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Dive into the research topics where Masakuni Fujii is active.

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Featured researches published by Masakuni Fujii.


Transplant International | 2009

Long-term outcomes of endoscopic management for biliary strictures after living donor liver transplantation with duct-to-duct reconstruction

Hironari Kato; Hirofumi Kawamoto; Koichiro Tsutsumi; Ryo Harada; Masakuni Fujii; Ken Hirao; Naoko Kurihara; Osamu Mizuno; Etsuji Ishida; Tsuneyoshi Ogawa; Hirotoshi Fukatsu; Kazuhide Yamamoto; Takahito Yagi

Biliary strictures after living donor liver transplantation (LDLT) with duct‐to‐duct (D‐D) reconstruction are associated with postoperative morbidity and mortality. The aims of this study were to evaluate the long‐term outcomes of endoscopic deployment of plastic stents, and to investigate factors associated with the stent deployment failure. Between April 2001 and May 2007, 96 patients received LDLT with D‐D reconstruction at Okayama University Hospital. Among them, 41 patients (43%) had anastomotic biliary strictures, and all were referred first for endoscopic retrograde cholangiography (ERC). When deployment was unsuccessful, a percutaneous transhepatic procedure was employed. Successful stent deployment was achieved in 35 out of total 41 patients (85%) by both procedures. Among the 35 patients, 28 had their stents removed as a result of strictures resolution. Eight patients underwent ERC and repeated stent deployment as a result of recurrence of the strictures. Finally, 21 out of 41 (51%) patients with biliary stricture were completely treated by endoscopic therapy during the observation period (median 873 days: range 77–2060). By multivariate analysis, biliary leakage was associated with stent deployment failure. Endoscopic deployment of plastic stents is a first‐line therapy for patients with biliary stricture after LDLT.


Clinical Gastroenterology and Hepatology | 2008

Endoscopic deployment of multiple JOSTENT SelfX is effective and safe in treatment of malignant hilar biliary strictures.

Hirofumi Kawamoto; Koichiro Tsutsumi; Ryo Harada; Masakuni Fujii; Hironari Kato; Ken Hirao; Naoko Kurihara; Takashi Nakanishi; Osamu Mizuno; Etsuji Ishida; Tsuneyoshi Ogawa; Hirotoshi Fukatsu; Kohsaku Sakaguchi

BACKGROUND & AIMS For the treatment of unresectable biliary tract carcinoma with hilar biliary stricture, antitumor therapy and biliary stenting should be addressed in terms of prolonged survival with a good quality of life. However, the endoscopic management of malignant hilar biliary strictures is difficult even for an expert endoscopist. We evaluated the efficacy and safety of the endoscopic deployment of multiple JOSTENT SelfX units in patients with hilar biliary strictures treated with or without chemotherapy. METHODS Between November 2003 and December 2006, endoscopic deployment of multiple JOSTENT SelfX units in hilar biliary strictures by using a partial stent-in-stent procedure was performed on 41 consecutive patients with primary cholangiocarcinoma (n = 34) and gallbladder carcinoma (n = 7) at a gastroenterologic center of Okayama University Hospital. Thirty-three patients were treated with gemcitabine (n = 25) or S-1 (n = 8). RESULTS Metallic stent deployment was successfully accomplished in all cases via only endoscopic procedures. During the follow-up period (mean, 210 days), mean patency time was 150 days, and metallic stent obstruction occurred in 15 cases (37%). Although a repeat intervention was required in all metallic stent obstructed cases, the deployment of the second metallic or plastic stent was completed successfully. The remaining 26 cases (63%) required no interventions. The median overall survival period was only 235 days. However, that of the patients receiving chemotherapy was 392 days. CONCLUSIONS Endoscopic partial stent-in-stent deployment with multiple JOSTENT SelfX prostheses is effective and safe for the treatment of malignant hilar biliary stricture even in patients receiving chemotherapy.


European Journal of Radiology | 2010

Prevention of biliary complication in radiofrequency ablation for hepatocellular carcinoma—Cooling effect by endoscopic nasobiliary drainage tube

Tsuneyoshi Ogawa; Hirofumi Kawamoto; Yoshiyuki Kobayashi; Shinichiro Nakamura; Hirokazu Miyatake; Ryo Harada; Koichiro Tsutsumi; Masakuni Fujii; Naoko Kurihara; Hironari Kato; Ken Hirao; Osamu Mizuno; Etsuji Ishida; Hiroyuki Okada; Kazuhide Yamamoto

BACKGROUND AND STUDY AIMS Biliary stricture after radiofrequency ablation (RFA) for nodules of hepatocellular carcinoma (HCC) close to major bile ducts sometimes causes septic complications and liver failure. Therefore, it may require interventional drainage for decompression during the follow-up period. The purpose of this study is to clarify the feasibility and safety of bile duct cooling using an endoscopic nasobiliary drainage (ENBD) tube in RFA for HCC close to major bile ducts. PATIENTS AND METHODS Between August 2003 and July 2007, 14 consecutive patients (14 nodules) undergoing RFA with cooling by an ENBD tube for HCCs close to major bile ducts were enrolled in this study. We infused chilled saline solution via the ENBD tube at 1ml/s to prevent heat damage during RFA. As controls, 11 patients (13 nodules) undergoing RFA without cooling close to major bile ducts between April 2001 and August 2003 were reviewed. The major outcomes for evaluation were biliary complications and the secondary outcome was local tumor recurrence. RESULTS There were no significant differences in tumor recurrence between the two groups. However, the rate of biliary complications was significantly lower in the cooling group than in the non-cooling group (0% vs. 39%, P=0.02). CONCLUSIONS Cooling of bile ducts via an ENBD tube can prevent biliary complications induced by RFA of HCC close to major bile ducts without increasing local recurrence. This technique increases indication of RFA in difficult cases.


European Journal of Radiology | 2012

Vascular patterns in nodules of intraductal papillary mucinous neoplasms depicted under contrast-enhanced ultrasonography are helpful for evaluating malignant potential

Naoko Kurihara; Hirofumi Kawamoto; Yoshiyuki Kobayashi; Yuko Okamoto; Naoki Yamamoto; Koichiro Tsutsumi; Masakuni Fujii; Hironari Kato; Kazuhide Yamamoto

OBJECTIVES The purpose of this study is to evaluate the feasibility of contrast-enhanced ultrasonography (CE-US) to differentiate between benign and malignant intraductal papillary mucinous neoplasms (IPMN). PATIENTS AND METHODS Contrast-enhanced ultrasonography with a contrast agent was performed on 22 consecutive patients with IPMN suspected of being malignant. This revealed 10 carcinomas, 1 borderline lesion and 11 adenomas. All patients underwent surgery, and the histological diagnosis was confirmed by examination of resected specimens. CE-US was performed using a contrast agent. The detection rates of mural nodules were compared between CE-US and contrast-enhanced computed tomography (CE-CT), and the imaging of mural nodules depicted under CE-US was analyzed. RESULTS Seventeen of 22 resected specimens (77.3%) had mural nodules. There was no significant difference in the detection rate between CE-US (n=15; 88.2%) and CE-CT (n=12; 70.6%). In 12 (80.0%) of these patients, CE-US revealed small vessels in the mural nodule. The spotty or linear-shaped pattern was detected in 4 patients and the branch-shaped pattern in 8. The branch-shaped pattern lesion was associated with carcinoma. These mural nodules were 10mm or more in height. In the perfusion image phase, cystic walls and mural nodules were also enhanced in all cases. CONCLUSION The vessel shapes of the mural nodules depicted under CE-US were associated with size and pathological findings. These results suggested that CE-US with a contrast agent is a powerful modality with which to evaluate the malignant potential of IPMN.


Pancreas | 2010

Single-pattern convergence of K-ras mutation correlates with surgical indication of intraductal papillary mucinous neoplasms.

Osamu Mizuno; Hirofumi Kawamoto; Naoki Yamamoto; Shigeru Horiguchi; Koichiro Tsutsumi; Masakuni Fujii; Hironari Kato; Ken Hirao; Naoko Kurihara; Etsuji Ishida; Tsuneyoshi Ogawa; Hiroyuki Okada; Kazuhide Yamamoto

Objectives: One or more patterns of 6 K-ras mutations are detected in cells from the pancreatic juice of patients with intraductal papillary mucinous neoplasms (IPMNs). We investigated whether these mutations are associated with malignant progression. Methods: Between January 2002 and December 2007, 53 patients with IPMN were subjected to collection of pure pancreatic juice to evaluate K-ras mutation. According to the histological and radiological findings, the IPMNs were classified into 4 groups: carcinoma group, adenoma group, high-risk group, and low-risk group. We retrospectively investigated the mutation with these groups. Results: In patients with a positive K-ras mutation, a single pattern of K-ras mutation was observed in 80% (8/10) of the carcinoma group, in 71% (5/7) of the adenoma group, in 40% (2/5) of the high-risk group, and in 38% (8/21) of the low-risk group. The rate of a single pattern of K-ras mutation decreased in a stepwise order (P = 0.017). The incidence of a single pattern of K-ras mutation was significantly higher in the patients who received surgical therapy (75%, 12/16) than in those who did not (38%, 10/26; P = 0.033). Conclusions: The present study suggests that the single-clonal convergence of K-ras mutation is associated with the malignant progression of IPMNs.


World Journal of Gastrointestinal Endoscopy | 2015

Metallic stent insertion with double-balloon endoscopy for malignant afferent loop obstruction

Masakuni Fujii; Shuhei Ishiyama; Hiroaki Saito; Mamoru Ito; Akiko Fujiwara; Takefumi Niguma; Masao Yoshioka; Junji Shiode

Progress in double-balloon endoscopy (DBE) has allowed for the diagnosis and treatment of disease in the postoperative bowel. For example, a short DBE, which has a 2.8 mm working channel and 152 cm working length, is useful for endoscopic retrograde cholangiopancreatography in bowel disease patients. However, afferent loop and Roux-limb obstruction, though rare, is caused by postoperative recurrence of biliary tract cancer with intractable complications. Most of the clinical findings involving these complications are relatively nonspecific and include abdominal pain, nausea, vomiting, fever, and obstructive jaundice. Treatments by surgery, percutaneous transhepatic biliary drainage, percutaneous enteral stent insertion, and endoscopic therapy have been reported. The general conditions of patients with these complications are poor due to cancer progression; therefore, a less invasive treatment is better. We report on the usefulness of metallic stent insertion using an overtube for afferent loop and Roux-limb obstruction caused by postoperative recurrence of biliary tract cancer under short DBE in two patients with complexly reconstructed intestines.


Clinical Journal of Gastroenterology | 2014

A case of follicular cholangitis mimicking hilar cholangiocarcinoma

Masakuni Fujii; Junji Shiode; Takefumi Niguma; Mamoru Ito; Shuhei Ishiyama; Akiko Fujiwara; Soichiro Nose; Masao Yoshioka; Tetsushige Mimura

AbstractFollicular cholangitis is a sclerosing cholangitis with hilar biliary stricture that must be differentiated from both immunoglobulin G4-related sclerosing cholangitis and primary sclerosing cholangitis. This disorder is extremely rare and difficult to distinguish from hilar biliary cholangiocarcinoma. We report here a case of a Japanese female patient in her 60s with this disease. The patient visited a family doctor for itching and general fatigue. Blood examination showed elevated hepatobiliary enzyme levels. Various imaging studies showed dilation of the bilateral intrahepatic bile duct and wide stenosis from the proximal bile duct to the right and left hepatic duct. They also showed the enlargement of multiple lymph nodes in the hepatoduodenal ligament, periaorta, and mesocolon. Based on endoscopic retrograde cholangiopancreatography-directed brush cytology, we diagnosed this patient with hilar cholangiocarcinoma and performed left trisegmentectomy of the liver. The pathology results showed that the wall from the bilateral hepatic duct to the proximal bile duct had thickened irregularly with dense fibrosis and a marked formation of lymph follicles. The mucosal epithelia did not have malignant findings. The diagnosis was follicular cholangitis. This case indicates that follicular cholangitis should be considered as a differential diagnosis of hilar biliary stricture.


Journal of Medical Case Reports | 2014

A solid pseudopapillary neoplasm without cysts that occurred in a patient diagnosed by endoscopic ultrasound-guided fine-needle aspiration: a case report

Masakuni Fujii; Masao Yoshioka; Takefumi Niguma; Hiroaki Saito; Toru Kojima; Soichiro Nose; Junji Shiode

IntroductionSolid pseudopapillary neoplasm of the pancreas is a rare neoplasm that has been reported to account for between 0.17% and 2.7% of all non-endocrine tumors of the pancreas. It is usually seen in young women. Because solid pseudopapillary neoplasms are rarely aggressive and have low-grade malignant potential and an excellent prognosis after complete resection, it is an ideal pancreatic tumor for treatment by minimally invasive surgery. Therefore, making an accurate pre-operative diagnosis is very important.Case presentationA 24-year-old Japanese man who had been found to have mild transaminase elevations at a medical check-up visited our hospital for further examination. Abdominal computed tomography showed a 40mm-diameter tumor in the pancreatic tail and mild fatty liver. He was admitted to our hospital for additional examination. The abdominal contrast-enhanced computed tomography scan taken at our institution showed an increasingly enhanced mass of 40mm diameter in the pancreatic tail. Ultrasonography showed a low-level echoic mass of 35mm diameter in the pancreatic tail. T1-weighted magnetic resonance imaging showed low signal intensity in the tail of the pancreas. T2-weighted magnetic resonance imaging showed high signal intensity there. Diffusion magnetic resonance imaging showed high signal intensity. An endoscopic ultrasound yielded the same results as the abdominal ultrasonogram. In addition, [18F]-fluorodeoxyglucose positron emission tomography/computed tomography showed abnormal accumulation (maximum standardized uptake value, 6.53). This finding raised our suspicion of a pancreatic malignant tumor. However, the patient could not be confidently diagnosed solely on the basis of imaging. Endoscopic ultrasound-guided fine-needle aspiration was performed, which led us to a diagnosis of solid pseudopapillary neoplasm. On that basis, we performed minimally invasive surgery (spleen-preserving laparoscopic distal pancreatectomy).ConclusionAtypical solid pseudopapillary neoplasm without cysts should be considered when diagnosing pancreatic tumors. A definitive pre-operative diagnosis of solid pseudopapillary neoplasm made on the basis of endoscopic ultrasound-guided fine-needle aspiration can guide the surgical approach used.


Internal Medicine | 2018

Rare Case of Pancreatic Cystic Lymphangioma

Masakuni Fujii; Hiroaki Saito; Masao Yoshioka; Junji Shiode

Pancreatic cystic lymphangioma is an extremely rare tumor. The characteristic imaging findings are poorly defined, and distinguishing between this disease and other pancreatic cyst-related tumors is very difficult. We herein report a case of a Japanese woman in her 50s with this lesion, located in the tail of the pancreas. Pancreatic cystic lymphangioma should therefore be considered in the differential diagnosis of pancreatic cystic lesions. Laparoscopic resection can be a useful, minimally invasive surgical approach for treating these cysts as well as for the treatment of benign or low-grade malignant tumors located in the pancreatic body or tail.


Internal Medicine | 2018

Whipple's Disease: A Case Report with Long-term Endoscopic Follow-up.

Hiroaki Saito; Junji Shiode; Shogen Ohya; Atsushi Yao; Shunsuke Saito; Masakuni Fujii; Mamoru Itoh; Shuhei Ishiyama; Akiko Fujiwara; Junichiro Nasu; Masao Yoshioka; Kazuhide Yamamoto

A 72-year-old man presented with anorexia and 15-kg weight loss over 3 years. Endoscopy revealed yellow, shaggy mucosa alternating with erythematous, eroded mucosa in the duodenum. Biopsy specimens showed massive infiltration of periodic acid-Schiff-positive macrophages in the lamina propria, consistent with Whipples disease. The patient was treated with intravenous ceftriaxone for four weeks, followed by oral trimethoprim-sulfamethoxazole. His condition improved, and he gradually gained weight. Although the endoscopic findings improved with continuous trimethoprim-sulfamethoxazole administration, macrophage infiltration of the duodenal mucosa persisted. However, the patient has been symptom-free for eight years.

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