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Atsutake Okamoto

Publications and source records attributed to Atsutake Okamoto.

At least 19 recordsLinked to original sources
PubMed2007

Does moderate celiac axis stenosis identified on preoperative multidetector computed tomographic angiography predict an increased risk of complications after pancreaticoduodenectomy for malignant pancreatic tumors?

OBJECTIVES: To identify any association between celiac artery compromise found on computed tomographic angiography and the incidence of postoperative and perioperative complications. METHODS: The computed tomographic angiograms of 36 patients who underwent the Whipple procedure for pancreatic adenocarcinoma were examined retrospectively. The association between the results and surgical course was investigated. RESULTS: Twelve patients (33%) had significant postoperative complications. Ten (28%) had evidence of celiac artery stenosis. Stenosis ranged from 20% to 60%. There was no evidence of a difference between the 2 groups. CONCLUSION: There seems to be no evidence of an increased risk of postoperative or perioperative complication in patients undergoing the Whipple procedure, with a celiac stenosis of up to 60%.

Adenocarcinoma↗
PubMed2006

Pancreatic cancer with a high serum IgG4 concentration.

Differentiation between autoimmune pancreatitis and pancreatic cancer is sometimes difficult. It has been reported that serum IgG4 concentrations are significantly elevated and particularly high (>135 mg/dL) in autoimmune pancreatitis. Measurement of serum IgG4 has become a useful tool for differentiating between autoimmune pancreatitis and pancreatic cancer. However, we present a 74-year-old female with a markedly elevated serum IgG4 (433 mg/dL) who underwent pancreaticoduodenectomy for pancreatic cancer. Elevated serum IgG4 levels continued after the resection. On histology, adenocarcinoma of the pancreas accompanied with moderate lymphoplasmacytic infiltration infiltrated the lower bile duct and duodenum, but there were no findings of autoimmune pancreatitis. Although a small metastasis was detected in one parapancreatic lymph node, regional lymph nodes were swollen. Abundant IgG4-positive plasma cells infiltrated the cancerous areas of the pancreas, but only a few IgG4-positive plasma cells were detected in the noncancerous areas. Pancreatic cancer cells were not immunoreactive for IgG4. An abundant infiltration of IgG4-positive plasma cells was detected in the swollen regional lymph nodes and in the duodenal mucosa. We believe that the serum IgG4 level was elevated in this patient with pancreatic cancer as the result of an IgG4-related systemic disease that had no clinical manifestations other than lymphadenopathy.

Adenocarcinoma↗
PubMed2006

Biliopancreatic and pancreatobiliary refluxes in cases with and without pancreaticobiliary maljunction: diagnosis and clinical implications.

The sphincter of Oddi is located at the distal end of the pancreatic and bile ducts and regulates the outflow of bile and pancreatic juice. A common channel can be so long that the junction of the pancreatic and bile ducts is located outside of the duodenal wall, as occurs in pancreaticobiliary maljunction; in such cases, the action of the sphincter does not functionally affect the junction. Thus, biliopancreatic and pancreatobiliary refluxes occur, resulting in various pathological conditions in the biliary tract and in the pancreas. Biliopancreatic reflux could be confirmed by operative or postoperative T tube cholangiography, computed tomography combined with drip infusion cholangiography, histological detection of gallbladder cancer cells in the main pancreatic duct, and reflux of bile on the cut surface of the pancreas. Pancreatobiliary reflux could be diagnosed on the basis of an elevated amylase level in the bile, secretin-stimulated dynamic magnetic resonance cholangiopancreatography, and pancreatography via the minor duodenal papilla. Recently, it has become obvious that these refluxes can occur in individuals without pancreaticobiliary maljunction. Biliopancreatic reflux is related to the occurrence of acute pancreatitis, and pancreatobiliary reflux might be related to biliary carcinogenesis even in some individuals without pancreaticobiliary maljunction. Since few systemic studies exists with respect to diagnostic imaging techniques and clinical relevance of these refluxes in individuals with a normal pancreaticobiliary junction, further prospective clinical studies including appropriate management should be performed.

Bile Duct Diseases↗
PubMed2006

Sclerosing cholecystitis associated with autoimmune pancreatitis.

AIM: To evaluate the histopathological and radiological findings of the gallbladder in patients with autoimmune pancreatitis (AIP). METHODS: The radiological findings of the gallbladder of 19 AIP patients were retrospectively reviewed. Resected gallbladders of 8 AIP patients were examined histologically and were immunostained with anti-IgG4 antibody. Controls consisted of gallbladders resected for symptomatic gallstones (n = 10) and those removed during pancreatoduodenectomy for pancreatic carcinoma (n = 10), as well as extrahepatic bile ducts and pancreases removed by pancreatoduodenectomy for pancreatic carcinoma (n = 10). RESULTS: Thickening of the gallbladder wall was detected by ultrasound and/or computed tomography in 10 patients with AIP (3 severe and 7 moderate); in these patients severe stenosis of the extrahepatic bile duct was also noted. Histologically, thickening of the gallbladder was detected in 6 of 8 (75%) patients with AIP; 4 cases had transmural lymphoplasmacytic infiltration with fibrosis, and 2 cases had mucosal-based lymphoplasmacytic infiltration. Considerable transmural thickening of the extrahepatic bile duct wall with dense fibrosis and diffuse lymphoplasmacytic infiltration was detected in 7 patients. Immunohistochemically, severe or moderate infiltration of IgG4-positive plasma cells was detected in the gallbladder, bile duct, and pancreas of all 8 patients, but was not detected in controls. CONCLUSION: Gallbladder wall thickening with fibrosis and abundant infiltration of IgG4-positive plasma cells is frequently detected in patients with AIP. We propose the use of a new term, sclerosing cholecystitis, for these cases that are induced by the same mechanism as sclerosing pancreatitis or sclerosing cholangitis in AIP.

Autoimmune Diseases↗
PubMed2006

MRCP and MRI findings in 9 patients with autoimmune pancreatitis.

AIM: To evaluate magnetic resonance cholangiopancreatography (MRCP) findings in conjunction with magnetic resonance (MR) images in autoimmune pancreatitis (AIP) patients. METHODS: Nine patients with AIP underwent MRI, MRCP, endoscopic retrograde cholangiopancreatography (ERCP), computed tomography, and ultrasonography. The MRCP and MR images taken before and after steroid therapy were reviewed and compared with other imaging modalities. The MRCP findings of the AIP cases were compared to those of 10 cases with carcinoma of the head of the pancreas. RESULTS: On MRCP, the narrowed portion of the main pancreatic duct noted on ERCP was not visualized, while the non-involved segments of the main pancreatic duct were visualized. The degree of upstream dilatation of the proximal main pancreatic duct was milder than that seen in cases of pancreatic carcinoma. Stenosis or obstruction of the lower bile duct was detected in 8 patients. MR images showed enlargement of the pancreas with decreased signal intensity on T1-weighted MR images, increased signal intensity on T2-weighted MR images, and, in 3 patients, a hypointense capsule-like rim. After steroid therapy, the previously not visualized portion of the main pancreatic duct was seen, along with improvement of the bile duct stenosis. Pancreatic enlargement decreased, and the abnormal signal intensity on both T1- and T2-weighted MR images became isointense. CONCLUSION: MRCP cannot differentiate irregular narrowing of the main pancreatic duct seen with AIP from stenosis of the main pancreatic duct seen with pancreatic carcinoma. However, MRCP findings in conjunction with MR imaging of pancreatic enlargement that shows abnormal signal intensity on T1- and T2-weighted MR images are useful in supporting a diagnosis of AIP.

Autoimmune Diseases↗
PubMed2006

Usefulness of biopsying the major duodenal papilla to diagnose autoimmune pancreatitis: a prospective study using IgG4-immunostaining.

AIM: To examine the histological and immunohistochemical findings of biopsy specimens taken from the major duodenal papilla of autoimmune pancreatitis (AIP) patients. METHODS: The major duodenal papilla in the resected pancreas of 3 patients with AIP and of 5 control patients [pancreatic carcinoma (n = 3) and chronic alcoholic pancreatitis (n = 2)] was immunostained using anti-CD4-T cell, CD8-T cell and IgG4 antibodies. Forceps biopsy specimens taken from the major duodenal papilla of 2 patients with AIP and 5 control patients with suspected papillitis were prospectively taken during duodenoscopy and immunohistochemically examined. RESULTS: Moderate or severe lymphoplasmacytic infiltration including many CD4-positive or CD8-positive T lymphocytes and IgG4-positive plasma cells (>or=10/HPF), was observed in the major duodenal papilla of all 3 patients with AIP. The same findings were also detected in the biopsy specimens taken from the major duodenal papilla of 2 patients with AIP, but in controls, there were only a few (<or=3/HPF) IgG4-positive plasma cells infiltrating the major duodenal papilla. CONCLUSIONS: An abundant infiltration of IgG4-positive plasma cells is specifically detected in the major duodenal papilla of patients with AIP. Although this is a preliminary study, IgG4-immunostaining of biopsy specimens taken from the major duodenal papilla may support the diagnosis of AIP.

Aged↗
PubMed2006

Involvement of pancreatic and bile ducts in autoimmune pancreatitis.

AIM: To examine the involvement of the pancreatic and bile ducts in patients with autoimmune pancreatitis. METHODS: Clinical and cholangiopancreatographic findings of 28 patients with autoimmune pancreatitis were evaluated. For the purposes of this study, the pancreatic duct system was divided into three portions: the ventral pancreatic duct; the head portion of the dorsal pancreatic duct; and the body and tail of the dorsal pancreatic duct. RESULTS: Both the ventral and dorsal pancreatic ducts were involved in 24 patients, while in 4 patients only the dorsal pancreatic duct was involved. Marked stricture of the bile duct was detected in 20 patients and their initial symptom was obstructive jaundice. Six patients showed moderate stenosis to 30%-40% of the normal diameter, and the other two patients showed no stenosis of the bile duct. Although marked stricture of the bile duct was detected in 83% (20/24) of patients who showed narrowing of both the ventral and dorsal pancreatic ducts, it was not observed in the 4 patients who showed involvement of the dorsal pancreatic duct alone (P=0.0034). CONCLUSION: Both the ventral and dorsal pancreatic and bile ducts are involved in patients with autoimmune pancreatitis.

Aged↗
PubMed2006

Autoimmune pancreatitis: proposal of IgG4-related sclerosing disease.

Autoimmune pancreatitis (AIP) is a peculiar type of pancreatitis of presumed autoimmune etiology. Many new clinical aspects of AIP have been clarified during the past 10 years, and AIP has become a distinct entity recognized worldwide. However, its precise pathogenesis or pathophysiology remains unclear. As AIP dramatically responds to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary surgery. Characteristic dense lymphoplasmacytic infiltration and fibrosis in the pancreas may prove to be the gold standard for diagnosis of AIP. However, since it is difficult to obtain sufficient pancreatic tissue, AIP should be diagnosed currently based on the characteristic radiological findings (irregular narrowing of the main pancreatic duct and enlargement of the pancreas) in combination with serological findings (elevation of serum gamma-globulin, IgG, or IgG4, along with the presence of autoantibodies), clinical findings (elderly male preponderance, fluctuating obstructive jaundice without pain, occasional extrapancreatic lesions, and favorable response to steroid therapy), and histopathological findings (dense infiltration of IgG4-positive plasma cells and T lymphocytes with fibrosis and obliterative phlebitis in various organs). It is apparent that elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells into various organs are rather specific to AIP patients. We propose a new clinicopathological entity, "IgG4-related sclerosing disease", and suggest that AIP is a pancreatic lesion reflecting this systemic disease.

Autoimmune Diseases↗
PubMed2006

Alveolar echinococcosis of the liver in a Tokyo resident with an unknown route of infection: report of a case.

We report the case of a 45-year-old Tokyo man who developed alveolar echinococcosis of the liver, which is an extremely rare disorder in Japan, except for Hokkaido, Japan's northernmost island. The findings of multiple clustered cysts on computed tomography were unlike those of any hepatic tumors we had previously encountered. T2-weighted magnetic resonance imaging revealed the characteristic findings of small cysts with a very high signal intensity. The tumors were successfully removed by a hepatic resection. The patient lives in Tokyo, but has visited Hokkaido many times. The exact route of infection in this patient remains unclear. Sliced raw venison, which he reported eating on every visit to Sapporo in Hokkaido, represented the only potential route of infection we could identify. This meat may have somehow become contaminated with embryonated eggs. Nowadays, even city inhabitants are at risk of developing rare diseases due to the rapid development of transportation systems.

Diet↗
PubMed2006

Clinicopathologic features of ampullary carcinoma without jaundice.

GOALS: To evaluate clinicopathological features of ampullary carcinoma without jaundice. BACKGROUND: : Obstructive jaundice is the most common symptom of patients with ampullary carcinoma. However, some patients with ampullary carcinoma do not have jaundice at the time of diagnosis. STUDY: Clinicopathologic findings of 23 patients with ampullary carcinoma showing no visible jaundice (serum total bilirubin <3.0 mg/dL) and 38 patients with ampullary carcinoma showing jaundice at the time of diagnosis were retrospectively compared. RESULTS: Fifteen of 23 patients with nonjaundiced ampullary carcinoma complained of fever and/or abdominal pain. Five asymptomatic patients were found to have a dilated bile duct on screening ultrasound or to have a tumor-like swelling of the papilla of Vater during routine upper gastrointestinal endoscopy. There was no significant difference in age, sex, size, macroscopic type, histologic type, rates of duodenal invasion, pancreatic invasion, and lymph node metastasis, and prognosis between the two groups. The cumulative 5-year and 10-year survival rates of nonjaundiced patients were 70.2% and 49.0%, compared with 33.6% and 29.4% of jaundiced patients. Ten of the 23 nonjaundiced ampullary carcinomas (43%) were in Stage I, whereas 4 of the 38 jaundiced ampullary carcinomas (11%) were in Stage I (P < 0.01). Mechanisms of nonjaundice in ampullary carcinoma were suspected to be determinant by the infiltrating pattern of the carcinoma to the lower portion of the bile duct. CONCLUSIONS: Mechanisms of nonjaundice in ampullary carcinoma might be determined by the infiltrating pattern of the carcinoma to the lower portion of the bile. As a greater number of nonjaundiced ampullary carcinomas were in an early stage, detection of them may provide an improved clinical outcome.

Aged↗
PubMed2006

[Low-dose gemcitabine concurrent with radiation therapy for locally advanced pancreatic carcinoma].

We evaluated the efficacy and feasibility of low-dose gemcitabine concurrent with radiation as adjuvant therapy. Nine cases of locally far advanced unresectable pancreatic cancer were enrolled in this study. Intraoperative radiation was carried out in every case using eight or ten centimeter cones with a radiation dose of twenty to twenty five Gy. Postoperative radiation was two Gy per day on weekdays for five weeks. Low-dose gemcitabine (40 mg/m2) once a week was administered prior to radiation. A grade 3 adverse event occurred in three cases. CA19-9 decreased 60.1% and DUPAN-2, 52.6%. CT scan confirmed a necrotic change and a decrease of the tumor size. Average survival time was ten months. Peritoneal dissemination was the recurrence pattern. In conclusion, low-dose gemcitabine concurrent with radiation therapy may contribute to local control of the disease. However, peritoneal dissemination must be overcome to prolong survival.

Antigens, Neoplasm↗
PubMed2005

Malignancies associated with intraductal papillary mucinous neoplasm of the pancreas.

AIM: As intraductal papillary mucinous neoplasm (IPMN) has a favorable prognosis, associated malignancies have potential significance in these patients. We examined the incidence and characteristics of pre-existing, coexisting and subsequent malignancies in patients with IPMN. METHODS: Seventy-nine cases of IPMN were diagnosed by detection of mucous in the pancreatic duct during endoscopic retrograde pancreatography. Histological diagnosis was confirmed in 30 cases (adenoma (n = 19) and adenocarcinoma (n = 11). Other primary malignancies associated with IPMN, occurring in the prediagnostic or postdiagnostic period, were investigated. Postdiagnostic follow-up period was 3.3+/-0.5 years (range, 0.2-20 years). RESULTS: Other 40 malignancies occurred in 28 patients (35%). They were found before (n = 15), at (n = 19) and after (n = 6) the diagnosis of IPMT. Major associated malignancies were gastric cancer (n = 12), colonic cancer (n = 7), esophageal cancer (n = 4), pulmonary cancer (n = 4), and independent pancreatic cancer (n = 3). Pancreatic cancer was synchronous with IPMN in two patients and metachronous in one (3 years after diagnosis of IPMN). Thirty-one lesions were treated surgically or endoscopically. Fourteen patients died of associated cancers. Development of other malignancies was related to age (71.9+/-8.2 vs 66.8+/-9.3, P<0.05), but not to gender or site of the tumor. CONCLUSION: IPMN is associated with a high incidence of other malignancies, particularly gastric and colonic cancers. Common genetic mechanisms between IPMN and other associated malignancies might be present. Clinicians should pay attention to the possibility of associated malignancies in preoperative screening and follow-up of patients with IPMN.

Adenocarcinoma, Mucinous↗
PubMed2005

Thermo-chemo-radiotherapy for advanced bile duct carcinoma.

AIM: Complete resection of the bile duct carcinoma is sometimes difficult by subepithelial spread in the duct wall or direct invasion of adjacent blood vessels. Nonresected extrahepatic bile duct carcinoma has a dismal prognosis, with a life expectancy of about 6 mo to 1 year. To improve the treatment results of locally advanced bile duct carcinoma, we have been conducting a clinical trial using regional hyperthermia in combination with chemoradiation therapy. METHODS: Eight patients complaining of obstructive jaundice with advanced extrahepatic bile duct underwent thermo-chemo-radiotherapy (TCRT). All tumors were located in the upper bile duct and involved hepatic bifurcation, and obstructed the bile duct completely. Radiofrequency capacitive hyperthermia was administered simultaneously with chemotherapeutic agents once weekly immediately following radiotherapy at 2 Gy. We administered heat to the patient for 40 min after the tumor temperature had risen to 42 degrees C. The chemotherapeutic agents employed were cis-platinum (CDDP, 50 mg/m(2)) in combination with 5-fluorouracil (5-FU, 800 mg/m(2)) or methotrexate (MTX, 30 mg/m(2)) in combination with 5-FU (800 mg/m(2)). Number of heat treatments ranged from 2 to 8 sessions. The bile duct at autopsy was histologically examined in three patients treated with TCRT. RESULTS: In respect to resolution of the bile duct, there were three complete regression (CR), two partial regression (PR), and three no change (NC). Mean survival was 13.2+/-10.8 mo (mean+/-SD). Four patients survived for more than 20 mo. Percutaneous transhepatic biliary drainage (PTBD) tube could be removed in placement of self-expandable metallic stent into the patency-restored bile duct after TCRT. No major side effects occurred. At autopsy, marked hyalinization or fibrosis with necrosis replaced extensively bile duct tumor and wall, in which suppressed cohesiveness of carcinoma cells and degenerative cells were sparsely observed. CONCLUSION: Although the number of cases is rather small, TCRT in the treatment of locally advanced bile duct carcinoma is promising in raising local control and thus, long-term survival.

Aged↗
PubMed2005

Treating patients with autoimmune pancreatitis: results from a long-term follow-up study.

BACKGROUND: Steroid therapy is currently common treatment for autoimmune pancreatitis (AIP); however, indications of steroid therapy have yet to be established, and the clinical course after steroid therapy is unknown. METHODS: A total of 23 patients with AIP were subdivided into 4 groups according to the initial treatments undertaken. They were treated with pancreatoduodenectomy on suspicion of pancreatic tumor in 6 patients, choledochoduodenostomy with pancreatic biopsy in 4 patients, supportive therapy in 3 patients, and steroid therapy in 10 patients. Clinical course of AIP in each group was examined. RESULTS: Prognosis of the AIP patients is almost good except for the 2 patients who progressed to pancreatic insufficiency after resection. Two patients without jaundice improved spontaneously. Steroid therapy was effective in all patients treated, but pancreatic atrophy developed in 5 of these patients. Steroid therapy improved insulin secretion and glycemic control in 4 of 7 diabetes mellitus (DM) patients. CONCLUSION: To avoid futile surgery, in relatively elderly male patients with obstructive jaundice suggestive of pancreatic carcinoma, preoperative clinical suspicion of AIP is mandatory. Indications of steroid therapy for AIP are thought to be obstructive jaundice due to stenosis of the bile duct, other associated systemic autoimmune, and DM coincidental with AIP.

Adult↗
PubMed2005

Pancreatographic findings in idiopathic acute pancreatitis.

BACKGROUND/PURPOSE: Despite extensive evaluation based on clinical history, biochemical tests, and noninvasive imaging studies, the cause of acute pancreatitis cannot be determined in 10 to 30% of patients, and a diagnosis of idiopathic acute pancreatitis is made. The purpose of this study was to clarify the pancreatographic findings in patients with idiopathic acute pancreatitis. METHODS: Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 34 patients with idiopathic acute pancreatitis, and the pancreatographic findings were examined. Patency of the accessory pancreatic duct was examined by dye-injection endoscopic retrograde pancreatography (ERP) in 16 of the 34 patients. RESULTS: In 11 patients (32%), the following anatomic abnormalities of the pancreatic or biliary system were demonstrated: complete pancreas divisum (n = 5), incomplete pancreas divisum (n = 2), high confluence of pancreaticobiliary ducts (n = 2), choledochocele (n = 1), and giant periampullary diverticulum (n = 1). Pancreatographic findings were normal in 17 patients. Eleven of these patients were examined by dye-injection ERP, and all were found to have nonpatent accessory pancreatic duct. CONCLUSIONS: Anatomic abnormality of the pancreatic or biliary system is one of the major causes of idiopathic acute pancreatitis. Closure of the accessory pancreatic duct may play a role in the development of idiopathic acute pancreatitis in patients with a normal pancreaticobiliary ductal system.

Acute Disease↗