of 1, and patients with normal CRP serum levels with or without hypoalbuminemia were allocated a score of 0. A total of 100 patients with clinical stage II/III squamous cell esophageal cancer, who underwent NAC and esophagectomy between January 2007 and August 2012, were investigated. From the multivariate analysis, the grade of response to chemotherapy and post-NAC mGPS level was found to be independent prognostic factors. The overall survival rate was significantly higher in the conserved mGPS group than in the worse mGPS group (P = 0.030). Changes in mGPS during chemotherapy affected the prognosis of patients, and post-NAC mGPS is an independent prognostic factor in patients with clinical stage II/III thoracic esophageal squamous cell cancer.The inflammation-based modified Glasgow prognostic score (mGPS) has been shown to be a prognostic factor for esophageal cancer, but its changes in relation to neoadjuvant chemotherapy (NAC) have never been discussed. The purpose of this study was to evaluate the potential prognostic role of mGPS with regard to NAC. mGPS was evaluated on the basis of admission blood samples taken before chemotherapy and before surgery. Patients with elevated C-reactive protein (CRP) serum levels (>10 mg/L) and hypoalbuminemia (<35 g/L) were allocated a score of 2, patients with elevated CRP serum levels without hypoalbuminemia were allocated a score of 1, and patients with normal CRP serum levels with or without hypoalbuminemia were allocated a score of 0. A total of 100 patients with clinical stage II/III squamous cell esophageal cancer, who underwent NAC and esophagectomy between January 2007 and August 2012, were investigated. From the multivariate analysis, the grade of response to chemotherapy and post-NAC mGPS level was found to be independent prognostic factors. The overall survival rate was significantly higher in the conserved mGPS group than in the worse mGPS group (P = 0.030). Changes in mGPS during chemotherapy affected the prognosis of patients, and post-NAC mGPS is an independent prognostic factor in patients with clinical stage II/III thoracic esophageal squamous cell cancer.


World Journal of Gastroenterology | 2014

Appendicitis with psoas abscess successfully treated by laparoscopic surgery.

Yasunori Otowa; Yasuo Sumi; Shingo Kanaji; Kiyonori Kanemitsu; Kimihiro Yamashita; Tatsuya Imanishi; Tetsu Nakamura; Satoshi Suzuki; Kenichi Tanaka; Yoshihiro Kakeji

Although acute appendicitis is a common disease, retroperitoneal abscesses are rarely observed. Here, we report a case consisting of a psoas abscess and cutaneous fistula caused by appendicitis. The patient was a 56-year-old male who was introduced to our institution due to an intractable right psoas abscess. Imaging tests had been performed over the previous 3 years; however, clinicians could not find the origin of the abscess and failed to resolve the problem. A successful operation was performed via a laparoscopic approach, and 17 mo have passed without recurrence. The advantage of laparoscopic surgery is well understood in cases of appendicitis with abscesses. However, the indication for laparoscopic approach is not clear for retroperitoneal abscesses. From our experience, we can conclude that appendicitis with retroperitoneal abscesses can be managed and treated using a laparoscopic approach.


OncoTargets and Therapy | 2015

Treating patients with advanced rectal cancer and lateral pelvic lymph nodes with preoperative chemoradiotherapy based on pretreatment imaging

Yasunori Otowa; Kimihiro Yamashita; Kiyonori Kanemitsu; Yasuo Sumi; Masashi Yamamoto; Shingo Kanaji; Tatsuya Imanishi; Tetsu Nakamura; Satoshi Suzuki; Kenichi Tanaka; Yoshihiro Kakeji

Preoperative chemoradiotherapy (CRT) and lateral pelvic lymph node (LPLN) dissection (LPLD) based on pretreatment imaging are performed to improve oncological outcomes at our institution. However, the advantage of LPLD following preoperative CRT in advanced rectal cancer remains unclear. The objective of the present study was to assess the validity of this approach. Thirty-two patients with advanced rectal cancer were included in the study. All patients were treated with preoperative CRT and curative operation. Of these, 16 patients who were treated between August 2005 and June 2008 underwent LPLD on both sides (LPLD group). Sixteen patients who were treated between July 2008 and January 2013 underwent LPLD only on the side with suspected LPLN metastasis determined by pretreatment imaging; in cases without LPLN metastasis, only total mesorectal excision was performed (limited-LPLD group). The overall survival and relapse-free survival between the LPLD and the limited-LPLD groups were compared. Preoperative CRT was able to lower clinical lymph node status in 50% of the cases. In addition, pathological lymph node status did not exceed the pretreatment clinical lymph node status stage in the LPLD group. There were no differences in the overall survival and relapse-free survival between the two groups (P=0.729 and P=0.874, respectively). We conclude that multi-imaging studies have a very low risk of overlooking pathologically positive LPLN metastases. Therefore, limited LPLD is a feasible strategy for patients with advanced rectal cancer and suspicious LPLN metastases based on pretreatment imaging.


Annals of Thoracic and Cardiovascular Surgery | 2015

A Case of Benign Esophageal Schwannoma Causing Life-threatening Tracheal Obstruction

Ayako Tomono; Tetsu Nakamura; Yasunori Otowa; Tatsuya Imanishi; Yugo Tanaka; Yoshimasa Maniwa; Yoshihiro Kakeji

A 59-year-old woman presented with a 1-year history of dysphagia. She suffered from a large mediastinal mass obstructing trachea and bilateral main bronchus, which led to dyspnea and disturbed consciousness. Immediate intubation and surgery was required. A solid tumor that included esophagus and right vagal nerve, and adhered to the membranous part of the bronchus was found. However, the tumor could be resected en bloc and the patient has been free from recurrence. Pathologically, the tumor exhibited proliferative spindle cells and was diffusely positive for S-100 protein. It was therefore diagnosed as a benign esophageal schwannoma. To our knowledge, this is the first report of tracheal obstruction from a benign esophageal schwannoma, which we successfully treated with emergency subtotal esophagectomy.


European Journal of Gastroenterology & Hepatology | 2012

Eosinophilic gastroenteritis associated with multiple gastric cancer.

Yasunori Otowa; Masaaki Mitsutsuji; Takeshi Urade; Teruhiro Chono; Haruki Morimoto; Kunio Yokoyama; Kenro Hirata; Shiro Kawamura; Etsuji Shimada; Masayuki Fujita

Eosinophilic gastroenteritis (EG) is an inflammation of the digestive tract that is characterized by eosinophilic infiltration. There are no specific symptoms, and are related to the layer in which eosinophilic infiltration is observed. A 69-year-old Japanese man presented to our hospital with a history of general malaise, diarrhea, and dysgeusia. Esophagogastroduodenoscopy showed reddish elevated lesions that were edematous all over the gastric mucosa. In addition, three tumors were also observed. The biopsies of the reddish elevated mucosa revealed eosinophilic infiltration and tubular adenocarcinoma from the tumors. Colonoscopy showed abnormal reddish elevated mucosa. The biopsies from the reddish elevated mucosa showed eosinophilic infiltration. From the abdominal contrast computed tomography scan, tumor stain was seen in the anterior wall of the gastric body. No ascites, intestinal wall thickening, or lymph node swelling were found. A slight elevation in the serum immunoglobulin E (IgE), 480 IU/ml, was found from the laboratory test results; other laboratory results were within normal limits including the number of peripheral eosinophils. No specific allergen was found from the multiple antigen simultaneous test and from the skin patch test. The parasitic immunodiagnosis was negative. He was diagnosed with EG associated with gastric cancer and underwent total gastrectomy, regional lymph node dissection with reconstruction by a Roux-en-Y method. He was prescribed prednisolone after the operation and showed a good clinical response. There are many case reports on EG, but none of them were associated with cancer. We encountered a case of EG associated with multiple gastric cancer; the patient underwent total gastrectomy.


Endoscopy International Open | 2017

Safe management of laparoscopic endoscopic cooperative surgery for superficial non-ampullary duodenal epithelial tumors

Yasunori Otowa; Shingo Kanaji; Yoshinori Morita; Satoshi Suzuki; Masashi Yamamoto; Yoshiko Matsuda; Takeru Matsuda; Taro Oshikiri; Tetsu Nakamura; Fumiaki Kawara; Shinwa Tanaka; Tsukasa Ishida; Takashi Toyonaga; Takeshi Azuma; Yoshihiro Kakeji

Background and study aims  Endoscopic submucosal dissection (ESD) for duodenal tumors results in a high delayed perforation rate due to the thinness of the duodenal wall. In most cases with perforation after duodenal ESD, additional surgery is needed due to severe peritonitis. A newly developed procedure, laparoscopic endoscopic cooperative surgery for duodenal tumors (D-LECS), may help to avoid perforation after ESD. In our institution, patients with superficial non-ampullary duodenal epithelial tumors (SNADET) smaller than 50 mm which could not have en-bloc resection by endoscopic mucosal resection were treated with D-LECS. After a laparoscopic exposure of anterior duodenal wall of second portion, ESD was performed. Laparoscopic suturing from the serosal side of ESD site was performed for reinforcement. There were neither postoperative leakage nor other complications. Therefore, D-LECS can be performed safely and prevent perforation after ESD for SNADET. D-LECS could be selected as a treatment for SNADET which can be cured by ESD.


Scientific Reports | 2016

Flt1/VEGFR1 heterozygosity causes transient embryonic edema.

Yasunori Otowa; Kazumasa Moriwaki; Keigo Sano; Masanori Shirakabe; Shigenobu Yonemura; Masabumi Shibuya; Janet Rossant; Toshio Suda; Yoshihiro Kakeji; Masanori Hirashima

Vascular endothelial growth factor-A is a major player in vascular development and a potent vascular permeability factor under physiological and pathological conditions by binding to a decoy receptor Flt1 and its primary receptor Flk1. In this study, we show that Flt1 heterozygous (Flt1+/−) mouse embryos grow up to adult without life-threatening abnormalities but exhibit a transient embryonic edema around the nuchal and back regions, which is reminiscent of increased nuchal translucency in human fetuses. Vascular permeability is enhanced and an intricate infolding of the plasma membrane and huge vesicle-like structures are seen in Flt1+/− capillary endothelial cells. Flk1 tyrosine phosphorylation is elevated in Flt1+/− embryos, but Flk1 heterozygosity does not suppress embryonic edema caused by Flt1 heterozygosity. When Flt1 mutants are crossed with Aspp1−/− mice which exhibit a transient embryonic edema with delayed formation and dysfunction of lymphatic vessels, only 5.7% of Flt1+/−; Aspp1−/− mice survive, compared to expected ratio (25%). Our results demonstrate that Flt1 heterozygosity causes a transient embryonic edema and can be a risk factor for embryonic lethality in combination with other mutations causing non-lethal vascular phenotype.


Ejso | 2016

Safety and benefit of curative surgical resection for esophageal squamous cell cancer associated with multiple primary cancers

Yasunori Otowa; Tetsu Nakamura; Gosuke Takiguchi; Masashi Yamamoto; Shingo Kanaji; Tatsuya Imanishi; Taro Oshikiri; Satoshi Suzuki; Kenichi Tanaka; Yoshihiro Kakeji

BACKGROUND Enhancements in surgical techniques have led to improved outcomes for esophageal cancer. Recent findings have showed that esophageal cancer is frequently associated with multiple primary cancers, and surgical resection is usually complicated in such cases. The aim of this study was to clarify the clinical significance of surgery for patients with esophageal squamous cell cancer associated with multiple primary cancers. METHODS The clinical outcomes of surgical resection for esophageal cancer were compared among 79 patients with antecedent and/or synchronous cancers (Multiple cancer group) and 194 patients without antecedent and/or synchronous cancers (Single cancer group). RESULTS The most common site of multiple primary cancers was the pharynx (36 patients; 29.7%), followed by the stomach (24 patients; 19.8%). The reconstruction method was more complicated in the Multiple cancer group as a result of the prolonged surgery time and increased blood loss. However, postoperative morbidity and overall survival (OS) did not differ between the two groups. After esophagectomy, metachronous cancers were observed in 26 patients, with 30 regions in total, and 93.1% were found to be curable. Sex was the only independent risk factors for developing metachronous cancer after esophagectomy. CONCLUSIONS The presence of antecedent and synchronous cancers complicates the surgical resection of esophageal cancer; however, no differences were found in the OS and postoperative morbidity between the two groups. Therefore, surgical intervention should be selected as a first-line treatment. Because second primary cancers are often observed in esophageal cancer, we recommend a close follow-up using esophagogastroduodenoscopy and contrast-enhanced computed tomography.


Asian Journal of Endoscopic Surgery | 2018

Incarcerated obturator hernia treated using a hybrid laparoscopic and anterior preperitoneal approach: A case report

Yuta Yamazaki; Yasunori Otowa; Shunsuke Kusano; Koichi Nakajima; Shinsuke Satake; Yoshisada Yamasaki

Obturator hernia (OH) is a rare cause of bowel obstruction. Although several surgical approaches, including the laparoscopic approach, have been reported to date, a standard approach for treating OH has not been established. A 101‐year‐old woman who presented with constipation and vomiting was admitted to our hospital. CT revealed an incarcerated small bowel within the left obturator foramen, and a diagnosis of left‐sided incarcerated OH with small bowel ileus was made. With the patient under general anesthesia, exploratory laparoscopy was performed; we identified an OH with an incarcerated small bowel, which was judged viable after hernia reduction. We repaired the hernia using an anterior preperitoneal approach under laparoscopic assistance and placed a prosthetic mesh over the obturator foramen. The patient recovered with no postoperative complications and was discharged on postoperative day 4. A hybrid laparoscopic and anterior preperitoneal approach is safe and effective for treating an incarcerated OH in an elderly patient.


CRSLS: MIS Case Reports from SLS | 2014

Curable Resection in Gastric and Lymph Node Metastases From Melanoma

Yasunori Otowa; Satoshi Suzuki; Tatsuya Imanishi; Tetsu Nakamura; Kenichi Tanaka; Masanobu Sakaguchi; Toshinori Bito; Yoshihiro Kakeji

We herein report a rare case of gastric and regional lymph node metastasis of cutaneous malignant melanoma that underwent curative resection. The patient, a 68-year-old man, was first diagnosed as having cutaneous malignant melanoma of the right forearm in 2005. He had extensive skin excision and axillary lymph node dissection and had undergone adjuvant chemotherapy. Six years after the primary surgery, gastrointestinal endoscopy revealed gastric metastasis of a malignant melanoma. As there was no other metastasis found, laparoscopic-assisted distal gastrectomy with lymph node dissection was performed. Microscopic findings showed diffuse melanin granule growth invading the muscularis propria of the stomach. Micrometastases of the lymph nodes were observed that were not detected by preoperative examination. Seventeen months have passed without recurrence. We conclude that regional lymph node dissection should be performed with gastrectomy whenever distant metastases are not observed, because there is a possibility of micrometastases, which cannot be detected preoperatively.

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