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Dive into the research topics where Kiyotaka Yabuki is active.

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Featured researches published by Kiyotaka Yabuki.


Journal of Gastroenterology | 2003

Multiple esophagogastric granular cell tumors.

Hiroshi Maekawa; Takeo Maekawa; Kiyotaka Yabuki; Kouichi Sato; Yoshihisa Tamazaki; Keizou Kudo; Ryo Wada; Michio Matsumoto

Multiple granular cell tumors of the esophagus and the stomach found in a 53-year-old man are reported. One lesion was detected within the lower thoracic esophagus and seven lesions were detected in the stomach. The esophageal tumor was resected endoscopically, and gastrectomy was performed for the multiple gastric lesions. Histologically, the tumors consisted of spindle or polyhedral cells and the cytoplasm contained punctated eosinophilic granules with positive immunohistochemical staining for S-100 protein. The tumors were mainly located in the submucosal layer. Some tumor cells were seen in the mucosae propria and the muscularis propria. The tumor cells were only slightly positive for p53- and Ki-67-immunohistochemical stainings. Based on these findings, we diagnosed the granular cell tumors as benign. Granular cell tumor is comparatively rare in clinical practice, but a few such tumors have been seen in the digestive tract. A few cases of multiple esophagogastric granular cell tumors have also been reported in the literature.


Surgery Today | 2000

Primary gastric lymphoma with spontaneous perforation: report of a case.

Kiyotaka Yabuki; Yoshihisa Tamasaki; Koichi Satoh; Takeo Maekawa; Michio Matsumoto

Abstract Primary gastric lymphoma with spontaneous perforation is rare. We report herein the case of a 53-year-old-man who was admitted to our hospital with severe epigastralgia. Emergency endoscopic examination showed a perforated gastric tumor in the lower body of the greater curvature, and a distal subtotal gastrectomy with lymph node dissection was performed. The resected tumor measured 10.0 × 8.0 cm and was associated with an area of ulceration, 8.0 × 6.0 cm in size, and perforation, 1.0 × 0.5 cm in size. Pathological examination confirmed a diagnosis of B-cell malignant lymphoma of the diffuse, medium-sized cell type. According to the Ann Arbor and Naqvi classifications, the lymphoma was stage II and stage III, respectively. Postoperative adjuvant chemotherapy comprising cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) was given. The patient is currently well with no signs of recurrence, 2 years 4 months after his operation.


Journal of Gastroenterology | 1999

CYSTIC LYMPHANGIOMAS OF THE COLON

Koichi Sato; Takeo Maekawa; Kiyotaka Yabuki; Natsumi Tomita; Masanobu Eguchi; Michio Matsumoto; Noriyoshi Sugiyama

Abstract: We report a patient with cystic lymphangiomas diagnosed by endoscopic ultrasonography and resected by partial polypectomy. A 42-year-old woman consulted a nearby physician because of a positive fecal occult blood test. Barium enema and colonoscopy revealed the presence of abnormalities. On March 11, 1997, she was admitted to our department for further evaluation and treatment. A barium enema examination revealed two protruding lesions in the transverse colon. Colonoscopy showed a teardrop-type mass in the left side of the transverse colon. The mass was cushion-sign positive, and its shape readily changed on respiration and with changes in body position. Another superficial smooth mass was found in the right side of the transverse colon. Ultrasonography of the colon confirmed the presence of a submucosal mass showing a cyst-like pattern. Cystic lymphangiomas were diagnosed and resected endoscopically. Histopathological examination revealed markedly dilated ducts consisting of a single layer of endothelial cells in the submucosa of the colon. The diagnosis was cystic lymphangioma.


Journal of Gastroenterology | 2003

A case of triple synchronous cancers occurring in the gallbladder, common bile duct, and pancreas.

Koichi Sato; Takeo Maekawa; Kiyotaka Yabuki; Yoshihisa Tamasaki; Hiroshi Maekawa; Keizo Kudo; Hironobu Sengoku; Ikukyo Kawa; Ryo Wada; Michio Matsumoto

We report a 74-year-old man with triple synchronous cancers occurring in the gallbladder, common bile duct, and pancreas. The patient had consulted a nearby physician because of epigastralgia and icterus. On September 30, 1997, the patient was admitted to our department for further evaluation and treatment. Abdominal computed tomography (CT) showed dilatation of the common bile duct, cystic duct, and intrahepatic bile duct, and swelling of the gallbladder. On CT, the wall of the distal common bile duct was thick and a low-density mass was detected on the left side. Cholangiography, performed via percutaneous transhepatic cholangiodrainage (PTCD), revealed stenosis of the distal common bile duct. Endoscopic retrograde pancreatography (ERP) showed marked dilatation of the main pancreatic duct. On October 17, 1997, pancreatoduodenectomy was performed under the diagnosis of carcinoma of common bile duct and pancreas. Histopathological examination revealed poorly differentiated tubular adenocarcinoma of the common bile duct, well-differentiated tubular adenocarcinoma of the gallbladder, and mucinous cystadenocarcinoma of the pancreas. These three tumors were histopathologically different. Moreover, p53-positive nuclei were recognized only in the pancreas tumor. These findings suggested that the oncogenic mechanisms of multiple synchronous cancers were not the result of only abnormal DNA reparative mechanisms.


Digestive Endoscopy | 2000

A case of pancreatic serous cystadenoma with obstructive jaundice

Takeo Maekawa; Kiyotaka Yabuki; Koichi Satoh; Yoshihisa Tamasaki; Takayuki Amano; Hironobu Sengoku; Kaoru Ogawa; Michio Matsumoto

A 62‐year‐old man with precordial pain and fever consulted a local practitioner. Blood tests revealed jaundice. Acute cholecystitis was diagnosed on ultrasonographic examination, and percutaneous transluminal gall‐bladder drainage was performed. The patient was referred to the Department of Surgery for operation. Imaging studies performed via a drain disclosed compression and stenosis of the lower portion of the common bile duct. A computed tomographic scan showed a multilocular nodule‐like low‐density area measuring 2.0 × 2.0 cm in diameter at the head of the pancreas. Endoscopic retrograde cholangiopancreatography disclosed compression and stenosis of the main pancreatic duct at the head of the pancreas. Angiographic examination revealed encasement of the intrapancreatic branch of the posterior pancreatic arcade, located in the same area as the compression stenosis of the bile duct. The results of imaging studies suggested cancer of the head of the pancreas, and a pancreatoduodenectomy was performed. The resected specimen included a mass measuring 3.5 × 2.7 × 1.7 cm, which was located at the head of the pancreas. On examination of a cut section, the mass was found to consist of small multilocular cysts. The cysts invaded the intrapancreatic bile duct. The histopathological diagnosis was serous cystadenoma.


Digestive Endoscopy | 2000

A CASE OF GROOVE PANCREATITIS WITH DUODENAL STENOSIS

Kiyotaka Yabuki; Takeo Maekawa; Koichi Satoh; Yoshihisa Tamasaki; Hiroshi Maekawa; Takayuki Amano; Kaoru Ogawa; Kou Aonuma

A 58‐year‐old man presented with a 2‐month history of nausea and vomiting. Blood levels of hepatic enzymes and pancreatitis markers were slightly elevated. Hypotonic duodenographic and endoscopic examinations revealed stenosis encircling the descending duodenum. A computed tomography (CT) scan showed inflammatory changes in the head of the pancreas and thickening of the duodenal wall. Magnetic resonance cholangiography demonstrated stenosis of the intrapancreatic segment of the common bile duct and diffuse dilatation of the main pancreatic duct, without irregularity. At laparotomy, microscopic examination of a needle biopsy specimen of the head of pancreas revealed no evidence of malignancy. Distal gastrectomy with Billroth II anastomosis was performed. Microscopically, fibrous thickening of the duodenal wall, serositis and hyperplasia of Brunners glands were found. The presence of duodenal stenosis due to segmental pancreatitis, referred to as groove pancreatitis, was confirmed. The elevated blood levels of pancreatitis markers returned to the normal range 8 months after the operation. Ultrasonic echography and abdominal CT also revealed a marked reduction in dilatation of the extrahepatic bile duct and the main pancreatic duct. In patients suspected of having pancreatic carcinoma or regional pancreatitis, groove pancreatitis should be included in the differential diagnosis.


Digestive Endoscopy | 2002

PRIMARY GASTRIC LYMPHOMA WITH ARTERIAL BLEEDING

Kiyotaka Yabuki; Takeo Maekawa; Koichi Satoh; Yoshihisa Tamasaki; Hiroshi Maekawa; Keizo Kudo; Ikukyo Kawa; Ryo Wada; Michio Matsumoto

We experienced a case of primary gastric lymphoma with arterial bleeding. The case was an 88‐year‐old‐man who was admitted to our hospital with hematemesis. Gastroduodenal endoscopy revealed a gastric ulcerating tumor with arterial bleeding in the posterior wall of the angular gastric region, and a distal subtotal gastrectomy with lymph node dissection was performed. The resected tumor measured 7.0 × 3.0 cm in size with a blood vessel visible in the bottom of the ulcer. Pathologic examination confirmed a diagnosis of B‐cell malignant lymphoma of the diffuse large cell type. Metastasis was detected in nos 3 and 5 lymph nodes. According to the Ann Arbor and Naquvi classifications, the lymphoma was stage IIE and II, respectively. One year and 10 months after the operation, a computed tomography scan revealed a few swollen lymph nodes around the abdominal aorta. Recurrence of lymphoma was confirmed and chemotherapy comprising cyclophosphamide, doxorubin, vincristine and predonisolone was given at half the ordinary adult dose.


Journal of Gastroenterology | 2002

Extensive hemorrhagic erosive gastritis associated with acute pancreatitis successfully treated with a somatostatin analog

Kiyotaka Yabuki; Takeo Maekawa; Koichi Satoh; Yoshihisa Tamasaki; Hiroshi Maekawa; Keizo Kudoh; Eizaburo Aoki

In massive hemorrhage from acute gastric mucosal lesions, it is occasionally difficult to control the bleeding with nonsurgical therapy. We used the somatostatin analog, octreotide, which suppresses gastric and pancreatic function, to treat severe hemorrhagic erosive gastritis in a patient with acute pancreatitis. A 22-year-old man presented with epigastralgia and melena. Blood levels of pancreatitis markers were elevated. Computed tomography revealed diffuse enlargement of the pancreas, without fluid collection around the organ. An endoscopic examination showed extensive hemorrhagic erosions over almost the whole gastric mucosa. We diagnosed extensive hemorrhagic erosive gastritis with acute pancreatitis. A protease inhibitor (nafamostat mesilate 50 mg/day) and an H2 receptor antagonist (famotidine 40 mg/day) were administered by injection for 6 days; the patients serum and urine amylase levels fell, but the gastric erosions with hemorrhage were not attenuated. Octreotide was given subcutaneously, at a daily dose of 100 μg for 5 days, without famotidine administration. His melena disappeared, and the gastric erosions were markedly decreased. Administration of the somatostatin analog, octreotide, proved to be effective treatment in a patient with severe hemorrhagic erosive gastritis associated with acute pancreatitis.


Digestive Endoscopy | 1998

A Case of Duodenal Carcinoid Tumor Associated with Carcinoma of the Head of the Pancreas

Koichi Sato; Takeo Maekawa; Kiyotaka Yabuki; Takao Ando; Michio Matsumoto

Abstract: We describe a case of duodenal carcinoid tumor associated with carcinoma of the head of the pancreas. The patient was a 77‐year‐old man who was admitted to our hospital with jaundice and pruritus cutaneous. Carcinoma of the head of the pancreas was diagnosed on the basis of findings obtained by abdominal computed tomographic scan and endoscopic retrograde cholangiopancreatography. Upper gastrointestinal endoscopy revealed a protrusive hemorrhagic lesion with a flushed surface and a diameter of about 1 cm in the anterior wall of the duodenal bulb. On May 25, 1996, pancreaticoduodenectomy was performed. On histopathological examination, this carcinoma of the pancreatic head was found to be a well‐differentiated tubular adenocarcinoma. Immunohisto‐chemically, the protrusive lesion in the duodenal bulb stained positive for chromogranine and IMSB and was slightly positive for S‐100 protein. It was also slightly positive on Grimelius staining and negative on Masson‐Fontana staining. These findings led to a diagnosis of carcinoid tumor arising from the anterior intestinal line.


Digestive Endoscopy | 1998

A Case of Postbulbar Duodenal Ulcer with Jaundice

Takeo Maekawa; Kiyotaka Yabuki; Koichi Sato; Takanori Haba; Kaoru Ogawa; Michio Matsumoto

Abstract: A 63‐year‐old man was hospitalized because of jaundice and anorexia. An upper gastrointestinal series and hypotonic duodenography revealed circumferential sclerosis and stenosis of the duodenal wall. Endoscopic examination disclosed an ulcer, the upper margin of which was located at the papilla of Vater. The papilla was situated in the base of the ulcer. Endoscopic retrograde cholangiopancreatography disclosed mild dilatation of the common bile, intrahepatic bile and pancreatic ducts, but with neither severe stenosis nor occlusion. Nevertheless, there was some degree of circumferential compression and mild stenosis of the terminal portions of the bile and pancreatic ducts, as potential causes of obstructive jaundice in this patient. Computed tomographic examination of the abdomen revealed a tumorous lesion at the duodenal bulb. Because malignancy in the duodenum could not be ruled out, a pancreatoduodenectomy was performed. Histopathological examination showed a postbulbar duodenal ulcer, associated with inflammation of the papillary orifice and fibrosis of the region near the papilla. There was no evidence of a tumorous lesion. In this case, a postbulbar duodenal ulcer may have caused obstructive jaundice.

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