Biomedical subjects

S Kitano

Publications and source records attributed to S Kitano.

At least 91 records · Page 5Linked to original sources

PubMed1999

Immunohistochemical expression of cytokeratins in intrahepatic cholangiocarcinoma and metastatic adenocarcinoma of the liver.

BACKGROUND AND OBJECTIVES: This study was designed to identify a difference in immunostaining that might help to distinguish between primary and metastatic liver neoplasms. METHODS: We examined immunohistochemical expression of cytokeratins (CKs) 7, 8, 19, and 20 in 12 intrahepatic cholangiocarcinomas (ICCs; 9 of the mass-forming and 3 of the infiltrating type), 25 metastatic colorectal carcinomas (MCCs), and 7 metastatic gastric carcinomas (MGCs) of the liver. RESULTS: CKs 7 and 19 were expressed in all ICCs of infiltrating type, while each was seen in 7/9 (77.8%) of mass-forming type. CK 7-positive/CK 20-negative was seen in 9/12 (75.0%) of ICCs and in none of the 25 MCCs, while CK 7-negative/CK 20-positive was seen in 1/12 (8.3%) of ICCs and 20/25 (80.0%) of MCCs. No differences were observed between MGCs and ICCs. CONCLUSIONS: These results suggest that immunohistochemical staining for both CKs 7 and 20 is useful for the differential diagnosis of ICCs and MCCs, whereas phenotypic expression of CKs appears to be different between mass-forming and infiltrating types of ICCs.

Adenocarcinoma↗

PubMed1999

Histopathologic characteristics of colorectal cancer with liver metastasis.

PURPOSE: Although prognostic factors of colorectal cancer have been studied, factors associated with liver metastasis have not been fully investigated. The aim of this study was to clarify the histopathologic characteristics of colorectal cancer with liver metastasis. METHODS: We performed a retrospective histopathologic study on 335 patients who underwent resection of colorectal cancer during 15 years. Histopathologic parameters of tumors with liver metastasis were compared with those without liver metastasis. RESULTS: Forty-one patients (12 percent) had simultaneous liver metastasis. Tumors having liver metastasis, when compared with those not having liver metastasis, were characterized by high frequency of tumor size more than 6 cm (51 vs. 28 percent; P < 0.01), presence of serosal invasion (98 vs. 66 percent; P < 0.01), lymphatic invasion (34 vs. 15 percent; P < 0.01), venous invasion (24 vs. 3 percent; P < 0.01), and lymph node metastasis (85 vs. 39 percent; P < 0.01). Multivariate analysis showed that factors independently associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Accuracy in the diagnosis of liver metastasis was highest for venous invasion (88 percent) and lowest for serosal invasion (41 percent). Among 98 patients with both serosal invasion and lymph node metastasis, tumors with and without liver metastasis were different in frequency of venous invasion (26 vs. 6 percent; P < 0.01) and extracolic lymph node metastasis (68 vs. 47 percent; P < 0.05). CONCLUSION: In colorectal cancer important factors associated with liver metastasis were serosal invasion, venous invasion, and lymph node metastasis. Significant determinants for liver metastasis from colorectal cancer were venous invasion and extracolic lymph node metastasis.

Adenocarcinoma↗

PubMed1999

Laparoscopic resection for ectopic gastric mucosa of the duodenum: report of a case.

We report herein the case of a 53-year-old man in whom ectopic gastric mucosa was successfully resected laparoscopically. Radiography and endoscopy showed a well-demarcated and sessile polypoid lesion measuring 2.0 cm in diameter in the second part of the duodenum. Under the diagnosis of a submucosal tumor of the duodenum, a wedge resection of the duodenum was performed laparoscopically. Subsequent histological examination revealed that the tumor was ectopic gastric mucosa of the duodenum.

Choristoma↗

PubMed1999

A laparoscopic pull-through operation for Hirschsprung's disease: report of two infant cases.

We describe herein a primary laparoscopic pull-through procedure that was successfully employed to treat two infants with Hirschsprung's disease. Mobilization of the rectum and sigmoid colon was performed laparoscopically, and the rectal mucosa was removed via a transanal submucosal resection. After inducing the rectal prolapse intussusceptically, the rectum was circumferentially transected, and the mobilized colon was pulled down through the rectal muscle cuff. Resection of the aganglionic bowel and the coloanal anastomosis, using the Soave-Denda method, was performed outside the anus. Both infants had an uneventful postoperative course with early recovery of bowel movement. Our experience demonstrates that this minimally invasive surgical procedure is feasible for young infants, and we believe that Hirschsprung's disease may be a definite indication for laparoscopic surgery.

Colon, Sigmoid↗

PubMed1999

Laparoscopic-assisted proximal gastrectomy for early gastric carcinomas.

Laparoscopic-assisted proximal gastrectomy was performed in two Japanese patients with early gastric carcinomas located in the gastric cardia. The lower esophagus and upper stomach was divided under the pneumoperitoneum and resected via a minilaparotomy through an incision, 5 cm long, made in the epigastric area. The distal esophagus was anastomosed to a gastric tube made by resecting the lesser curvature of the stomach with a linear auto-stapler. Both patients recovered quickly without any postoperative complications, such as esophagitis, developing during follow-up periods of 3 and 6 months, respectively. Thus, we conclude that laparoscopic-assisted proximal gastrectomy and reconstruction with a gastric tube may be an effective method of treatment for patients with early gastric carcinomas located in the upper stomach in this era of minimally invasive surgery.

Cardia↗

PubMed1999

Clinicopathologic study of gastric cancer based on Dukes' classification.

Dukes' classification is a useful staging system in patients with colorectal cancer. The aim of this study was to present clinicopathologic characteristics and survival of patients with gastric cancer based on Dukes' classification. A total of 273 patients with gastric cancer curatively treated by radical gastrectomy and lymph node dissection (D2, D3) were studied. With the modified Dukes' classification, A includes tumors limited to the mucosa, submucosa, or muscularis propria; B includes tumors extending into the subserosa or serosa; Ca includes tumors with one to six positive lymph nodes; and Cb includes tumors with seven or more positive lymph nodes. Dukes' classification modified by the number of positive lymph nodes well correlated with the tumor size (p < 0.01), depth of wall invasion (p < 0.01), level of lymph node metastasis (p < 0.01), and degree of lymphatic permeation (p < 0.01) and venous permeation (p< 0.01). The 5-year survival rate was significantly different among Dukes' A (98%), Dukes' B (90%), Dukes' Ca (75%), and Dukes' Cb (44%) cases. The results indicate that Dukes' classification modified by the number of positive lymph nodes (Dukes' A, B, Ca, an Cb) significantly correlates with tumor progression and patient survival; and it may be a simple and useful staging system for gastric cancer.

Adenocarcinoma↗

PubMed1999

Laparoscopic resection of a pancreatic mucinous cystadenoma using laparosonic coagulating shears.

A 71-year-old woman with a solitary mucinous cystic neoplasm of the pancreatic tail complained of back pain. A laproscopic distal pancreatectomy was performed. Laparosonic coagulating shears (LCS) were employed for dissection of the surrounding tissue and transection of the pancreas. The main pancreatic duct was clipped. There was no evidence of bleeding or pancreatic leakage from the transection surface. Pathologic examination showed the tumor to be a mucinous cystadenoma. The postoperative course was uneventful. The LCS was effective in this application.

Aged↗

PubMed1999

Amelioration of tumor necrosis factor release by cyclosporine in warm ischemia/reperfusion injury of the rat liver: with special reference to hepatic ultrastructure.

Mechanisms by which an immunosuppressant (cyclosporine, CsA) ameliorates warm ischemic injury of the liver were studied. Female Sprague-Dawley rats were subjected to 60-min normothermic liver ischemia. Animals were assigned to one of two groups: group I, controls with vehicle treatment; group II, treatment with CsA (10 mg/kg). CsA was given orally for 4 consecutive days prior to the induction of hepatic ischemia. In addition to a survival study, plasma levels of endotoxin, serum activity of tumor necrosis factor-alpha (TNF), and serum levels of aminotransferases were measured in blood samples collected from the suprahepatic vena cava, and hepatic ultrastructural alterations were examined under an electron microscope. The 7-day survival rate was significantly higher in the CsA-treated animals. In the control group, serum TNF levels were elevated following reperfusion and peaked at 3 h. When the values at 3 h post reflow were compared, the animals given CsA had significantly lower levels of TNF (170.0 +/- 30.5 pg/ml for group I, 67.6 +/- 13.7 for group II, mean +/- SEM; P < 0.05). The sinusoidal lining cells and hepatocytes were drastically destroyed at 6 h post reflow in the control group, although the degree of injury at 1-3 h was less severe. On the other hand, the endothelium and parenchymal liver cells in the CsA-treated group were well preserved at 6 h in comparison with those in the control group. Our data suggest that modulation of TNF production is one of the mechanisms through which CsA prevents the exacerbation of ischemia/reperfusion injury of the liver.

Animals↗

PubMed1999

Expansive suboccipital cranioplasty for the treatment of syringomyelia associated with Chiari malformation.

In order to treat syringomyelia associated with adult type Chiari malformation, the authors developed a method of expansive suboccipital cranioplasty (ESC) that involves enlarging the small posterior fossa to obtain a sufficient flow of cerebrospinal fluid (CSF). The relative effectiveness of ESC with the obex plugged and not plugged was also examined, as well as other factors influencing the operative results. Twenty patients without arachnoid adhesion at the major cistern underwent ESC without opening the arachnoid membrane at the major cistern. After surgery, all improved with no recurrence and CSF flow study using magnetic resonance (MR) imaging showed significant improvement of the flow at the major cistern. Another 20 patients without arachnoid adhesion also underwent ESC but with obex plugging. Sixteen improved and one displayed only temporary improvement with recurrent syringomyelia due to postoperative arachnoid adhesions. The remaining three showed no change in spite of shrinkage of the syrinx on postoperative MR imaging. These three patients had displayed pre-operative symptoms over an approximately 10-year period involving almost the entire axial plain of the spinal cord, and presented a large syrinx before surgery. In 4 patients with arachnoid adhesions, all required intra-arachnoid procedures in addition to ESC. Intra-arachnoid procedures are not necessary to facilitate restoration of CSF flow in patients without arachnoid adhesions, because ESC can release the CSF flow blockage in the major cistern even without plugging of the obex. An associated arachnoid adhesion at the major cistern or a long-standing syringomyelia with irreversible damage of the spinal cord results in a poor operative prognosis. When posterior fossa surgery fails, insufficient decompression or postoperative arachnoid adhesions at the major cistern as the cause of treatment's failure should be evaluated by CSF flow studies using phase contrast MR imaging.

Adult↗

PubMed1999

Histopathologic criteria for local excision of colorectal cancer: multivariate analysis.

BACKGROUND: Local treatment of colorectal cancer, including endoscopic removal of colonic polyps and transanal resection of rectal tumors, has become widely accepted. However, risk factors predicting the presence of lymph node metastasis have not been fully investigated. To determine the criteria for local excision of colorectal cancer, histopathologic factors independently predicting the lymph node metastasis were investigated. METHODS: We performed a retrospective histopathologic study on 335 patients who underwent resection of colorectal cancer and dissection of regional lymph nodes between 1982 and 1996. Features of node-positive tumors (n = 150) were compared with those of node-negative tumors (n = 185), with special reference to the histopathologic findings of the resected tumor. Multivariate analysis was done using the stepwise logistic regression test. RESULTS: Node-positive tumors, when compared with node-negative tumors, were characterized by tumor larger than 6 cm (42% vs. 22%), serosal invasion (88% vs. 56%), lymphatic invasion (32% vs. 5%), venous invasion (9% vs. 2%), and histology other than well-differentiated (66% vs. 29%). Multivariate analysis showed that factors independently associated with lymph node metastasis were serosal invasion, lymphatic invasion, and histologic type. When these three risk factors were negative, lymph node metastasis was rare (5%). When one, two, or three factors were positive, the frequency of lymph node metastasis was 38%, 66%, and 85%, respectively. CONCLUSIONS: In colorectal cancer, factors independently associated with lymph node metastasis are serosal invasion, lymphatic invasion, and histologic type. When these three parameters are favorable, local treatment of colorectal cancer does not require additional lymph node dissection.

Colorectal Neoplasms↗

PubMed1999

Segment VIII resection of the cirrhotic liver under continuous pringle maneuver with in situ cooling followed by temporary portal decompression.

Successful segment VIII resection under continuous Pringle maneuver has been performed on a cirrhotic patient, using a new technique that combined the methods of in situ liver cooling and subsequent temporary decompression of the portal system. This procedure prevents the major drawbacks of the Pringle maneuver: the ischemic injury of the liver and the abdominal visceral venous stagnation, particularly when performed on the patient with chronic liver disease.

Carcinoma, Hepatocellular↗

PubMed1999

The role of nitric oxide in the inhibition of gastric epithelial proliferation in portal hypertensive rats.

BACKGROUND/AIM: Portal hypertension is associated with inhibition of gastric epithelial proliferation and increased gastric nitric oxide synthase activity. Whether the nitric oxide inhibits gastric epithelial proliferation is unclear. METHODS: Portal vein ligation was performed to induce portal hypertension in rats. The rats were treated for 7 days with either vehicle or N(G)-nitro-L-arginine methyl ester (L-NAME) at 5 mg/kg or 25 mg/kg doses (gastric gavage, twice a day). Sham-operated rats treated with vehicle served as controls. Hemodynamic parameters were measured using radiolabeled microspheres in anesthetized animals. Gastric epithelial proliferation was assessed by evaluating the proliferative cell nuclear antigen labeling index. RESULTS: The cardiac index and gastric fundic blood flow were higher, and the gastric fundic proliferative cell nuclear antigen labeling index was lower in the portal hypertensive rats than in the controls. In portal hypertensive rats, the 5 mg/kg dose of L-NAME decreased the cardiac index and increased the gastric fundic proliferative cell nuclear antigen labeling index to levels similar to those found in the controls, but did not affect gastric fundic blood flow significantly. The 25 mg/kg dose of L-NAME further decreased both the cardiac index and the gastric fundic blood flow, but did not affect the gastric proliferative cell nuclear antigen labeling index significantly. CONCLUSIONS: In portal hypertensive rats, the correction of systemic hyperdynamic circulation by NO inhibition is associated with normalization of gastric epithelial proliferation. Excessive nitric oxide may inhibit gastric epithelial proliferation in portal hypertension.

Animals↗

PubMed1999

Carcinoma of the gallbladder associated with anomalous junction of the pancreaticobiliary duct in adults.

BACKGROUND: Anomalous junction of the pancreaticobiliary duct (AJPBD) is a congenital anomaly in which the junction is located outside the sphincter of Oddi. A high incidence of gallbladder carcinoma (GBC) has been reported in adult patients with AJPBD. STUDY DESIGN: Fourteen adult patients with AJPBD and 50 with GBC not associated with AJPBD were reviewed retrospectively to identify the clinical characteristics of AJPBD accompanied by GBC and to clarify the differences in clinicopathologic features between GBC associated with AJPBD and GBC without AJPBD. RESULTS: Among the 14 patients with AJPBD, there were five fusiform, four cystic, and two cylindric dilatations of the biliary tract and three nondilated bile ducts. Nine (64%) of 14 patients had GBC, five with fusiform dilatations, two with cylindric dilatations, and two with nondilated bile ducts. No patient with cystic dilatation had GBC. There were two stage I cancers, four stage II, two stage III, and one stage IVB. One patient with stage IVB GBC died of recurrence 8 months after operation. The remaining 8 patients were well without signs of recurrence from 8 to 72 months after operation. The frequency of grossly polypoid or histologically papillary adenocarcinoma was higher in GBC patients with AJPBD than in those without AJPBD (p < 0.01). The proportion of disease-free survivors was greater among GBC patients with AJPBD than among those without AJPBD (p < 0.05). CONCLUSIONS: AJPBD with noncystic dilatation or without dilatation appears to be an important risk factor for GBC. In this limited series, patients with GBC accompanied by AJPBD have had relatively favorable outcomes.

Adult↗

PubMed1999

Impaired adaptive cytoprotection to ethanol-induced damage in gastric mucosa of portal hypertensive rats.

Portal hypertension predisposes gastric mucosa to increased damage by noxious agents. Adaptive cytoprotection has not been studied in portal hypertensive gastric mucosa. We evaluated adaptive cytoprotection in the gastric mucosa of portal hypertensive rats by exposure to ethanol. The injury index (percent gross lesions) was significantly higher in portal hypertensive rats than in sham-operated rats. The ratio of adaptive cytoprotection, calculated as the degree of decrease in the injury index caused by pre-absolute-ethanol administration of 20% ethanol, was significantly impaired in portal hypertensive rats. Basal levels of gastric mucosal hexosamine were lower in portal hypertensive rats than in controls, and a blunted response to 20% ethanol was associated with portal hypertension. Nitric oxide inhibition (L-NAME, 5 mg/kg) reduced the ratio of adaptive cytoprotection in sham-operated but not in portal hypertensive rats. These results suggest that impaired adaptive cytoprotection in portal hypertensive gastric mucosa may be caused by blunted mucus production.

Adaptation, Physiological↗

PubMed1999

Indication for and outcome of laparoscopy-assisted Billroth I gastrectomy.

BACKGROUND: Since 1991, laparoscopy-assisted Billroth I gastrectomy has been used for patients with early gastric cancer. The aim of this study was to clarify the outcome of 40 patients who underwent this operation and to examine the indications based on a retrospective histological study of 248 resected cases of early gastric cancer. METHODS: Operating time, blood loss, length of skin incision, and postoperative hospital stay and complications were examined using the operation records and medical charts. The presence or absence of lymph node metastasis, tumour size, site, gross type, histological type, depth of invasion, presence or absence of ulceration, and status of lymph node metastasis were investigated in 248 early gastric cancers. RESULTS: The mean operating time was 3 h and 48 min and the mean length of skin incision was 5.8 cm. Although one patient who had suffered from chronic bronchitis developed pneumonia and wound dehiscence, no other patients had a postoperative complication. The mean hospital stay after operation was 16 days and all patients were alive without recurrence at a median follow-up of 21 months. The incidence of lymph node metastasis in early gastric cancer was 2 per cent (three of 130) in mucosal cancers and 14 per cent (17 of 118) in submucosal cancers. These lesions could have been completely resected by laparoscopy-assisted gastrectomy. CONCLUSION: All 40 patients were treated successfully by laparoscopy-assisted Billroth I gastrectomy without significant complications and with no recurrences to date. Pathological study of conventionally resected stomach and lymph nodes confirmed that laparoscopy-assisted Billroth I gastrectomy would be a safe and useful operation for most early gastric cancers.

Adult↗

PubMed1999

The fas and fas ligand pathways in liver allograft tolerance.

The Fas and Fas ligand (Fas/FasL) pathways may play a central role in cytotoxicity or immunoregulation in liver transplantation. Here, in an attempt to examine the role of Fas/FasL on drug-free tolerance, we measured mRNA levels of Fas/FasL in livers by reverse transcriptase-polymerase chain reaction (RT-PCR), and also protein levels of Fas/FasL in livers by immunohistochemistry and in serum by dot blot assay. PVG recipients bearing DA livers showed serious rejection between post-operative (POD) days 7 and 14, but this rejection was naturally overcome without any immunosuppression. Fas gene and protein products were expressed on almost every cell in livers taken from naive rats, and at any time point in both syngeneic and allogeneic orthotopic liver transplantation (OLT) rats. In contrast, FasL mRNA in DA livers was detectable at POD 2, peaked at POD 14, and declined at POD 63 in allogeneic OLT (DA-PVG). Although the FasL gene was detectable in isografts at POD 14, its expression was much lower than in allografts. The time course and localization of FasL expression indicated that the expression of FasL gradually switched from infiltrating cells to hepatocytes when the rejection was naturally overcome and tolerance was induced in this OLT model. Soluble Fas could constitutively be detected at any time point in the serum of the tolerogenic OLT (DA-PVG) rats and was not diminished during the rejection phase. Soluble FasL peaked at POD 14 in allogeneic OLT, while sFasL was significantly lower in the serum of normal and syngeneic OLT rats. These findings suggest that the Fas and FasL pathways, including soluble forms, may contribute to the control of the immune response in this drug-free tolerance OLT model.

Animals↗

PubMed1999

Diagnostic usefulness of endorectal magnetic resonance imaging with dynamic contrast-enhancement in patients with localized prostate cancer: mapping studies with biopsy specimens.

BACKGROUND: New diagnostic criteria for dynamic magnetic resonance (MR) imaging in prostate cancer are presented. The diagnostic usefulness of endorectal MR imaging with dynamic contrast-enhancement in localized prostate cancer and the validity of these criteria were evaluated. METHODS: Eighteen untreated patients who were suspected of localized prostate cancer were included in the study. They received endorectal dynamic MR imaging before systematic sextant needle biopsy. First. a mapping study with the findings of MR images and histopathology of biopsy specimens was performed in eight patients out of 18 to compare the difference in T2-weighted images with the endorectal coil and the body coil in the same individuals. Second, another mapping study was performed in all 18 patients by analyzing the findings of endorectal dynamic MR images. For the diagnosis of prostate cancer in MR imaging, we offered diagnostic criteria from our experience in addition to those in plain T2-weighted images from the literature. RESULTS: The overall diagnostic rates of endorectal dynamic MR imaging were 88.9% in accuracy, 100% in sensitivity, and 81.8% in specificity. In the comparison of the endorectal and body coils in T2-weighted images in eight patients, there was no difference in the diagnostic rates except for one more histopathologic false positive portion in endorectal MR imaging. In the second mapping study in 18 patients, the diagnostic rates were 92.6% in accuracy, 88.9% in sensitivity and 93.3% in specificity. Endorectal dynamic imaging raised the diagnostic sensitivity from 77.8 to 88.9%. CONCLUSION: The data demonstrated the validity of this diagnostic criteria and the diagnostic usefulness of endorectal dynamic MR imaging in localized prostate cancer.

Aged↗

PubMed1999

Quality of life after laparoscopy-assisted Billroth I gastrectomy.

OBJECTIVE: To evaluate the quality of life of patients who had undergone laparoscopy-assisted Billroth I gastrectomy (LAG) for cure of cancer. SUMMARY BACKGROUND DATA: In 1994, the authors reported the first case of LAG for early gastric cancer, and this approach quickly has been adopted by Japanese surgeons. However, little is known about the subjective clinical results of this less invasive surgery. METHODS: Quality of life was estimated using the 24-item questionnaire with a scoring system of 1, 2, and 3 and was compared between 41 consecutive patients with LAG and 35 with conventional open gastrectomy. All patients underwent Billroth I gastrectomy for early gastric cancer from January 1993 to July 1997 and were alive without recurrence. RESULTS: Patients who had undergone LAG were taking a normal diet (100%) with >66% of volume at each meal (90%), showed no decreased performance status (90%), and were satisfied with their surgical results (88%). Patients with LAG, when compared with open gastrectomy, showed significantly better results with regard to weight loss, difficulty in swallowing, heartburn and belch, early dumping syndrome, and total score. LAG was better accepted by the patients. CONCLUSIONS: Quality of life after Billroth I gastrectomy was significantly better in patients in whom a laparoscopic technique was used than in those who underwent a conventional method. LAG is less invasive and better accepted by patients and is the procedure of choice for the treatment of early gastric cancer.

Aged↗