Masaya Kawai
Juntendo University
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Publication
Featured researches published by Masaya Kawai.
Digestive Endoscopy | 2015
Yuichi Tomiki; Masaya Kawai; Kazuhiro Takehara; Yoshihiko Tashiro; Shinya Munakata; Kazumasa Kure; Shun Ishiyama; Kiichi Sugimoto; Hirohiko Kamiyama; Makoto Takahashi; Kazuhiro Sakamoto
Colorectal endoscopic submucosal dissection (ESD) is a useful treatment method; however, no index has been established for time for patient to start food ingestion or be discharged after ESD. We investigated the potential of a clinical pathway in which patients started food ingestion on day 2 after ESD and were discharged on day 3.
Oncology Letters | 2016
Masaya Kawai; Hiromitsu Komiyama; Masaki Hosoya; Haruna Okubo; Tomoaki Fujii; Norihiko Yokoyama; Chiyo Sato; Takae Ueyama; Atsushi Okuzawa; Michitoshi Goto; Yutaka Kojima; Makoto Takahashi; Kiichi Sugimoto; Shun Ishiyama; Shinya Munakata; Dai Ogura; Shin‑Ichiro Niwa; Yuichi Tomiki; Takumi Ochiai; Kazuhiro Sakamoto
Colorectal cancer is a prevalent malignancy worldwide, and investigations are required to elucidate the underlying carcinogenic mechanisms. Amongst these mechanisms, de novo carcinogenesis and the adenoma to carcinoma sequence, are the most understood. Metastasis of colorectal cancer to the liver often results in fatality, therefore, it is important for any associated risk factors to be identified. Regarding the treatment of the disease, it is important to manage not only the primary colorectal tumor, but also the liver metastases. Previously, through gene variation analysis, chromosomal loss has been indicated to serve an important role in liver metastasis. Such analysis may aid in the prediction of liver metastasis risk, alongside individual responses to treatment, thus improving the management of colorectal cancer. In the present study, we aimed to clarify a cause of the liver metastasis of colorectal cancer using comparative genomic hybridization analysis. A total of 116 frozen samples were analyzed from patients with advanced colorectal cancer that underwent surgery from 2004 to 2011. The present study analyzed mutations within tumor suppressor genes non-metastatic gene 23 (NM23), deleted in colorectal carcinoma (DCC) and deleted in pancreatic carcinoma, locus 4 (DPC4), which are located on chromosomes 17 and 18 and have all been reported to affect liver metastasis of colorectal cancer. The association between chromosomal abnormalities (duplication and deletion) and liver metastasis of colorectal cancer was evaluated using comparative genomic hybridization. Cluster analysis indicated that the group of patients lacking the long arm of chromosome 17 demonstrated the highest rate of liver metastasis. No significant association was observed between the frequency of liver metastases for synchronous and heterochronous colorectal cancer cases and gene variation (P=0.206). However, when these liver metastasis cases were divided into the synchronous and heterochronous types, the ratio of each was significantly different between gene variation groups, classified by the existence of the 17q deletion (P=0.023). These results indicate that the deletion of 17q may act as a predictive marker of liver metastasis in postoperative states.
Case Reports in Gastroenterology | 2014
Yoshihiko Tashiro; Masaya Kawai; Kazuhiro Takehara; Shinya Munakata; Shun Ishiyama; Kiichi Sugimoto; Makoto Takahashi; Yutaka Kojima; Michitoshi Goto; Yuichi Tomiki; Tomoyoshi Shibuya; Taro Osada; Sumio Watanabe; Kazuhiro Sakamoto
Capsule endoscopy (CE) is commonly used for examining and diagnosing gastrointestinal disease, especially small bowel disease. Capsule retention is a well-known and significant complication of CE and requires surgical or endoscopic removal. Most reports described the retrieval of retained CE via laparotomy. We report a case of successful retrieval of the capsule using single incision laparoscopic surgery.
Case Reports in Gastroenterology | 2015
Kazumasa Kure; Masaya Kawai; Shun Ishiyama; Hirohiko Kamiyama; Yuichi Tomiki; Kazuhiro Sakamoto; Atsushi Arakawa; Takashi Yao
An 81-year-old female consulted a local physician due to diarrhea. Since general fatigue and body weight loss were observed, she was admitted for detailed examination and treatment. Colonoscopy revealed a circumferential giant tumor with a maximum diameter of 10 cm in the rectum, and biopsy findings indicated villous adenoma. The tumor secreted a large amount of mucus, and a diagnosis of electrolyte depletion syndrome causing electrolyte disorders was made. We performed endoscopic submucosal dissection (ESD) as a less invasive procedure. The tumor was so big that the procedure had to be completed in two separate steps and it took 1,381 min in total. The tumor was histologically diagnosed as well-differentiated adenocarcinoma in high-grade adenoma located in the lower to upper rectum, invading into the mucosa without lymphatic or venous invasion. The stump of the resected specimen was negative for adenocarcinoma, however the horizontal stump was positive for adenoma. We administered steroid suppositories to prevent stenosis. After ESD, general fatigue and diarrhea disappeared and electrolyte disorders resolved. The patient had good clinical outcome without recurrence or stenosis.
Case Reports in Gastroenterology | 2013
Kiichi Sugimoto; Masaya Kawai; Kazuhiro Takehara; Yoshihiko Tashiro; Shinya Munakata; Shun Ishiyama; Hiromitsu Komiyama; Makoto Takahashi; Yutaka Kojima; Michitoshi Goto; Yuichi Tomiki; Kazuhiro Sakamoto; Seiji Kawasaki
The patient was a 68-year-old man who was admitted to our hospital with a liver tumor. Abdominal ultrasonography and computed tomography revealed a liver tumor 30 mm in diameter. On colonoscopy, a pedunculated tumor with a central depression (20 mm in diameter) was observed in the ascending colon, and this tumor was considered to be invading deeply into the submucosal layer. Right hemicolectomy with D3 lymphadenectomy and partial hepatectomy were performed simultaneously. On histopathological examination of the resected specimen, the tumor was a well-differentiated tubular adenocarcinoma with 3,000 μm invasion of the submucosal layer. The liver tumor showed histological findings similar to those of the primary colorectal carcinoma. The pathological stage according to the 7th edition of the TNM classification was stage IV (T1N0M1). Nine months after the operation, computed tomography revealed hepatic hilar lymph node metastases and a great deal of ascites. The patient ultimately died 14 months after the operation.
Open Journal of Gastroenterology | 2018
Shinya Munakata; Kazuhiro Sakamoto; Kumpei Honjo; Masaya Kawai; Kiichi Sugimoto; Masakazu Ouchi; Makoto Takahashi; Yutaka Kojima; Kunihiko Nagakari; Yuichi Tomiki
Objectives: To investigate the epidemiology and risk factors of chylous ascites. Methods: We identified the cases of 913 consecutive patients who underwenturgery for colorectal cancerat our University Hospital between January 2005and December2016. We divided the patients into thosewith and those without chylous ascites and compared the two groups by age, gender, body mass index, tumor location, T, N factor, stage, operation time, intra-operative bleeding, and duration of postoperative hospital stay. Results: Chylous ascites developed in 8 of the 913 patients (0.8%). Neither age, sex, tumor location, and body mass indexnor number of lymph nodeswereassociated with postoperative chylous ascites. Ascites occurred significantly less frequently in the early stage of colorectal cancer than in the late stage (p = 0.04). There was no significant difference between the groups in operative factors, including operation time and blood loss. Postoperative hospital stays were longer in patients with chylous ascites (20.5 days) than in those without (11 days) (p = 0.02). Conclusions: Late stage was one of the risk factors for chylous ascites in the present study. Other risks, such as tumor location and blood loss,will vary from institution to institution.
Open Journal of Gastroenterology | 2018
Shinya Munakata; Kiichi Sugimoto; Kumpei Honjo; Masaya Kawai; Shingo Kawano; Hirohiko Kamiyama; Masakazu Ouchi; Makoto Takahashi; Yuichi Tomiki; Kazuhiro Sakamoto
Objectives: Our aim is investigating the predictive potential of these available and convenient laboratory dates in stage IV colorectal cancer (CRC) patients. Methods: We identified the cases of 114 consecutive patients who underwent the surgery at our Hospital between January 2006 and December 2012 by using the multivariate analysis, the Cox proportional-hazard regression model. Results: Multivariate analysis for the predictors of survival showed metastatic lesion resection [hazard ratio (HR) = 3.2, 95% confidence interval (CI) 1.6 - 6.6; p = 0.007] and only primary lesion resection (HR = 1.9, 95% CI 1.1 - 4.0; p = 0.045) remained independently significant prognostic factors. Therefore, we divided in 3 groups, 1) metastatic lesion resection group with primary lesion resection (n = 52 in the Met/Prim lesion group), 2) primary lesion resection without metastatic lesion resection (n = 38 in the Primary lesion group) and 3) palliative operation (n = 24 in the Palliative group). Age was the only independent risk factor in the Met/Prim lesion group. In the Primary lesion group, Neutrophil lymphocyte ratio (NLR) > 5, elevated Alanine aminotransferase and patients without chemotherapy were correlated with poor survival. In the Palliative group, NLR > 5 and patients who could not be treated with chemotherapy remained independent predictors of worse survival. Conclusions: NLR is not only simple and convenient for classification of patients, but also one of the important predictors of mortality for stage IV incurable CRC patients.
Journal of Minimal Access Surgery | 2018
Rina Takahashi; Kazuhiro Sakamoto; Hisashi Ro; Kazumasa Kure; Masaya Kawai; Shun Ishiyama; Kiichi Sugimoto; Yutaka Kojima; Atsushi Okuzawa; Yuichi Tomiki
A 76-year-old male underwent endoscopic mucosal resection for a stage T1 tumour of the sigmoid colon. We performed laparoscopic sigmoidectomy through 5 ports using needlescopic instruments. The resected specimen was extracted from the abdominal cavity transanally. After attaching an anvil to the sigmoidal stump, the rectal stump was reclosed using an endoscopic linear stapler, and then, colorectal anastomosis was conducted using the double stapling technique. Performing transanal specimen extraction using needlescopic forceps improves aesthetic outcomes and reduces post-operative pain and the risk of abdominal incisional hernias. This method is an easy to introduce a form of reduced-port surgery because of its feasibility and conventional port arrangement. Hence, we consider that it is an option for minimally invasive surgery.
Case Reports in Surgery | 2018
Ikuo Watanobe; Hiroko Kida; Yuuki Sekine; Masaya Kawai; Shozo Miyano; Michio Machida; Toshiaki Kitabatake; Hiroyuki Sugo; Yoshifumi Lee; Kuniaki Kojima
Congenital epidermolysis bullosa is a rare, genetic condition in which even slight stimulation can cause blistering of the skin or mucosa. While previous reports of treatments requiring general anesthesia in these patients were focused on anesthesia-related procedures, such as endotracheal intubation, no report has described specific management required for these patients during surgery, such as preparation of the surgical site, fixation of infusion lines and other tubes, and adjustment of the operation table. This is probably the first report to address these issues. This report presents a case of recessive dystrophic congenital epidermolysis bullosa in which open hepatectomy was safely performed.
Case Reports in Gastroenterology | 2017
Kazuhiro Takehara; Kazuhiro Sakamoto; Rina Takahashi; Masaya Kawai; Shingo Kawano; Shinya Munakata; Kiichi Sugimoto; Makoto Takahashi; Yutaka Kojima; Tetsu Fukunaga; Yoshiaki Kajiyama; Seiji Kawasaki
Superior mesenteric artery syndrome (SMAS) is a relatively rare disease that involves bowel obstruction symptoms, such as vomiting and gastric distension, owing to the compression of the third portion of the duodenum from the front by the superior mesenteric artery (SMA) and from the rear by the abdominal aorta and the spine. SMAS is diagnosed on the basis of an upper gastrointestinal examination series indicating the obstruction of the third portion of the duodenum or a computed tomography scan indicating the narrowing of the branch angle between the aorta and the SMA (i.e., the aorta-SMA angle). Here, we report the case of a 78-year-old woman diagnosed with SMAS after a laparoscopic right hemicolectomy for cecal cancer, whose condition was improved by enteral nutritional therapy. We used her controlling nutritional status (CONUT) score as a nutrition assessment and noted the changes in the aorta-SMA angle over the course of the disease. This patient appeared to develop SMAS, on the basis of a worsened CONUT score and a decreased aorta-SMA angle, owing to the inflammation resulting from the intraoperative dissection of the tissues around the SMA and prolonged postoperative fasting. After the initiation of enteral nutritional therapy, the patient exhibited body weight gain and an improved aorta-SMA angle and CONUT score. Hence, assessment of the aorta-SMA angle and CONUT score is an important preoperative consideration.