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N Hayakawa

Publications and source records attributed to N Hayakawa.

At least 37 records · Page 2Linked to original sources
PubMed2001

Lymph node metastasis from hilar cholangiocarcinoma: audit of 110 patients who underwent regional and paraaortic node dissection.

OBJECTIVE: To assess the status of the regional and paraaortic lymph nodes in hilar cholangiocarcinoma and to clarify the efficacy of systematic extended lymphadenectomy. SUMMARY BACKGROUND DATA: There have been no studies in which regional and paraaortic lymphadenectomies for hilar cholangiocarcinoma have been routinely performed. Therefore, the metastasis rates to the regional and paraaortic nodes, the mode of lymphatic spread, and the effect of extended lymph node dissection on survival remain unknown. METHODS: This study involved 110 patients who underwent surgical resection for hilar cholangiocarcinoma with lymph node dissection including both the regional and paraaortic nodes. A total of 2,652 nodes retrieved from the surgical specimens were examined microscopically. RESULTS: Of the 110 patients, 52 (47.3%) had no involved nodes, 39 (35.5%) had regional lymph node metastases, and 19 (17.3%) had regional and paraaortic node metastases. The incidence of positive nodes was significantly higher in the patients with pT3 disease than in those with pT2 disease. The pericholedochal nodes were most commonly involved (42.7%), followed by the periportal nodes (30.9%), the common hepatic nodes (27.3%), and the posterior pancreaticoduodenal nodes (14.5%). The celiac and superior mesenteric nodes were rarely involved. The 3-year and 5-year survival rates were 55.4% and 30.5% for the 52 patients without involved nodes, 31.8% and 14.7% for the 39 patients with regional node metastases, and 12.3% and 12.3% for the 19 patients with paraaortic node metastases, respectively. Of the 19 patients with positive paraaortic nodes, 7 had no macroscopic evidence of paraaortic disease on intraoperative inspection. The survival in this group was significantly better than in the remaining 12 patients. CONCLUSION: The paraaortic nodes and the regional nodes are frequently involved in advanced hilar cholangiocarcinoma. Whether extended lymph node dissection provides a survival benefit requires further study. However, the fact that long-term survival is possible despite pN2 or pM1 disease encourages the authors to perform an aggressive surgical procedure with extended lymph node dissection in selected patients with hilar cholangiocarcinoma.

Aorta↗
PubMed2001

Clinicopathological features of superficial spreading and nonspreading squamous cell carcinoma of the esophagus.

OBJECTIVES: Superficially spreading carcinoma of the esophagus, consisting mainly of intraepithelial carcinoma, is not as rare as was previously thought. Despite the surgical significance of this entity, no general definition has been established, and the clinical features of this disease remain to be clarified. METHODS: A total of 54 patients with superficial carcinoma of the esophagus (defined as carcinoma limited to the epithelium or superficially invading the lamina propria or submucosa) were classified into two groups according to the longitudinal extent of the lesion. A total of 13 patients with superficially spreading carcinoma (defined as a superficial carcinoma measuring >5 cm and consisting mainly of intraepithelial carcinoma) were compared to 41 patients with nonspreading esophageal carcinoma. RESULTS: One patient with superficially spreading carcinoma had a positive resection margin because of multiple cancerous lesions. The only significant difference in the clinical and pathological features of the two groups was a higher prevalence of associated multiple cancerous lesions in patients with the superficially spreading type. CONCLUSIONS: Superficially spreading carcinoma of the esophagus is often associated with multiple cancerous lesions. For endoscopists and esophageal surgeons, it is important to define the proximal extent of intraepithelial cancer and the presence of multiple cancerous lesions to perform curative resection.

Carcinoma in Situ↗
PubMed2001

Directional distribution of radiation around an accident at a uranium fuel factory in Tokai-mura, 1999.

A beta-ray survey was carried out on concrete walls of the boundary and buildings after a criticality accident at a factory of JCO Co. Ltd. at Tokai-mura. A remarkable distribution of beta counts was observed on the walls depending on the complex internal and external structures of buildings surrounding a precipitation vessel containing uranium 23 days after the accident. The directional distribution function, based on the beta counts on the walls, was consistent with data concerning the neutron dose rate measured in several directions during the accident, suggesting an anisotropic neutron distribution to the residential area.

Humans↗
PubMed2001

Validity and reliability of single-item questions about physical activity.

The Japan Collaborative Cohort Study for Evaluation of Cancer Risk Sponsored by Monbusho (JACC Study) included in its self-administered questionnaires some single-item questions concerning physical activity. We examined the validity of the questions among 1,730 Japanese adults and the reliability of the questions among 1,075 Japanese adults. The validity of the sports and physical exercise questions was estimated by comparing the self-administered questionnaire responses with the time spent on the activity and the energy expenditure index for the previous 12-month period, elicited by the interviewing method used in the Japan Lifestyle Monitoring Study with a minor modification. The Spearman's rank correlation coefficients ranged from 0.43 to 0.60, showing moderate correlations. On the other hand, test-retest reliability was estimated by comparing the responses from two separate surveys conducted roughly one year apart. Weighted kappa coefficients of sports and physical exercise questions, classified according to sex and age, ranged from 0.39 to 0.56, showing moderate reliability; and those of a question about walking ranged from 0.25 to 0.39, showing fair reliability. We suggest that measuring physical activity level with these single-item questions may be appropriate for establishing baseline data that reflects long-term physical activity in a large-scale cohort study targeting lifestyle-related diseases.

Adult↗
PubMed2000

Aggressive preoperative management and extended surgery for hilar cholangiocarcinoma: Nagoya experience.

From 1977 to 1997, surgical resection was possible in 142 (80%) of 177 patients with hilar cholangiocarcinoma after relieving jaundice by single or multiple percutaneous transhepatic biliary drainage followed by percutaneous transhepatic cholangioscopy and/or percutaneous trans-hepatic portal vein embolization. Curative resection was possible in 108 (61%) of the 142 patients, and 100 of these patients underwent various types of hepatectomy with caudate lobectomy for a 30-day operative mortality rate of 6% and 9% hospital mortality. Combined portal vein resection was carried out in 43 cases including 41 hepatectomies and 2 bile duct resections. Hepatopancreatoduodenectomy was performed in 16 patients. Cancer recurrence was observed in 58 of the 108 patients undergoing curative resection. The 3-, 5-, and 10-year survival rates for 100 patients undergoing curative hepatectomy and 8 with curative bile duct resection were 43%, 26%, and 19%; and 31%, 16%, and 0%, respectively; those for 40 patients with positive lymph node metastasis, 84 with perineural invasion, and 43 with combined portal vein resection were 27%, 14%, and 7%; 34%, 21%, and 13%; and 18%, 6%, and 0%, respectively. These survival rates are significantly better than those for 35 patients with unresectable cancer. Curative resection after aggressive preoperative management is recommended as a reasonable surgical approach to hilar cholangiocarcinoma.

Adult↗
PubMed2000

Regional and para-aortic lymphadenectomy in radical surgery for advanced gallbladder carcinoma.

BACKGROUND: There have been no reports on the routine use of regional and para-aortic lymphadenectomy for gallbladder cancer. The aim of this study was to elucidate nodal status, its prognostic influence and the efficacy of lymphadenectomy. METHODS: A retrospective analysis was made of 60 patients who underwent radical resection and routine regional and para-aortic lymphadenectomy. RESULTS: Of the 60 patients, 73 per cent had node-positive disease and 38 per cent had positive para-aortic nodes. Postoperative survival was extremely poor in patients with minimal distant metastasis, and similarly in patients with para-aortic disease. The survival of patients with metastasis limited to the regional nodes was significantly better than that of those with distant metastasis (P = 0.029) or para-aortic disease (P = 0.017) and was not significantly different from that of patients with no metastasis (P = 0.82). CONCLUSION: Regional and para-aortic lymphadenectomy provides no survival benefit for patients with para-aortic disease, which has an influence on poor prognosis equivalent to that of distant metastasis. It has the potential to bring survival benefit only in selected patients with metastasis limited to the regional nodes. A sampling biopsy of the para-aortic nodes before starting radical surgery is recommended because they are involved more frequently than expected.

Aorta↗
PubMed2000

Right trisegment portal vein embolization for biliary tract carcinoma: technique and clinical utility.

BACKGROUND: Right portal vein embolization has become popular in preparation for right hepatic lobectomy. However, right trisegment portal vein embolization (R3PE) is not well established. METHODS: We performed R3PE in 15 patients with biliary tract carcinoma and 1 patient with primary sclerosing cholangitis. We used 2 types of 5.5 F triple-lumen balloon catheters to embolize portal branches of the right trisegment (the left medial, the right anterior, and the right posterior segments). RESULTS: R3PE was successful in all patients without any complications. The calculated volume of the right lobe significantly (P < .01) decreased from 650 +/- 161 cm3 before embolization to 585 +/- 143 cm3 after embolization; the volume of the left lateral segment significantly (P < .0005) increased from 240 +/- 58 cm3 to 361 +/- 66 cm3. The volume of the left medial segment was unchanged. The volume gain of the left lateral segment was larger in patients with R3PE than in those patients (n = 41) with right portal vein embolization (122 +/- 39 cm3 vs 66 +/- 35 cm3; P < .0001). Two of the 16 patients underwent only laparotomy because of peritoneal dissemination, and the remaining 14 patients underwent right hepatic trisegmentectomy with caudate lobectomy. In addition, portal vein resection was also performed in 5 patients, and pancreatoduodenectomy and right hemicolectomy was performed in 3 patients. One patient died of posthepatectomy liver failure 87 days after surgery, a mortality rate of 7.1% (1/14 patients). CONCLUSIONS: R3PE is more useful than standard right portal vein embolization in preparation for right hepatic trisegmentectomy and has the potential to increase the safety of this high-risk surgery for patients with biliary tract carcinoma.

Adult↗
PubMed2000

Management of hilar cholangiocarcinoma: comparison of an American and a Japanese experience.

OBJECTIVE: To compare the experience and outcome in the management of hilar cholangiocarcinoma at one American and one Japanese medical center. SUMMARY BACKGROUND DATA: Controversies surround the issues of extent of resection for hilar cholangiocarcinoma and whether the histopathology of such cancers are similar between patients treated in America and in Japan. METHODS: Records were reviewed of 100 patients treated between 1980 and 1995 at the Lahey Clinic in the United States, and of 155 patients treated between 1977 and 1995 at Nagoya University Hospital in Japan. Selected pathologic slides of resected cancers were exchanged between the two institutions and reviewed for diagnostic concordance. RESULTS: In the Lahey cohort, there were 25 resections, 53 cases of surgical exploration with biliary bypass or intubation, and 22 cases of percutaneous transhepatic biliary drainage or endoscopic biliary drainage without surgery. In the Nagoya cohort, the respective figures were 122, 10, and 23. The overall 5-year survival rate of all patients treated (surgical and nonsurgical) during the study periods was 7% in the Lahey cohort and 16% in the Nagoya cohort. The overall 10-year survival rates were 0% and 12%, respectively. In patients who underwent resection with negative margins, the 5- and 10-year survival rates were 43% and 0% for the Lahey cohort and 25% and 18% for the Nagoya cohort. The surgical death rate for patients undergoing resection was 4% for Lahey patients and 8% for Nagoya patients. Of the patients who underwent resection, en bloc caudate lobectomy was performed in 8% of the Lahey patients and 89% of the Nagoya patients. Histopathologic examination of resected cancers showed that the Nagoya patients had a higher stage of disease than the Lahey patients. CONCLUSIONS: In both Lahey and Nagoya patients, survival was most favorable when resection of hilar cholangiocarcinoma was accomplished with margin-negative resections. Combined bile duct and liver resection with caudate lobectomy contributed to a higher margin-negative resection rate in the Nagoya cohort.

Adult↗
PubMed2000

Thyroid abnormality trend over time in northeastern regions of Kazakstan, adjacent to the Semipalatinsk nuclear test site: a case review of pathological findings for 7271 patients.

From 1949 through 1989 nuclear weapons testing carried out by the former Soviet Union at the Semipalatinsk Nuclear Test Site (SNTS) resulted in local fallout affecting the residents of Semipalatinsk, Ust-Kamenogorsk and Pavlodar regions of Kazakstan. To investigate the possible relationship between radiation exposure and thyroid gland abnormalities, we conducted a case review of pathological findings of 7271 urban and rural patients who underwent surgery from 1966-96. Of the 7271 patients, 761 (10.5%) were men, and 6510 (89.5%) were women. The age of the patients varied from 15 to 90 years. Overall, a diagnosis of adenomatous goiter (most frequently multinodular) was found in 1683 patients (63.4%) of Semipalatinsk region, in 2032 patients (68.6%) of Ust-Kamenogorsk region and in 1142 patients (69.0%) of Pavlodar region. In the period 1982-96, as compared before, there was a noticeable increase in the number of cases of Hashimoto's thyroiditis and thyroid cancer. Among histological forms of thyroid cancer, papillary (48.1%) and follicular (33.1%) predominated in the Semipalatinsk region. In later periods (1987-96), an increased frequency of abnormal cases occurred among patients less than 40 years of age, with the highest proportion among patients below 20 in Semipalatinsk and Ust-Kamenogorsk regions of Kazakstan. Given the positive findings of a significant cancer-period interaction, and a significant trend for the proportion of cancer to increase over time, we recommend more detailed and etiologic studies of thyroid disease among populations exposed to radiation fallout from the SNTS in comparison to non-exposed population.

Adenocarcinoma, Follicular↗
PubMed2000

Clinical evaluation of idiopathic interstitial pneumonia and interstitial pneumonia associated with collagen vascular disease using logistic regression analysis.

OBJECTIVE: To clarify the differences in the clinical features between idiopathic interstitial pneumonia (IIP) and interstitial pneumonia associated with collagen vascular diseases (CVD-IP). METHODS: Symptoms, radiographic findings, pulmonary function, blood chemistry data including autoantibody, and bronchoalveolar lavage fluid (BALF) findings were compared using multiple logistic regression analysis. PATIENTS: The subjects were 44 patients clinically diagnosed with IIP and 33 patients with CVD-IP. RESULTS: The clinical features related to IIP were as follows: male sex, advanced age, past history of hypertension, presence of cough, exertional dyspnea, digital clubbing, an increased level of gamma-globulin, decreased lung volume on chest X-ray, and typical type according to the criteria for IIP on chest X-ray. Increased levels of rheumatoid factor and total cell number in BALF were related to CVD-IP. CONCLUSION: These findings are considered to be useful to differentiate IIP and CVD-IP.

Adult↗
PubMed2000

[Extended liver resection for hilar cholangiocarcinoma].

Liver resection for hilar cholangiocarcinoma should be designed for individual patients, based on both precise diagnosis of cancer extent and accurate evaluation of hepatic functional reserve. Therefore we have developed various types of hepatic segmentectomy. Combined caudate lobectomy is essential in every patient with separated hepatic confluence. So-called extensive hepatectomy, resection of 50% or more of the hepatic mass, includes right lobectomy and right or left trisegmentectomy. Right lobectomy with caudate lobectomy is indicated when the progression of cancer is predominant in the right anterior and posterior segmental bile ducts. The plane of liver transection is along the Cantlie line, and the left hepatic duct is divided just at the right side of the umbilical portion of the left portal vein. Right trisegmentectomy with caudate lobectomy is performed in carcinoma which involves the right hepatic ducts in continuity with the left medial segmental bile duct. The umbilical portion of the left portal vein is freed from the umbilical plate by dividing the small portal branches arising from the cranial side of the umbilical portion. Then the left lateral segmental bile ducts are exposed and divided at the left side of the umbilical portion of the left portal vein. Left trisegmentectomy with caudate lobectomy is suitable for carcinoma which involves the left intrahepatic bile duct in continuity with the right anterior segmental bile duct. Liver transection is advanced along the right portal fissure. The right posterior segmental bile duct is usually divided distal to the confluence of the inferior and superior branches.

Bile Duct Neoplasms↗
PubMed2000

Fatal pancreatitis associated with systemic amyloidosis in a rheumatoid arthritis patient.

We report here a case of severe acute pancreatitis associated with systemic AA amyloidosis in a 69-year-old rheumatoid arthritis (RA) patient. AA amyloid deposition was detected on the walls of small pancreatic arteries and arterioles. The acute pancreatitis was resistant to various interventions, and acute necrotizing pancreatitis and multiple organ failure developed. Although AA amyloidosis in RA patients is rarely complicated with acute pancreatitis, acute pancreatitis in such cases could be severe and intractable and might result in a fatal outcome.

Aged↗
PubMed1999

Isothiazolone derivatives selectively inhibit telomerase from human and rat cancer cells in vitro.

The telomere hypothesis postulates stabilization of telomere length and telomerase activation as key events in cellular immortalization and carcinogeneses. Accordingly, telomerase has been suggested as a novel and highly selective target for design of antitumor drugs. Screening of a chemical library including 16 000 synthetic compounds yielded six that strongly inhibited telomerase activity in extracts of cultured human cells, including four isothiazolone derivatives and two unrelated compounds. The most potent inhibitor was 2-[3-(trifluoromethyl)phenyl]isothiazolin-3-one (TMPI), a concentration of 1.0 microM inhibited telomerase activity by 50% according to a telomere repeat amplification protocol (TRAP) assay. Analysis using partially purified telomerase from AH7974 rat hepatoma cells demonstrated noncompetitive inhibition with the telomere-repeat primer and mixed inhibition with the dNTPs; the inhibition constant was 2.5 microM. TMPI did not inhibit eukaryotic DNA polymerase alpha, beta, or human immunodeficiency virus reverse transcriptase (HIV RT). Thus, inhibition by TMPI was highly selective for telomerase. Inhibition by TMPI was quenched by 1 mM of dithiothreitol or glutathione, suggesting that TMPI inhibits telomerase by acting at a cysteine residue. TMPI inhibition of this enzyme may find application as an antineoplastic agent.

Animals↗
PubMed1999

Comparison of three PET dopamine D2-like receptor ligands, [11C]raclopride, [11C]nemonapride and [11C]N-methylspiperone, in rats.

We studied the tracer kinetics of three dopamine D2-like receptor ligands, [11C]raclopride ([11C]RAC), [11C]nemonapride ([11C]NEM) and [11C]N-methylspiperone ([11C]MSP), in anesthetized rats by tissue dissection, ex vivo ARG and PET in order to clarify their characteristics for PET imaging. The in vivo affinity of the three ligands for the striatum ([11C]MSP > [11C]NEM > [11C]RAC) obeyed the in vitro affinity for dopamine D2 receptors. The affinity of [11C]RAC and [11C]MSP for the cerebellum was very low, but the affinity of [11C]NEM for the cerebellum was compatible to that for the cortex and was not to be ignored. Also the affinity of [11C]MSP for the cortex was relatively high. [11C]RAC showed the highest selectivity. The striatal PET image with [11C]RAC was clearer than that with [11C]NEM or [11C]MSP, but the activity decreased much faster than that measured by tissue dissection because of the partial volume effect. The striatal activity with [11C]NEM remained high and that with [11C]MSP gradually increased. [11C]RAC and [11C]MSP, but not [11C]NEM, showed a high accumulation in the periorbital region.

Animals↗
PubMed1999

Treatment strategy for mucin-producing intrahepatic cholangiocarcinoma: value of percutaneous transhepatic biliary drainage and cholangioscopy.

Intrahepatic cholangiocarcinomas that secrete macroscopically excessive mucin into the biliary system are rare, and few of the previously reported cases have achieved a curative resection. We defined these tumors as "mucin-producing intrahepatic cholangiocarcinomas" and clarify the optimal preoperative and surgical management for them. Eleven patients with mucin-producing intrahepatic cholangiocarcinomas underwent surgical resection in our department. The clinical, radiologic, surgical, and pathologic findings were studied. The clinical presentation of the 11 patients included repeated abdominal pain, jaundice, and fever. Conventional cholangiographies, such as percutaneous transhepatic cholangiography or endoscopic retrograde cholangiography, could not offer precise information about tumor location and extension because of abundant mucin in the biliary system. Using percutaneous transhepatic biliary drainage (PTBD) and percutaneous transhepatic cholangioscopy (PTCS), we were able to drain the mucin and determine precisely the cancer extension into intrahepatic segmental bile ducts. Based on these findings, various types of liver resection with or without extrahepatic bile duct resection were planned, and 10 patients obtained curative resection. The cumulative 5-year survival rate after curative resection was 78%. In patients with mucin-producing intrahepatic cholangiocarcinoma, PTBD and PTCS are important for evaluating the cancer extension. Rational surgery based on accurate preoperative diagnosis improved the prognosis of patients with this disease.

Adult↗
PubMed1999

Macroscopic classification and preoperative diagnosis of intrahepatic cholangiocarcinoma in Japan.

We reviewed the records of 64 patients with resected intrahepatic cholangiocarcinoma (ICC) according to the macroscopic classification proposed by the Liver Cancer Study Group of Japan, in which ICC is classified into three types based on the macroscopic appearance of the cut sur-face of the tumor: mass-forming, periductal-infiltrating, and intraductal growth types. There were 24 patients with the periductal-infiltrating type, 28 with the mass-forming type, and 12 with the intraductal growth type. The mass-forming type essentially showed expansive growth irrespective of hilar invasion. The periductal-infiltrating type of tumor exhibited diffuse infiltration along the portal pedicle, and preoperative planning of the resection procedure was similar to that for primary bile duct carcinoma of the hepatic confluence. Vascular resection and reconstruction was required in some patients with advanced disease. In the intraductal growth type of tumor, precise determination of tumor extent was difficult because of the ambiguity caused by abundant mucin secreted by the tumor and/or by the superficial mucosal spread of the tumor along the bile duct. Percutaneous transhepatic cholangioscopy provided the most reliable information for designing the operative procedure. The macroscopic classification is useful for preoperative diagnosis of tumor extent and for planning the surgical procedure.

Bile Duct Neoplasms↗