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Yutaka Atomi

Publications and source records attributed to Yutaka Atomi.

At least 55 records · Page 3Linked to original sources
PubMed2003

High mobility group A1 is expressed in metastatic adenocarcinoma to the liver and intrahepatic cholangiocarcinoma, but not in hepatocellular carcinoma: its potential use in the diagnosis of liver neoplasms.

BACKGROUND: An increased level of high mobility group A (HMGA) gene/protein expression has been demonstrated to be associated with many human neoplasms originating from a variety of tissues. However, HMGA1 expression has not yet been studied in hepatic tumors. In this study, we analyzed HMGA1 expression in hepatic primary and metastatic tumors in order to verify whether determination of the HMGA1 expression level could provide any diagnostic advantages in the pathological diagnosis of hepatic tumors. METHODS: Twenty samples of hepatocellular carcinoma, 5 samples of intrahepatic cholangiocarcinoma, and 21 samples of metastatic adenocarcinoma to the liver (15 metastatic tumors from colorectal carcinoma and 6 metastatic tumors from pancreatic carcinoma) were analyzed immunohistochemically using an HMGA1-specific antibody. RESULTS: While no significant nuclear immunoreactivity was found in hepatocytes of non-neoplastic liver tissue, 40% (2/5) of intrahepatic cholangiocarcinomas, 53.3% (8/15) of metastatic lesions from colorectal carcinoma, and 100% (6/6) of metastatic lesions from pancreatic carcinoma showed positive immunoreactivity. In contrast, all 20 samples of hepatocellular carcinoma were negative for HMGA1 nuclear immunoreactivity. Thus, hepatocellular carcinoma represents the first case of malignant neoplasia in which HMGA1 expression is not induced, which presents a striking contrast to several previous studies demonstrating the significance of increased HMGA gene/protein levels in carcinogenesis and/or tumor progression. CONCLUSIONS: Based on these findings, we conclude that the HMGA1 protein level could serve as a potential diagnostic marker that may enable the differential diagnosis between hepatocellular carcinoma and intrahepatic cholangiocarcinoma or metastatic adenocarcinoma to the liver.

Bile Duct Neoplasms↗
PubMed2003

Clinical utility of grading criteria for submucosal invasion in the prognosis of T1 colorectal carcinomas.

BACKGROUND: The clinical utility of relative and absolute grading criteria for submucosal invasion in T1 colorectal carcinomas has been controversial. METHODS: In 51 T1 colorectal carcinomas, depth of submucosal invasion was graded either according to a modified Haggitt's classification (a relative criterion) or by direct measurement using a micrometer (an absolute criterion), and immunostaining for E-cadherin, alpha-catenin, beta-catenin, matrilysin, and CD44 variant 6 was performed on formalin-fixed, paraffin-embedded sections. The associations between lymph node metastasis or local recurrence (locoregional failure) and tumor budding, and clinicopathologic parameters and immunoreactivity were examined statistically. RESULTS: By univariate analysis, tumor budding, histology, and the co-expression pattern of nuclear beta-catenin and CD44 variant 6 were significantly associated with locoregional failure. The relative and absolute grading of submucosal invasion were not significantly associated with locoregional failure. Multivariate analysis showed that tumor budding alone was significantly associated with locoregional failure, and the association between the co-expression pattern of nuclear beta-catenin and CD44 variant 6, and locoregional failure was marginally significant ( P = 0.0502). Lymphatic invasion and absolute grading of depth and width of submucosal invasion were significantly associated with tumor budding, and the associations between tumor budding, and histologic differentiation and membranous alpha-catenin expression were marginally significant ( P = 0.06; P= 0.08), whereas, a relative grading of submucosal invasion was not significant ( P = 0.58). Analysis of variance showed that histologic differentiation and lymphatic invasion were independently and significantly associated with tumor budding ( P = 0.005; P < 0.001). CONCLUSIONS: These results suggest that the grading of submucosal invasion, either relative or absolute, may not be a useful risk factor for lymph node metastasis or local recurrence in T1 colorectal carcinomas.

Adult↗
PubMed2003

Magnetic resonance cholangiopancreatography for postoperative follow-up of intraductal papillary-mucinous tumors of the pancreas.

BACKGROUND: After resection of an intraductal papillary-mucinous tumor (IPMT), benign tumors or portions of the resected tumor are sometimes left in place to avoid total pancreatectomy. We evaluated the role of magnetic resonance cholangiopancreatography (MRCP) in postoperative follow-up. METHODS: Twenty-two patients underwent MRCP 0.5 to 6.5 years after pancreatic resection for IPMT. RESULTS: Two patients with surgical margin involvement of the main pancreatic duct showed mildly enhanced ductal dilatation due to anastomotic stenosis. In 4 patients with residual IPMT of the branch ducts, postoperative MRCP demonstrated no changes. MRCP revealed new IPMT 1 year after surgery in 1 patient. No patients showed intraductal or intracystic mural nodules postoperatively. In 3 patients with postoperative pancreatitis or recurrent abdominal discomfort, MRCP demonstrated ductal dilatation and poor secretin-stimulated pancreatic secretion into the gastrointestinal tract, which suggested pancreatoenterostomic stenosis. CONCLUSIONS: MRCP is useful for postoperative follow-up of IPMT, in terms of investigating residual or recurrent IPMT and evaluating postpancreatectomy long-term complications.

Aged↗
PubMed2003

Comparison between endorectal coil and pelvic phased-array coil magnetic resonance imaging in patients with anorectal tumor.

BACKGROUND: Magnetic resonance imaging (MRI) has been used as one of the diagnostic tools in the preoperative evaluation of rectal cancer. However, the usefulness of endorectal coil (ERC) compared with phased array coil (PA) MRI is still unknown. PATIENTS AND METHODS: Nineteen patients with rectal (17 patients) and anal (2 patients) tumors undergoing both ERC-MRI and PA-MRI preoperatively were included in the study. Seventeen patients had advanced stage tumors, and the remaining 2 had early stage tumors. The diagnostic accuracy of depth tumor invasion and lymph node metastasis were compared with reference to the histopathologic findings as the gold standard. RESULTS: ERC-MRI was evaluable in only 10 (52.6%) of 19 patients, because of difficulties in ERC placement, whereas PA-MRI could be obtained in all patients (100%). In 10 patients examined by both modalities, the diagnostic accuracy of depth of tumor invasion was 80% by ERC-MRI and 80% by PA-MRI. In lymph node staging, ERC yielded sensitivity of 100%, specificity of 62.5%, and overall accuracy of 70.0%. The corresponding values for PA-MRI were 50%, 100% and 90.0%, respectively. These figures were not significantly different between the two modalities. CONCLUSIONS: ERC-MRI and PA-MRI showed similar diagnostic accuracy. ERC-MRI may be abandoned in the preoperative staging of patients with locally advanced anorectal tumors because of its limited clinical utility.

Adult↗
PubMed2003

A prospective comparison between multidetector-row computed tomography and magnetic resonance imaging in the preoperative evaluation of rectal carcinoma.

BACKGROUND: Multidetector-row computed tomography (MDCT, or multislice CT) is a new modality with four detectors, which makes examination time shorter and produces higher resolution and multiplanar reformation of the images. Its diagnostic role in patients with rectal carcinoma has not been determined. METHODS: Twenty-one patients with rectal carcinoma were preoperatively examined by both MDCT and magnetic resonance imaging (MRI). Diagnostic accuracies of both modalities were compared regarding depth of tumor invasion and lymph node metastasis based on the pathologic findings. RESULTS: Both examinations detected all tumors. Regarding depth of tumor invasion, the concordance was 95.2% (20 of 21) for MDCT and 100% (21 of 21) for MRI. Regarding lymph node metastasis, the overall accuracy was 61.9% for MDCT and 70.0% for MRI. CONCLUSIONS: Multidetector-row computed tomography was equal to MRI in the preoperative local staging of rectal carcinoma.

Adenocarcinoma↗
PubMed2003

Laminin-5 gamma2 chain expression as a possible determinant of tumor aggressiveness in T1 colorectal carcinomas.

This study was undertaken to clarify the associations between laminin-5 y2 chain expression, and tumor budding and lymph node metastasis or local recurrence (locoregional failure) of 50 T1 colorectal carcinomas immunohistochemically. Fifteen (30%) of 50 lesions were positive for laminin-5 gamma2 chain expression. By univariate analysis, less histological differentiation (P = 0.02), nonpolypoid growth pattern (P = 0.03) and tumorbudding (P < 0.001) were associated with laminin-5 gamma2 chain positivity. By multivariate analysis, tumor budding alone was significantly associated with laminin-5 gamma2 chain positivity (P = 0.006), and correlation between nonpolypoid growth pattern and laminin-5 gamma2 chain positivity lost its significance (P = 0.09). Tumor budding (P = 0.004) and laminin-5 gamma2 chain expression (P = 0.001) were significantly associated with locoregional failure. Laminin-5 gamma2 chain expression may contribute to the formation of budding tumor cells at the invasive front, and immunostaining of this adhesion molecule may be useful in identifying high-risk patients for locoregional failure in T1 colorectal carcinomas.

Adenocarcinoma↗
PubMed2003

Coexpression of matrilysin and laminin-5 gamma2 chain may contribute to tumor cell migration in colorectal carcinomas.

We attempted to examine the correlation between matrilysin and laminin-5 gamma2 chain expression with reference to the number of dedifferentiation units along the entire invasive front (tumor budding). Immunostaining for hMMP-7 and laminin-5 gamma2 chain was performed in 50 T1 colorectal carcinomas, and immunoreactivity was evaluated at the invasive front of the tumor. On hematoxylin-eosin sections, the number of tumor budding was counted. The localization of matrilysin tended to be widespread compared with that of laminin-5 gamma2 chain. Matrilysin and laminin-5 gamma2 chain expression were positive in 28 (56%) and 15 (30%) tumors respectively. There was a significant correlation between matrilysin and laminin-5 gamma2 chain expression (P = 0.02). Matrilysin(+)/laminin-5 gamma2 chain(+) tumors had a significantly greater amount of tumor budding than matrilysin(-)/laminin-5 gamma2 chain(-) tumors (P = 0.003) or matrilysin(+)/laminin-5 gamma2 chain(-) tumors (P = 0.03). In conclusions, coexpression of matrilysin and laminin-5 gamma2 chain may contribute to tumor cell migration in colorectal carcinomas.

Adult↗
PubMed2003

Predictive factors for acute pancreatitis and hyperamylasemia after endoscopic papillary balloon dilation.

BACKGROUND: Although endoscopic papillary balloon dilation may result in acute pancreatitis or hyperamylasemia, the risk factors for these complications have not been well documented. Risk factors predictive of acute pancreatitis and hyperamylasemia after endoscopic papillary balloon dilation were retrospectively analyzed. METHODS: In 118 patients who underwent endoscopic papillary balloon dilation for choledocholithiasis, postendoscopic papillary balloon dilation acute pancreatitis and hyperamylasemia (at least 3-fold elevation) were investigated. A multivariate analysis was conducted for 20 potential risk factors related to clinical and procedure characteristics. RESULTS: Bile duct clearance was achieved in 113 patients. Early complications in the form of mild pancreatitis occurred in 7 patients (6%). Multivariate analysis identified history of acute pancreatitis as the only risk factor for postendoscopic papillary balloon dilation pancreatitis. Postendoscopic papillary balloon dilation hyperamylasemia occurred in 30 patients (25%). Multivariate analysis identified 4 independent risk factors for hyperamylasemia: an age of 60 years or less, previous pancreatitis, bile duct diameter 9 mm or less, and difficult bile duct cannulation. CONCLUSIONS: Endoscopic papillary balloon dilation is associated with a relatively low occurrence (6%) of pancreatitis but a high frequency (25%) of hyperamylasemia. The latter may represent pancreatic irritation or latent pancreatic injury. Particular care is necessary when endoscopic papillary balloon dilation is performed in younger patients, those with a history of pancreatitis, patients with a nondilated bile duct, and when cannulation is difficult.

Acute Disease↗
PubMed2003

Effect of bacterial flora on postimmunization gastritis following oral vaccination of mice with Helicobacter pylori heat shock protein 60.

In order to assess the efficacy of oral Helicobacter pylori heat shock protein 60 (HSP60) as a vaccine, protection against H. pylori infection in specific-pathogen-free (SPF) C57BL/6 and germfree (GF) IQI mice was examined. Prophylactic oral vaccination of these two strains of mice with either H. pylori HSP60 or Escherichia coli GroEL inhibited H. pylori colonization by 90 to 95% at 3 weeks postinfection (p.i.). However, these mice were only partially protected because bacterial loads increased in all animals at 10 weeks p.i. Anti-H. pylori HSP60 immunoglobulin G was detected in serum at 3 weeks p.i. in mice vaccinated with either H. pylori HSP60 or GroEL. Significant increases in the gastritis scores were observed only in SPF mice immunized with H. pylori HSP60. These results indicate that oral vaccination with H. pylori HSP60 has partial protective effects on subsequent H. pylori infection but also induces postimmunization gastritis. However, GF mice immunized with H. pylori HSP60 did not suffer from severe gastritis. Therefore, the presence of bacterial flora appears to contribute to the induction of postimmunization gastritis.

Administration, Oral↗
PubMed2003

[Pilot study of TS-1 combined with lentinan in patients with unresectable or recurrent advanced gastric cancer].

TS-1, an anticancer, antimetabolis agent, has shown clinically superior antitumor activity against unresectable advanced or recurrent gastric cancer (UARG). A biological response modifier, lentinan (LNT) prolonged the survival period of patients with UARG when combined with tegafur (FT). To assess the efficacy, the safety and prognostic factors of chemo-immunotherapy using TS-1, a FT derivative, and LNT, we conducted a multi-institutional pilot study in patients with UARG. Patients were treated with TS-1 at 80 mg/m2/day (bid) for 4-weeks, and LNT was given at 2 mg/body (i.v.) in a week, followed by a 2-week rest for 4 cycles. Twenty-two patients were entered from 4 institutes and 19 patients were eligible. The median survival time in eligible patients was 400 days. The incidence of hematological toxicity (grade 2 leukopenia), and non-hematological toxicity (grade 3 nausea or fatigue) was 5.3% (1/19) and no grade 4 toxicity was observed. The response ratio was 37.5% in 8 patients who had been administered the planned dose of TS-1. In subset analyses, the survival period of the patients with normal (< 500 micrograms/ml) serum immunosuppressive acidic protein level was significantly (p < 0.0001) better than that of the higher one. The survival period for those patients whose granulocytes/lymphocytes ratio was not more than 2 tended to be better. From the prolonged survival periods, chemo-immunotherapy using TS-1 combined with LNT would seem to have a benefit against UARG, and reduced toxicity. Future clinical trials are warranted to confirm its potency.

Aged↗
PubMed2003

[Laparoscopic repair of esophageal hiatal hernia].

Hiatal hernias are usually classified into three distinct types: type I, sliding hernia; type II, paraesophageal hernia; and type III, a combination of type I and II hernias. Presentation of type I hernia is so-called reflux symptoms, in contrast with the symptoms associated with mechanical obstruction of the herniated stomach in type II and III hernias. Surgical indications for type I hernia depend upon the severity of esophagitis. In type II and III hernias, severe symptoms and complications represent the chief indications for repair. Totally intrathoracic stomach hernias generally present such a risk of volvulus, strangulation, and perforation that surgery is indicated even in asymptomatic and uncomplicated cases. Although the pathophysiology is different, the Nissen procedure is the surgical procedure of choice for both types of hiatal hernia. Since the first report in 1993, the laparoscopic Nissen procedure has gained wide acceptance. We have so far experienced 26 cases of hiatal hernia, 18 of type I and 8 of type II and III hernias. We used the laparoscopic Nissen procedure in all cases. There were no conversions to the open procedure. Hiatal hernia recurred only in one case with a short esophagus preoperatively. The laparoscopic Nissen procedure is here to stay for the repair of hiatal hernias regardless of their type.

Adult↗
PubMed2002

Laparoscopic pancreatic cystgastrostomy.

BACKGROUND/PURPOSE: Internal drainage of acute pancreatic pseudocysts is indicated after the first 6 weeks of pseudocyst documentation. It is also indicated for symptomatic chronic pseudocysts 6 cm or more in diameter. When a pseudocyst is in close contact with the posterior wall of the stomach, it is best drained by pseudocyst gastrostomy. METHODS: Intragastric surgical techniques were used in 18 patients with retrogastric pseudocysts. Intragastric ports were successfully placed in all patients, and the presence of pseudocysts was confirmed by needle aspiration in 17. RESULTS: The intragastric approach was successful in 14 patients. In three cases a small abdominal would 8 cm in length was needed. The reasons for such conversion included uncontrollable bleeding from the cystic wall in two cases and a cystic wall in contact with, but not adherent to, the posterior gastric wall in one. Bleeding was controlled through a gastrotomy, and cystgastrostomy was performed. The wound required for conversion was much smaller than that needed for planned open surgery. These procedures are called laparoscopy-assisted cystgastrostomy. Good short- and long-term results were obtained. One patient, in whom the cystgastrostomy was too small, developed a cyst infection and underwent reoperation. Except for this case, no recurrence was observed, and no further treatment was needed. CONCLUSIONS: This experience demonstrates that cystgastrostomy with the intragastric surgical technique is a safe, less invasive procedure for effectively draining a retrogastric pseudocyst.

Adult↗
PubMed2002

Laparoscopic hepatobiliary and pancreatic surgery: an overview.

Although they are not widely employed, advanced laparoscopic hepatobiliary pancreatic (HBP) procedures can be performed. Laparoscopic common bile duct (CBD) exploration has gained wide acceptance, and endoscopic retro-grade cholangiopancreatography/endoscopic sphincterotomy (ERCP/ES) may become less important in the treatment of CBD stones. Choledochal cyst is another example that is suitable for laparoscopic treatment. It can be removed, and bilioenteric flow is reestablished laparoscopically. Simple cyst of the liver is an excellent indication for laparoscopic surgery. Cysts are unroofed, and recurrence is rare. Hydatid disease can also be treated laparoscopically. In liver resection, the use of laparoscopy is limited to wedge resection and left lateral segmentectomy at most. Laparoscopic staging for pancreatic cancer can demonstrate respectability in 90% of cases. This staging may obviate unnecessary laparotomy. Although laparoscopic Whipple is feasible, laparoscoic distal pancreatectomy is a realistic indication for pancreatic resection. Laparoscopic distal pancreatectomy may be indicated for cystic neoplasms of low-grade malignancy, and for islet cell tumors. When internal drainage is indicated, pseudocysts can be treated laparoscopically. If the cyst is located close to the posterior gastric wall, cystgastrostomy can also be achieved with an endoluminal surgical technique.

Biliary Tract Surgical Procedures↗
PubMed2002

Risk factors predictive of lymph node metastasis in depressed early gastric cancer.

BACKGROUND: This study was conducted to identify risk factors predictive of regional lymph node metastasis in depressed early gastric cancer and further to establish an objective criterion useful to indicate additional surgical treatment in cases in which submucosal tumor extension becomes evident by endoscopic mucosal resection (EMR). METHODS: Data from 276 patients surgically treated for depressed early gastric cancer were collected, and the relationship between the patient and tumor characteristics, and the lymph node metastasis was retrospectively evaluated by multivariate analysis. RESULTS: In the multivariate logistic regression model, female sex, a larger tumor size (20 mm or more), submucosal invasion, and presence of lymphatic vessel involvement were found to be independent risk factors for lymph node metastasis. Among 145 patients with submucosally invasive carcinoma, no lymph node metastasis was observed in patients who showed none of the other three risk factors, whereas 14.3% and 23.3% of patients with one and two of these factors had lymph node metastasis, respectively. The lymph node metastasis rate was calculated to be 86.7% in patients who had all three factors. CONCLUSIONS: Submucosal invasion, female sex, tumor size of 20 mm or more, and lymphatic vessel involvement were significantly and independently related to the presence of lymph node metastasis in depressed early gastric cancer. The positive number of the latter three risk factors is a simple criterion to indicate additional surgical treatment in cases with submucosal invasion revealed first by EMR.

Adult↗
PubMed2002

Pyogenic hepatic abscess with biliary communication.

BACKGROUND: The aims of this study were to compare the effectiveness of percutaneous drainage between pyogenic hepatic abscesses with and those without biliary communication and to evaluate the role of endoscopic biliary stent placement in the treatment of communicating abscesses. METHODS: Sixty-one patients with hepatic abscesses underwent percutaneous drainage. For communicating abscesses refractory to drainage alone, endoscopic biliary stenting was performed. RESULTS: After drainage, all patients showed improvement in their clinical condition and reduction in abscess size. Drainage alone completely cured abscesses in none of 10 patients with biliary communication and obstruction, in 3 of 10 with communication but without obstruction, and in 37 of 41 without communication. Endoscopic stenting was completely effective in all 7 patients with persistent discharge from a communicating abscess without biliary obstruction. CONCLUSIONS: Percutaneous drainage is less effective for communicating abscesses without biliary obstruction than for noncommunicating abscesses. Endoscopic biliary stenting is recommended, if drainage does not achieve a cure.

Bile Ducts, Intrahepatic↗
PubMed2002

Preoperative evaluation by magnetic resonance imaging in patients with bowel obstruction.

BACKGROUND: Bowel obstruction is a problematic condition because the main clinical issue is to determine whether emergency laparotomy or observation with a long tube is required. The recent development of imaging diagnostic modalities such as magnetic resonance imaging (MRI) is thought to be promising to support therapeutic decisions in patients with bowel obstruction. METHODS: Twenty-seven patients with bowel obstruction who underwent laparotomy were evaluated by plain x-ray film, computed tomography (CT) scan, and MRI preoperatively with regard to the presence or absence of bowel obstruction, and the site and cause of bowel obstruction. Diagnostic accuracies were compared among these radiological modalities. RESULTS: The presence of bowel obstruction was detected in 22 (81.5%) of 27 patients by plain abdominal x-ray film, in 24 (92.3%) of 26 patients by CT scan, and in 25 (92.6%) of 27 patients by MRI. The sites of obstruction were consistent with surgical findings in 25 (92.6%) of 27 patients by MRI, and in 15 (57.7%) of 26 patients by CT scan. The causes of bowel obstruction were accurately diagnosed by MRI in 25 (92.6%) of 27 patients, and in 23 (88.5%) of 26 patients by CT scan. CONCLUSIONS: MRI could identify the presence and the site and cause of bowel obstruction in most of the cases. MRI is assumed to be superior to CT scan in the preoperative diagnosis of bowel obstruction.

Adult↗