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Featured researches published by Ryuichi Kawahara.


Journal of the Pancreas | 2012

Metastatic Pulmonary Adenocarcinoma 13 Years After Curative Resection for Pancreatic Cancer: Report of a Case and Review of Japanese Literature

Yuhei Kitasato; Masamichi Nakayama; Gen Akasu; Munehiro Yoshitomi; Kazuhiro Mikagi; Yuichiro Maruyama; Ryuichi Kawahara; Hiroto Ishikawa; Toru Hisaka; Masafumi Yasunaga; Hiroyuki Horiuchi; Naoyuki Saito; Shinzo Takamori; Yoshinobu Okabe; Masayoshi Kage; Hisafumi Kinoshita; Hiroyuki Tanaka

CONTEXT For the majority of patients, ductal adenocarcinoma of the pancreas remains a lethal disease. Currently, surgical extirpation for localized disease offers the only chance for long-term survival. CASE REPORT We report a patient who underwent successful resection of isolated lung metastasis occurring 13 years after pancreatic cancer resection. A 59-year-old woman underwent distal pancreatectomy for pancreatic cancer 13 years previously, followed by adjuvant chemotherapy, and was followed-up at the outpatient clinic of a local hospital. From around June 2010, she noticed bloody sputum, so she visited a local hospital. Since her chest X-ray and CT revealed a 1.5 cm mass shadow in the segment 10 of her right lung and she was referred to the Respiratory Disease Center of our hospital. As a result of through examinations, she was strongly suspected of having lung metastasis of pancreatic cancer, and underwent partial pneumonectomy. Postoperative histopathological examination of the resected specimen was consistent with lung metastasis of pancreatic cancer. She is still alive and currently receives third line of chemotherapy. CONCLUSION Patients who have achieved long-term survival after pancreatic cancer resection and can tolerate surgery may benefit from resection of a lung metastasis of pancreatic cancer in terms of survival, if it controls the metastasis.


Oncology Reports | 2013

Potential usefulness of mucin immunohistochemical staining of preoperative pancreatic biopsy or juice cytology specimens in the determination of treatment strategies for intraductal papillary mucinous neoplasm

Toru Hisaka; Hiroyuki Horiuchi; Shinji Uchida; Hiroto Ishikawa; Ryuichi Kawahara; Yusuke Kawashima; Masanori Akashi; Kazuhiro Mikagi; Yusuke Ishida; Yoshinobu Okabe; Masamichi Nakayama; Yoshiki Naito; Hirohisa Yano; Tomoki Taira; Akihiko Kawahara; Masayoshi Kage; Hisafumi Kinoshita; Kazuo Shirozu

We classified resected intraductal papillary mucinous neoplasms (IPMNs) into four subtypes (gastric, intestinal, pancreatobiliary and oncocytic) according to their morphological features and mucin expression, determined their clinicopathological characteristics and investigated the possibility of preoperatively diagnosing these subtypes. Sixty resected tumors, 4 preoperative tumor biopsies and 10 preoperative pancreatic juice cytology specimens were analyzed. The gastric and intestinal types accounted for the majority of IPMNs. Non-gastric type IPMNs were of high-grade malignancy. Many of the pancreatobiliary-type IPMNs were in an advanced stage and were associated with a poor prognosis. The results of mucin immunohistochemical staining of preoperative biopsy and surgically resected specimens were in agreement with each other, and in close agreement with those for pancreatic juice cytology specimens obtained from 10 patients during endoscopic retrograde cholangiopancreatography (ERCP). The immunostaining of preoperative biopsy specimens and ERCP-obtained pancreatic juice cytology specimens may be useful in the differential diagnosis of gastric and intestinal types of IPMN. If such techniques enable the preoperative diagnosis of IPMN subtypes, their use in combination with conventional preoperative imaging modalities may lead to surgical treatment best suited for the biological characteristics of the four subtypes.


World Journal of Gastroenterology | 2014

Evaluation of endoscopic biliary stenting for obstructive jaundice caused by hepatocellular carcinoma.

Gen Sugiyama; Yoshinobu Okabe; Yusuke Ishida; Fumihiko Saitou; Ryuichi Kawahara; Hiroto Ishikawa; Hiroyuki Horiuchi; Hisafumi Kinoshita; Osamu Tsuruta; Michio Sata

AIM To review the usefulness of endoscopic biliary stenting for obstructive jaundice caused by hepatocellular carcinoma and identify problems that may need to be addressed. METHODS The study population consisted of 36 patients with obstructive jaundice caused by hepatocellular carcinoma (HCC) who underwent endoscopic biliary stenting (EBS) as the initial drainage procedure at our hospital. The EBS technical success rate and drainage success rate were assessed. Drainage was considered effective when the serum total bilirubin level decreased by 50% or more following the procedure compared to the pre-drainage value. Survival time after the procedure and patient background characteristics were assessed comparatively between the successful drainage group (group A) and the non-successful drainage group (group B). The EBS stent patency duration in the successful drainage group (group A) was also assessed. RESULTS The technical success rate was 100% for both the initial endoscopic nasobiliary drainage and EBS in all patients. Single stenting was placed in 21 patients and multiple stenting in the remaining 15 patients. The drainage successful rate was 75% and the median interval to successful drainage was 40 d (2-295 d). The median survival time was 150 d in group A and 22 d in group B, with the difference between the two groups being statistically significant (P < 0.0001). There were no statistically significant differences between the two groups with respect to patient background characteristics, background liver condition, or tumor factors; on the other hand, the two groups showed statistically significant differences in patients without a history of hepatectomy (P = 0.009) and those that received multiple stenting (P = 0.036). The median duration of stent patency was 43 d in group A (2-757 d). No early complications related to the EBS technique were encountered. Late complications occurred in 13 patients (36.1%), including stent occlusion in 7, infection in 3, and distal migration in 3. CONCLUSION EBS is recommended as the initial drainage procedure for obstructive jaundice caused by HCC, as it appears to contribute to prolongation of survival time.


Surgery Today | 2010

Perioperative challenges associated with a pancreaticoduodenectomy and distal pancreatectomy for pancreatic cancer in patients with situs inversus totalis: Report of two cases

Yuichiro Maruyama; Hiroyuki Horiuchi; Yoshinobu Okabe; Ryuichi Kawahara; Shinji Uchida; Takenori Sakai; Toru Hisaka; Hiroto Ishikawa; Kazuhiro Mikagi; Munehiro Yoshitomi; Yusuke Kawashima; Manami Fujishita; Gen Akasu; Mitsuru Katsumoto; Daimei Eto; Mitsutoshi Ureshino; Yuichi Goto; Hiroki Ureshino; Hisafumi Kinoshita

Situs inversus totalis is a rare anatomic variant of a complete mirror-image transposition of the thoracic and abdominal viscera. The performance of a pancreaticoduodenectomy and distal pancreatectomy in patients with situs inversus totalis is both rare and challenging. We herein present two cases of pancreatic cancer with situs inversus totalis. The abdominal anatomy was preoperatively assessed by multidetectorrow computed tomography, three-dimensional reconstruction, and angiography. We herein report that a pancreaticoduodenectomy and distal pancreatectomy with standard regional lymphadenectomy are feasible in patients with situs inversus totalis. Due to the transposition of the viscera and major blood vessels in such cases, preoperative knowledge of the exact anatomy, mapping of anomalies, and meticulous forward planning are essential for performing these technically difficult and complex hepatobiliary-pancreatic surgeries.


Transplantation Proceedings | 2018

Endovascular Treatment for Very Early Hepatic Artery Stenosis Following Living-Donor Liver Transplantation: Report of Two Cases

Yuichi Goto; Nobuhisa Shirahama; S. Sasaki; Ryuichi Kawahara; Hisamune Sakai; Hiroto Ishikawa; Toru Hisaka; T. Ogata; Masafumi Yasunaga; Yoshito Akagi; Hiroyuki Tanaka; Koji Okuda

BACKGROUND Some literature has reported on endovascular treatment for very early hepatic artery stenosis (HAS; within 2 weeks after liver transplantation, and has deemed endovascular treatment to be a contraindication because out of serious complications associated with the procedure. We report on 2 cases of very early HAS successfully treated with endovascular treatment after living-donor liver transplantation (LDLT). CASE 1: A 54-year-old woman underwent LDLT with a left liver graft. The native right gastric artery and left hepatic artery (LHA) of the donor were anastomosed. On postoperative day (POD) 13, HAS was suspected and multidetector computerized tomographic angiography (MDCTA) was performed, which revealed 90% stenosis of the arterial anastomosis and 50% stenosis of the LHA in the graft. We performed percutaneous balloon arterioplasty (PBA) without any complications. The artery was patent with a postoperative follow-up of 60 months without the need for repeat intervention. CASE 2: A 67-year-old woman with a history of repeated transarterial chemoembolization for hepatocellular carcinoma underwent LDLT with a left liver graft. The native A4 and LHA of the donor were anastomosed. We performed MDCTA on POD 11, which revealed 70% stenosis of the native hepatic artery. We performed PBA followed by stent placement on POD 11 without complication. The artery was patent with a postoperative follow-up of 40 months without the need for repeated intervention. CONCLUSIONS Endovascular treatment has the potential to avoid the need for repeated surgical interventions or retransplantation, and it can be safely performed in carefully selected patients.


The Kurume Medical Journal | 2016

Evaluation of Surgical Procedures for T2 Gallbladder Cancer in Terms of Recurrence and Prognosis

Ryuichi Kawahara; Takahisa Shirahama; Shyoichirou Arai; Daisuke Muroya; Yoriko Nomura; Shogo Fukutomi; Nobuhisa Shirahama; Katsuaki Takagi; Yuichi Goto; Masanori Akashi; Yuichirou Maruyama; Hisamune Sakai; Hiroto Ishikawa; Toru Hisaka; Masafumi Yasunaga; Hiroyuki Horiuchi; Koji Okuda; Yoshito Akagi; Hiroyuki Tanaka

T2 (tumor invades perimuscular connective tissue; no extension beyond serosa or into liver) gallbladder cancer has generally been treated by S4aS5 subsegmentectomy (S4aS5 HR). We investigated the therapeutic effect of full-thickness cholecystectomy (FC) and gallbladder bed resection (GBR), in terms of tumor location and resection margin (distance from the tumor). At our department we employ the following protocol to determine the extent of resection needed to achieve R0 status: (1) A tumor located in the gallbladder fundus (Gf) or body (Gb) and only on the free peritoneal side was classified as P-type, for which full-thickness cholecystectomy and regional lymph node dissection were performed. (2) A tumor located in Gf or Gb and in contact with the liver bed was classified as H-type, for which gallbladder bed resection and regional lymph node dissection were performed. (3) A tumor located in the gallbladder neck (Gn) was classified as N-type, for which gallbladder bed resection, bile duct resection, and regional lymph node dissection were performed. Twenty-two patients admitted to our department between January 2000 and December 2014 with pT2gallbladder cancers were included in our study. Surgical procedures performed were compared with those specified in our protocol, and patients in whom the extent of resection was greater than that specified in our strategy were evaluated clinicopathologically and in terms of recurrence and the prognosis. Six (27.2%), 7 (31.8%), and 9 (40.9%) patients underwent limited, standard, and extended surgery, respectively. Ten (66.7%) of 15 patients with tumors close to the liver bed underwent cholecystectomy or extended surgery, 7 (85.7%) of 8 patients with tumors close to the bile duct underwent bile duct resection, and 16 (72.7%) of 22 patients underwent regional lymph node dissection. Recurrence at the bile duct resection margin, para-aortic lymph node metastasis, and hepatic metastasis occurred in 2, 1, and 3 patients, respectively. The 3-year survival rates (for patients including those dying of noncancer causes) were 50, 100, and 75% after limited, standard, and extended surgery, respectively. There was a significant difference in the survival rate of patients who underwent standard or extended surgery (P=0.0273). Favorable results were obtained in T2 gallbladder cancer patients without performing S4aS5 subsegmentectomy. Depending on the tumor location, neither full-thickness cholecystectomy nor gallbladder bed resection appeared to pose problems regarding recurrence or prognosis. In conclusion, surgical treatment based on our protocol, which aims to achieve the condition of R0, may result in a sufficient therapeutic effect.


Jpn J Gastroenterol Surg, Nihon Shokaki Geka Gakkai zasshi | 2008

A Resected Case of Carcinoma of the Papilla of Vater Associated with Abnormality of the Bile Duct from the Caudate Lobe

Ryuichi Kawahara; Takenori Sakai; Satoshi Furukawa; Hiroto Ishikawa; Hisafumi Kinoshita; Shigeaki Aoyagi

肝外胆管走行異常は術中胆管損傷の原因として注意が必要である. 左右肝管合流部の位置より十二指腸乳頭側に位置する低位合流尾状葉胆管枝を伴う十二指腸乳頭部癌の1切除例を経験したので報告する. 症例は64歳の男性で, 黄疸にて近医受診CT, 上部消化管内視鏡検査にて乳頭部癌と診断され, 手術目的に当院入院となった. 入院時胆道造影検査にて, 総胆管より左肝管近傍へ流入する分枝を認め低位合流尾状葉胆管枝と診断. 手術は膵頭十二指腸切除を施行した. 手術所見は総胆管の左側より肝内に伸びる径2mmの尾状葉枝を認めた. 術後のCTでも尾状葉枝の拡張認めず退院となった. 異所肝管は術中損傷の原因の一つとして重要である. 2重支配を持たない異所肝管は結紮してはならないという報告や, 径2mm以上の胆管は再建の必要があると報告されている. 術前画像の詳細な検討とともに, 低位合流尾状葉胆管枝の存在にも注意が必要と考えられた.


The Kurume Medical Journal | 2011

Effect of Preoperative Immunonutrition in Patients Undergoing Hepatectomy; A Randomized Controlled Trial

Kazuhiro Mikagi; Ryuichi Kawahara; Hisafumi Kinoshita; Shigeaki Aoyagi


Journal of Hepato-biliary-pancreatic Surgery | 2007

Analysis of hTERT mRNA expression in biliary tract and pancreatic cancer.

Ryuichi Kawahara; Masaharu Odo; Hisafumi Kinoshita; Shigeaki Aoyagi


The Kurume Medical Journal | 2006

Endoscopic Ultrasonography-Guided Cystogastrostomy for Large Pancreatic Pseudocyst with Obstructive Jaundice-A Case Report-

Yoshinobu Okabe; Osamu Tsuruta; Yuki Wada; Kazuhiko Wada; Hideya Suga; Maisa Kudoh; Ryuichi Kawahara; Takatoshi Kodama; Hisafumi Kinoshita; Atsushi Toyonaga; Michio Sata

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Hiroto Ishikawa

University of South Florida

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