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Dive into the research topics where Kenta Nakahara is active.

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Featured researches published by Kenta Nakahara.


World Journal of Surgical Oncology | 2015

Transverse colon cancer occurring at a colostomy site 35 years after colostomy: a case report.

Chiyo Maeda; Eiji Hidaka; Mari Shimada; Shoji Shimada; Kenta Nakahara; Daisuke Takayanagi; Yusuke Takehara; Shumpei Mukai; Naruhiko Sawada; Fumio Ishida; Shin-ei Kudo

BackgroundCarcinomas occurring at colostomy sites are rare, and most of these are metachronous colorectal cancers. The median time between colostomy and development of a carcinoma at a colostomy site is 22 years, which exceeds the length of the recommended follow-up period. We report a rare case of a carcinoma of the transverse colon occurring at a colostomy site in a patient without a history of colorectal cancer.Case reportAn 89-year-old woman presented with a tumor occurring at a colostomy site. Thirty-five years previously, she had undergone a transverse loop colostomy for an iatrogenic colon perforation that occurred during left ureteral lithotomy. Upon physical examination, the patient had a hard nodule measuring 3 cm at the colostomy site. A biopsy of the nodule suggested adenocarcinoma, and the preoperative diagnosis was transverse colon cancer. A laparotomy was performed via a peristomal incision with 5-mm skin margins, and the tumor was covered by a surgical glove to avoid any tumor seeding. The colon was separated from the tumor by 5-cm margins, and the specimen was removed en bloc. An end colostomy was constructed to a new site on the right side of the abdomen. The deficit in the abdominal wall was repaired, and the skin was closed via a purse-string suture. The final diagnosis of the stoma tumor was transverse colon cancer (T2, N0, M0, stage I). One year and five months after surgery, there was no evidence of recurrence.ConclusionsThe occurrence of carcinomas at colostomy sites in patients without a history of colorectal cancer is rare. It is important to train ostomates to monitor the stoma for possible tumor recurrence.


Digestive Surgery | 2017

Fecal Volume after Laparoscopic Low Anterior Resection Predicts Anastomotic Leakage

Eiji Hidaka; Chiyo Maeda; Kenta Nakahara; Shoji Shimada; Shumpei Mukai; Naruhiko Sawada; Fumio Ishida; Shin-ei Kudo

Background/Aim: Anastomotic leakage (AL) is a major complication after laparoscopic low anterior resection (Lap-LAR). Many surgeons encounter AL following severe postoperative diarrhea. However, little is known about the relationship between postoperative fecal volume and AL. This study determined whether postoperative fecal volume can predict AL. Methods: A retrospective assessment was performed with data from 176 patients with rectal cancers who underwent Lap-LAR between April 2011 and August 2015. A transanal tube was routinely placed in all cases. The fecal volume from the transanal tube was measured daily. The total fecal volume for 3 days after surgery was compared between the AL and non-AL groups. Results: AL occurred in 11 patients. There were 3 patients with a fecal volume ≥1,000 mL for 3 days after surgery. AL occurred in these 3 patients. In patients with a fecal volume <1,000 mL, the total fecal volume was significantly greater in the AL group than that in the non-AL group (p = 0.0003). The cut-off value of the total fecal volume in AL was 118 mL. Conclusions: The volume of fecal discharge for 3 days after surgery is associated with the incidence of AL, and a fecal volume ≥118 mL may be a reliable predictor for AL.


Case Reports in Surgery | 2016

Laparoscopic Extirpation of a Schwannoma in the Lateral Pelvic Space

Eiji Hidaka; Yasuhiro Ishiyama; Chiyo Maeda; Kenta Nakahara; Shoji Shimada; Shumpei Mukai; Naruhiko Sawada; Fumio Ishida; Shin-ei Kudo

Schwannomas in the lateral pelvic space are very rare. Here, we report the case of a 48-year-old woman who had a tumor detected in her abdomen by abdominal ultrasonography. Abdominal computed tomography and magnetic resonance imaging revealed a well-defined solid tumor of 65 mm in diameter in the right lateral pelvic space. We performed laparoscopic surgery under a diagnosis of a gastrointestinal tumor or neurogenic tumor. The tumor was safely dissected and freed from the surrounding tissues using sharp and blunt maneuvers. The tumor originated from the right sciatic nerve. Complete laparoscopic extirpation was performed with preservation of the right sciatic nerve. Pathological examination suggested schwannoma. The patient recovered well but had remaining sciatic nerve palsy in her right foot. Laparoscopic extirpation for a schwannoma in the lateral pelvic space was safe and feasible due to the magnified surgical field afforded by laparoscopy.


Oncogene | 2018

The impact of stromal Hic-5 on the tumorigenesis of colorectal cancer through lysyl oxidase induction and stromal remodeling

Tomokatsu Omoto; Joo-ri Kim-Kaneyama; Xiao-Feng Lei; Akira Orimo; Koji Ohnishi; Kosuke Yoshihara; Aya Miyauchi; Shuo Li; Lin Gao; Takahiro Umemoto; Junichi Tanaka; Kenta Nakahara; Motohiro Takeya; Fumio Ishida; Shin-ei Kudo; Shogo Haraguchi; Takuro Miyazaki; Akira Miyazaki

Carcinoma-associated fibroblasts (CAFs) influence tumor initiation, progression, and metastasis within the tumor-associated stroma. This suggests that CAFs would be a potential target for tumor therapy. Here we found that Hydrogen peroxide-inducible clone-5 (Hic-5), also named transforming growth factor beta-1-induced transcript 1 protein (Tgfb1i1), was strongly induced in CAFs found in human colorectal cancer. To investigate the role of Hic-5 in CAFs, we isolated CAFs and the control counterpart normal fibroblasts (NFs) from human colorectal cancer and non-cancerous regions, respectively. Hic-5 was highly expressed in isolated human CAFs and strongly induced in NFs in culture by the supernatant from cultured colorectal cancer cells as well as cytokines such as TGF-β, IL-1β and stromal cell-derived factor 1 (SDF-1/CXCL12). Furthermore, tumor growth was inhibited in a co-culture assay with Hic-5 knockdown fibroblasts compared with control fibroblasts. To clarify the function and significance of Hic-5 in colorectal cancer in vivo, we utilized a mouse model of azoxymethane (AOM)-induced colorectal cancer using Hic-5-deficient mice. Lack of Hic-5 in CAFs completely prevented AOM-induced colorectal cancer development in the colon tissues of mice. Mechanistic investigation revealed that Hic-5 promoted the expression of lysyl oxidase and collagen I in human control counterpart fibroblasts. Taken together, these results demonstrate that Hic-5 in CAFs is responsible for orchestrating or generating a tumor-promoting stroma.


Asian Journal of Endoscopic Surgery | 2016

Spontaneously ruptured hepatic cyst treated with laparoscopic deroofing and cystobiliary communication closure: A case report

Shoji Shimada; Yoshiaki Hara; Naoto Wada; Kenta Nakahara; Daisuke Takayanagi; Yasuhiro Ishiyama; Chiyo Maeda; Shunpei Mukai; Naruhiko Sawada; Noriko Yamaguchi; Yoshinobu Sato; Eiji Hidaka; Fumio Ishida; Shin-ei Kudo

The rupture of a nonparasitic hepatic cyst with biliary communication is rare. We report the case of a patient with a hepatic cyst with biliary communication that spontaneously ruptured and was successfully treated by laparoscopic deroofing and closure of the communication. A 61‐year‐old woman presented at our hospital with a chief complaint of right upper abdominal pain. Enhanced abdominal CT showed a collapsed hepatic cyst and fluid collection. Drip infusion CT cholangiography showed contrast medium pooling in the collapsed cyst. Therefore, hepatic cyst rupture with biliary communication was diagnosed, and laparoscopic deroofing and closure of the communication were performed. The postoperative course was uneventful, and the patient was discharged on postoperative day 6. In cases of hepatic cyst rupture, even in the presence of biliary communication, laparoscopic deroofing and closure of the communication should be recommended as the first‐choice treatment.


Asian Journal of Endoscopic Surgery | 2015

Laparoscopic surgery for sigmoidocutaneous fistula due to diverticulitis: A case report.

Eiji Hidaka; Kenta Nakahara; Chiyo Maeda; Yusuke Takehara; Fumio Ishida; Shin-ei Kudo

Sigmoidocutaneous fistulas due to sigmoid colon diverticulitis are very rare. Here we report a case in which laparoscopic sigmoidectomy was used to successfully treat a sigmoidocutaneous fistula due to diverticulitis. A 41‐year‐old man was admitted to our hospital because of redness and swelling of the left inguinal skin. Enhanced abdominal CT revealed a subcutaneous abscess in the left lower abdomen. Percutaneous drainage was performed, and fistulography revealed a fistula between the sigmoid colon and left inguinal skin. Therefore, a sigmoidocutaneous fistula was diagnosed, and laparoscopic sigmoidectomy and fistulectomy were performed. The sigmoid colon had several diverticula, and a pathological examination revealed that the sigmoidocutaneous fistula was due to diverticulitis. The postoperative course was uneventful, and the patient was discharged on postoperative day 8. In cases of sigmoidocutaneous fistula, laparoscopic treatment can be safely performed.


Surgical Endoscopy and Other Interventional Techniques | 2015

Efficacy of transanal tube for prevention of anastomotic leakage following laparoscopic low anterior resection for rectal cancers: a retrospective cohort study in a single institution

Eiji Hidaka; Fumio Ishida; Shumpei Mukai; Kenta Nakahara; Daisuke Takayanagi; Chiyo Maeda; Yusuke Takehara; Junichi Tanaka; Shin-ei Kudo


Surgical Endoscopy and Other Interventional Techniques | 2014

Evaluation of the safety and efficacy of esophagojejunostomy after totally laparoscopic total gastrectomy using a trans-orally inserted anvil: a single-center comparative study

Hiroaki Ito; Haruhiro Inoue; Noriko Odaka; Hitoshi Satodate; Manabu Onimaru; Haruo Ikeda; Daisuke Takayanagi; Kenta Nakahara; Shin-ei Kudo


Surgical Endoscopy and Other Interventional Techniques | 2018

Impact of obesity on short- and long-term outcomes of laparoscopy assisted distal gastrectomy for gastric cancer

Shoji Shimada; Naruhiko Sawada; Yasuhiro Ishiyama; Kenta Nakahara; Chiyo Maeda; Shumpei Mukai; Eiji Hidaka; Fumio Ishida; Sin-ei Kudo


World Journal of Surgical Oncology | 2014

Malignant peritoneal mesothelioma with lymph node metastasis that originated in the transverse colon

Yusuke Takehara; Shungo Endo; Yuichi Mori; Kenta Nakahara; Daisuke Takayanagi; Shoji Shimada; Tomokatsu Omoto; Chiyo Maeda; Shumpei Mukai; Eiji Hidaka; Fumio Ishida; Junichi Tanaka; Shin-ei Kudo

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