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Featured researches published by Tomotaka Akatsu.


Digestive Diseases and Sciences | 2006

Can Endoscopic Ultrasonography Differentiate Nonneoplastic from Neoplastic Gallbladder Polyps

Tomotaka Akatsu; Koichi Aiura; Motohide Shimazu; Masakazu Ueda; Go Wakabayashi; Minoru Tanabe; Shigeyuki Kawachi; Masaki Kitajima

The present study aimed to clarify the endoscopic ultrasonography (EUS) features of nonneoplastic (cholesterol polyps and adenomyomatosis) and neoplastic (adenoma and adenocarcinoma) gallbladder polyps and to evaluate the effectiveness and limitation of EUS in the differential diagnosis of these lesions. We retrospectively compared EUS images with histologic findings in 29 surgical cases with gallbladder polyps with a diameter of 10 to 20 mm. Those cases were indicated for surgery based on the findings of a sessile appearance, a solitary lesion, low echogenicity, and/or a lobulated surface. Six of 10 cholesterol polyps were atypically seen as partially or completely hypoechoic due to predominant proliferation of glandular epithelia. Nine of 10 cholesterol polyps demonstrated an aggregation of hyperechoic spots, which represented multiple granules of cholesterosis. All adenomyomatoses (n = 10) showed multiple microcysts, which corresponded to proliferated Rokitansky-Aschoff sinuses. However, three of nine neoplastic lesions (three adenomas and six adenocarcinomas) showed one of these signs due to concomitant cholesterosis (n = 2) or proliferated Rokitansky-Aschoff sinuses (n = 1). In conclusion, 69% (20/29) of gallbladder polyps larger than 10 mm that were preoperatively suspected of malignancy were nonneoplastic. An aggregation of hyperechoic spots and multiple microcysts are considered to be important predictive factors for cholesterol polyps and adenomyomatosis, respectively. However, we should caution that these findings can also occur in neoplastic polyps when they contain a concomitant nonneoplastic component (cholesterosis or proliferated Rokitansky-Aschoff sinuses).


World Journal of Surgery | 2005

Gallstone Disease after Extended (D2) Lymph Node Dissection for Gastric Cancer

Tomotaka Akatsu; Masashi Yoshida; Tetsuro Kubota; Motohide Shimazu; Masakazu Ueda; Yoshihide Otani; Go Wakabayashi; Koichi Aiura; Minoru Tanabe; Toshiharu Furukawa; Yoshiro Saikawa; Shigeyuki Kawachi; Yukako Akatsu; Koichiro Kumai; Masaki Kitajima

Few studies have reported the incidence and clinical outcomes of gallstone disease after extended (D2) lymph node dissection for gastric cancer. The present study was designed to retrospectively compare limited (D1) and D2 dissections in terms of gallstone formation, presentation of gallstones, and surgery for gallstone disease. A total of 805 Japanese gastric cancer patients (595 male, 210 female) who underwent curative resection with D1 (n = 490) or D2 (n= 315) dissection were retrospectively reviewed. Of those subjects followed for 70.5 ± 44.3 months (range: 2-196 months), 102 (12.7%) developed gallstones. The incidence of gallstone formation was higher in the D2 group than in the D1 group (17.8% vs. 9.4%, p= 0.001). The interval between gastrectomy and detection of gallstones was shorter in the D2 group than in the Dl group (18.8 ± 11.4 months vs. 29.4 ± 18.3 months, p = 0.002). Of those with gallstones followed for 48.0 ± 28.6 months (range: 1-158 months), 74 (72.5%) remained asymptomatic, and 15 (14.7%) experienced mild biliary pain. Thirteen patients (12.7%) developed recurrent biliary pain (n = 3) or biliary complications (n = 10; 6 acute cholecystitis, 3 obstructive jaundice, and 1 cholangitis), and required surgical treatment. Surgery was more frequently sought in the D2 group than in the D1 group (19.5% vs. 4.3%, p = 0.033). In conclusion, patients with D2 dissection developed gallstones more frequently and earlier than patients with D1 dissection. Of those with gallstones, patients with D2 dissection required surgery more often than patients with D1 dissection. A closer follow-up should be mandatory for gallstone disease after D2 dissection, but further studies are needed before generalizations can be made.


Surgery Today | 2007

Pseudoaneurysm of the cystic artery secondary to cholecystitis as a cause of hemobilia: report of a case.

Tomotaka Akatsu; Minoru Tanabe; Tomohiro Shimizu; Kan Handa; Shigeyuki Kawachi; Koichi Aiura; Masakazu Ueda; Motohide Shimazu; Masaki Kitajima

Spontaneous intracholecystic bleeding is very rare. We report herein a very rare case of a pseudoaneurysm of the cystic artery due to acute cholecystitis. A 58-year-old man presented at the emergency department complaining of colicky pain in the right upper quadrant. Dynamic magnetic resonance imaging demonstrated an early-enhanced pooling of contrast material (suggestive of a pseudoaneurysm of the cystic artery) inside the neck of the gallbladder. After the proximal control of the hepatic artery, the patient underwent a cholecystectomy and a ligation of the cystic artery. The resected specimen of the gallbladder showed evidence of a massive intracholecystic hematoma. Proximal to the impacted gallstone in the neck, a 2-cm diameter saccular-type pseudoaneurysm was identified. Although a pseudoaneurysm of the cystic artery is very rare, it should be included in the differential diagnosis of hemobilia. Once the pseudoaneurysm is confirmed, its embolization before a cholecystectomy (which can be attempted laparoscopically) may be useful to ensure the safety of the patient.


Journal of Gastroenterology | 2004

Hepatic artery pseudoaneurysm associated with cholecystitis that ruptured into the gallbladder

Tomotaka Akatsu; Shinobu Hayashi; Tomohisa Egawa; Masakazu Doi; Atsushi Nagashima; Mitsuhide Kitano; Takashi Yamane; Hiroshi Yoshii; Masaki Kitajima

Pseudoaneurysm of the hepatic artery due to cholecystitis may be very rare, and in our survey of the literature, the present case report is the first case of such a pseudoaneurysm. A 64-year-old woman presented with upper gastrointestinal bleeding and severe epigastric pain. Upper gastrointestinal tract endoscopy revealed blood coming out of the papilla of Vater. Color-Doppler ultrasound imaging showed a pulsatile wave pattern in an echogenic lesion inside the gallbladder. Contrast-enhanced computed tomography demonstrated a 3-cm pseudoaneurysm in the distended gallbladder. Angiography disclosed extravasation originating from the right hepatic artery. Emergency selective transcatheter arterial embolization was performed, with intravascular stainless steel microcoils, and complete occlusion of the pseudoaneurysm was achieved. The patient underwent cholecystectomy with resection of the extrahepatic bile duct and biliary reconstruction in a Roux-en-Y fashion. Macroscopically, the resected gallbladder contained clotted blood and multiple cholesterol stones. Microscopically, the mucosa of the gallbladder showed extensive necrosis and many inflammatory cells. The final diagnosis was pseudoaneurysm of the hepatic artery associated with calculous gangrenous cholecystitis. Although the mechanism of the pseudoaneurysm remains speculative, severe inflammatory reaction in the gallbladder may have infiltrated the liver parenchyma and may have eroded the wall of the hepatic artery, thus forming a pseudoaneurysm. Hemobilia is one of the important differential diagnoses when unexplained gastrointestinal bleeding is observed, especially in patients with hepatobiliary diseases.


Journal of Gastroenterology | 2004

Intraductal growth of a nonfunctioning endocrine tumor of the pancreas.

Tomotaka Akatsu; Go Wakabayashi; Koichi Aiura; Kazuhiro Suganuma; Yutaka Takigawa; Masahiro Wada; Shigeyuki Kawachi; Minoru Tanabe; Masakazu Ueda; Motohide Shimazu; Michiie Sakamoto; Masaki Kitajima

Intraductal growth of nonfunctioning endocrine tumors of the pancreas may be very rare, and our survey of literature shows only two cases have been described. We report a case of a 43-year-old man with a nonfunctioning endocrine tumor of the pancreas that uniquely grew within the lumen of the main pancreatic duct (MPD) without ductal involvement and completely obstructed the MPD. Endoscopic ultrasonography (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) were very helpful to delineate the intraductal growth of the tumor and to determine the resection line of the pancreas. A nonfunctioning pancreatic endocrine tumor is important to consider on differential diagnoses when complete obstruction of the MPD is demonstrated on ERCP. It is speculated that the tumor originated from precursor cells of the pancreatic duct or islet cells adjacent to the MPD and slowly proliferated within the lumen of the MPD.


Surgery Today | 2009

Perineal hernia as a rare complication after laparoscopic abdominoperineal resection: Report of a case

Tomotaka Akatsu; Shinji Murai; Satoshi Kamiya; Kenji Kojima; Yoshikazu Mizuhashi; Hirotoshi Hasegawa; Yuko Kitagawa

We report what seems to be the second documented case of perineal hernia after laparoscopic abdominoperineal resection (APR) and describe its successful repair with transperineal intraperitoneal mesh. An 89-year-old woman complained of a large, painful perineal swelling 4 months after APR for rectal cancer. Computed tomography (CT) showed small intestine protruding through the pelvic floor into the perineal area. However, opening of the hernia sac revealed no intra-abdominal adhesions. An oval, 8 × 12 cm Bard Composix Kugel Patch (Davol, Cranston, RI, USA) was inserted into the intraperitoneal space and secured over the defect in the pelvic floor; then firmly attached to the pelvic wall with 16 interrupted nonabsorbable sutures. There has been no sign of hernia recurrence in 10 months of follow-up. We speculate that because laparoscopic surgery is minimally invasive, fewer postoperative adhesions in the abdominal cavity can result in the small bowel sliding more readily into the perineal area. Based on our experience, perineal hernia after laparoscopic APR can be repaired easily and effectively with a Composix Kugel Patch.


Surgery Today | 2007

[Signet-Ring Cell Carcinoma of the Ampulla of Vater--Report of a Case].

Tomotaka Akatsu; Koichi Aiura; Shin Takahashi; Kaori Kameyama; Masaki Kitajima; Yuko Kitagawa

Signet-ring cell carcinoma (SRCC) of the ampulla of Vater is uncommon, and only 13 cases have been previously described. We herein report a rare case of a 43-year-old woman with SRCC in the ampulla of Vater. Although this histologic type of cancer generally predicts a poor prognosis elsewhere in the gastrointestinal tract, the present patient has survived with no evidence of recurrence for 7.5 years. The patient was hospitalized for pruritus and jaundice. She underwent a pancreaticoduodenectomy with an extended lymphadenectomy for ampullary carcinoma. This neoplasm was classified as AcdbBi, 2.0 × 1.8 cm, ulcerative type, Panc0, Du2, T2N0M(−), Stage II according to the Japanese Classification on Cancer of the Biliary Tract. Unfortunately, previous reports of ampullary SRCC have been limited to short-term follow-ups with a median period of only 12 months (range, 6–134 months), and long-term survival (more than 5 years) was only documented in two cases without lymph node metastasis (including the present case). In conclusion, the experience gained in the present and previous cases suggests that long-term survival is possible following a curative resection in selected patients with ampullary SRCC without nodal involvement. Due to the lack of sufficient evidence, additional reports are warranted to determine whether SRCC also portends a poor prognosis in patients with ampullary cancer.


Surgery Today | 2006

Inflammatory Pseudotumor of the Liver Masquerading as Hepatocellular Carcinoma After a Hepatitis B Virus Infection : Report of a Case

Tomotaka Akatsu; Go Wakabayashi; Akihiro Tanimoto; Kaori Kameyama; Masaki Kitajima

We report a rare case of hepatic inflammatory pseudotumor (IPT) after a hepatitis B virus (HBV) infection. Early contrast enhancement on computed tomography (CT) with a washout phenomenon at the delayed phase, and depleted Kupffer cell function on superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) suggested hepatocellular carcinoma (HCC). However, the lack of a tumor capsule, absence of liver cirrhosis, and normal serum levels of α-fetoprotein and PIVKA-II (protein induced by vitamin K absence; descarboxyprothrombin) contradicted this diagnosis. We excised the tumor to exclude malignancy, and the histopathological diagnosis was IPT. Recent evidence suggests that this entity has changed from an extremely rare pathology to an established disease. Thus, IPT should be considered in the differential diagnosis of a liver mass with an infectious–inflammatory antecedent. Although surgery is not mandatory, surgical removal is recommended if there is a possibility of malignancy. Further investigations are warranted to elucidate the mechanisms of IPT developing after an HBV infection.


Journal of Gastroenterology | 2006

Gallbladder carcinoma with osteoclast-like giant cells

Tomotaka Akatsu; Kaori Kameyama; Shigeyuki Kawachi; Minoru Tanabe; Koichi Aiura; Go Wakabayashi; Masakazu Ueda; Motohide Shimazu; Masaki Kitajima

Extraskeletal tumors containing multinucleated, osteoclast-like giant cells (OGCs) are uncommon. These neoplasms are most frequently reported in the breast and pancreas. Recently, some authors have suggested that carcinomas containing OGCs may represent a distinct clinicopathological entity with a more favorable prognosis. Occurrence in the gallbladder is extremely rare, with only one previous case. We report here on an additional case of gallbladder carcinoma with an infiltrate of OGCs. A 72-year-old woman presented with postprandial abdominal pain and was found to have a mass in the body of the gallbladder with direct liver invasion. Histological examination showed an adenosquamous carcinoma with an infiltrate of benign OGCs. Immunohistochemical analysis demonstrated that the giant cells were of histiocytic origin. The patient survived for 6 years without evidence of recurrence. This case adds to a small body of literature on gallbladder carcinoma with OGCs. Further studies are required to clearly define the prognostic significance of these giant cells in gallbladder cancer and the differences between adenosquamous carcinoma with OGCs and other gallbladder carcinomas (such as adenocarcinoma and squamous cell carcinoma) with those cells.


Journal of Gastroenterology and Hepatology | 2004

Emergency embolization of a ruptured pancreaticoduodenal artery aneurysm associated with the median arcuate ligament syndrome

Tomotaka Akatsu; Shinobu Hayashi; Takashi Yamane; Hiroshi Yoshii; Masaki Kitajima

To the Editor, Pancreaticoduodenal artery (PDA) aneurysms are particularly uncommon, and account for only 2% of all splanchnic artery aneurysms. However, the majority of patients with PDA aneurysms present with life-threatening bleeding. Emergency surgery has been the standard treatment for ruptured aneurysms of the PDA. However, even in operable cases, the mortality rate is 43.6%. Transcatheter arterial embolization (TAE) is emerging as a safe and effective alternative to surgery. We herein report a case of a ruptured PDA aneurysm associated with the median arcuate ligament syndrome that was saved by emergency TAE with microcoils. A 49-year-old woman presented at our institution with sudden and severe epigastric pain that lasted 1 h. The patient had a 6-month history of postprandial abdominal pain, nausea, emesis, and mild weight loss. The patient was in cardiovascular shock upon presentation. She received rapid fluid resuscitation and was stabilized. Contrast-enhanced computed tomography demonstrated a peripancreatic aneurysm with a surrounding retroperitoneal hematoma. Emergency superior mesenteric arteriography disclosed extravasation from a saccular aneurysm at the origin of the posterior inferior PDA that was 1 cm in diameter. Stenosis of the celiac axis was observed. The celiac arterial territory was mainly vascularized by the superior mesenteric artery (SMA) through the PDA arcade (Fig. 1a). Immediately after diagnostic angiography, superselective TAE was carried out. Intravascular stainless steel microcoils were placed in both the proximal and distal portions of the origin of the aneurysm via the SMA with the Tracker Vascular Access System (Target Therapeutics, Fremont, CA, USA). Subsequent angiography showed complete occlusion of the aneurysm (Fig. 1b). Increased serum levels of transaminases and amylase were not observed. She has been well without recurrent bleeding for 2 years. Although the PDA arcade is anatomically complicated, current microcatheters and guidewires allow for superselective catheterization of the PDA. The high selectivity of embolization contributes to obviating pancreatic and duodenal infarction. We embolized the segmental parental artery of the aneurysm because it appeared diseased and fragile. Intravascular stainless steel microcoils were used because of their effects of more definitive vascular occlusion in comparison with Gelfoam, which usually resorbs within several weeks. We believe superselective TAE with microcoils is the preferred primary treatment of choice for ruptured aneurysms of the PDA. In addition to the celiac axis stenosis, we observed blood flow from the SMA to the celiac arterial territories. Therefore, an increased amount of blood flow through the PDA arcade may have resulted in the formation of the aneurysm. Moreover, the patient had a history of postprandial abdominal pain, nausea, emesis, and mild weight loss. The following clinical triad

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Minoru Tanabe

Tokyo Medical and Dental University

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Go Wakabayashi

Iwate Medical University

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