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Tetsuichiro Muto

Publications and source records attributed to Tetsuichiro Muto.

51 records · Page 3Linked to original sources
PubMed2002

Predictors of successful hepatic resection: prognostic usefulness of hepatic asialoglycoprotein receptor analysis.

To test the clinical usefulness of hepatic asialogycoprotein receptor analysis in liver surgery, we have conducted univariate and multivariate analysis for the detection of cirrhotic patients and prediction of morbidity after hepatic resection. Liver scintigraphy using technetium 99m-labeled asialoglycoprotein analog (TcGSA), ICG test, and CT hepatic volumetry were undertaken in 158 surgical patients including 111 who underwent hepatic resection. Hepatic functional parameters including Child-Pugh score, indocyanine green retention at 15 minutes (ICG-R15), clearance index (HH15), receptor index (LHL15), receptor concentration ([R]0), total hepatic receptor amount (R0) and hepatic parenchymal volume (HPV) were compared among patients with normal, cirrhotic, and non-cirrhotic damaged liver. Preoperative hepatic functional parameters, resected parenchymal fraction (RPf), operative blood loss, and total receptor amount of the remnant liver (R0-remnant) were compared between patients with and without signs of postoperative liver failure. All parameters but HPV were significantly different among patients with normal, cirrhotic, and noncirrhotic damaged liver. The multivariate analysis selected two significant (p <0.05) parameters, [R]0 and Child-Pugh score for the detection of liver cirrhosis. Of the 111 patients who underwent resection, 14 developed transient signs of postoperative liver failure. Of the parameters tested, presence of liver cirrhosis, LHL15, R0, intraoperative blood loss, and R0-remnant were significantly different between patients with and without signs of postoperative liver failure (p <0.05). The multivariate logistic regression analysis selected only R0-remnant as a significant (p = 0.022) parameter for the prediction of liver failure. The morbidity rate in patients with R0-remnant under 0.05 mmoles was 100%, and the rate decreased in inverse proportion to R0-remnant. In conclusion, combining the ASGP-R concentration ([R]0) and the Child-Pugh score best detected liver cirrhosis in surgical candidates. Cirrhotic patients and patients with a low R0-remnant are at higher risk for postoperative liver failure. The present study confirms the usefulness of hepatic asialogycoprotein receptor analysis in liver surgery.

Adult↗
PubMed2002

Genetic and histological assessment of surgical margins in resected liver metastases from colorectal carcinoma: minimum surgical margins for successful resection.

HYPOTHESIS: There have been few reports on the minimum surgical margins (SMs) required for successful liver resection in patients with colorectal metastases. This minimum requirement may be narrower than the previously recommended margin of 10 mm. OBJECTIVES: To identify the minimum margins by assessing the presence of micrometastases around the tumor using genetic and histological techniques, and to investigate whether SMs are associated with patterns of tumor recurrence or patient survival. DESIGN: Prospective and retrospective studies. SETTING: Tertiary referral cancer center. PATIENTS AND METHODS: Fifty-eight patients who underwent 62 liver resections for hepatic metastasis from colorectal cancer between December 1, 1996, and November 30, 2000, were included in the study. Tissue samples taken from the tumor, surrounding liver parenchyma, and Glisson pedicle near the tumor were tested for K-ras and p53 mutations using the mutant allele-specific amplification method. For the retrospective study on patient outcomes, 194 patients who had undergone liver resections between 1980 and 2000 were analyzed according to their SMs. RESULTS: Of the 62 sets of samples from liver metastases, 39 were positive for K-ras and p53 gene mutations or both. Micrometastases in the liver parenchyma surrounding colorectal metastases were present in 2.0% (4/199) of tested samples and were located within 4 mm of the tumor border. Micrometastases via Glisson pedicle were more common (14.3% [3/21]), but these were also confined to a short distance from the tumor edge (</=5 mm). Of the 5 micrometastases detected by genetic analysis, only 2 were confirmed by histopathological examination. The analysis of patient outcomes demonstrated that the incidence of cut-end recurrence (relapse in the bed of resection) decreased from 20.0% to a range of 5.6% to 7.5% when the SM is 2 mm or more. The incidence of definite cut-end recurrence in patients with SMs less than 2 m, 2 to 4 mm, and 5 mm or wider was 13.3% (6/45), 2.8% (1/36), and 0% (0/102), respectively. The SM was not a significant prognostic factor in patient survival. CONCLUSIONS: Micrometastases around liver tumors are not common, and most are confined to the immediate vicinity of the tumor border. We propose an SM of 2 mm as a clinically acceptable minimum requirement, which carries approximately a 6% risk of margin-related recurrence. Because liver resection provides the only chance of cure, complete removal of the tumor with a minimum margin is justified when technically unavoidable because of the size, location, number of tumors, or successive resections.

Adult↗
PubMed2002

Changing site distribution of colorectal cancer in Japan.

PURPOSE: In North America and other high-risk areas, there has been a proximal shift in the subsite distribution of colorectal cancer. We wanted to determine whether any similar change has occurred in Japan, and where the incidence of this disease has increased sharply. METHODS: Data from the Reports of the Japanese Society for Cancer of the Colon and Rectum were used to analyze the time trend of colorectal cancer in Japan between 1974 and 1994 according to the patients' age at diagnosis and sex, and the site of the tumor within the colon or rectum. RESULTS: The percentage of patients over the age of 70, especially females, increased. The increase in the percentage of right-sided colon cancer in colorectal cancer cases was accompanied by a continuous decline in the percentage of rectal cancer in both sexes at all ages. In general, the percentage of right-sided colon cancer in colon cancer cases was stable in men, but increased in women. The rate among patients older than 70 years increased in men, but predominated and remained stable in women. No proximal shift in colon cancer was found in either sex under the age of 69. CONCLUSION: These findings indicated that a proximal shift in the subsite distribution of colorectal cancer has occurred in Japan. This rightward shift of colorectal cancer is due to the decreasing proportion of rectal cancer. Furthermore, the increasing proportion of older patients, especially females, may be another major determinant of the changing colon cancer subsite distribution.

Aged↗
PubMed2002

Extended lymphadenectomy and preoperative radiotherapy for lower rectal cancers.

BACKGROUND: Extended lymphadenectomy including lateral node dissection (EXT-L) contributes to a low incidence of local recurrence of lower rectal cancer. However, EXT-L is frequently associated with impairment of sexual and urinary function. We therefore compared the effectiveness of preoperative radiotherapy with that of EXT-L. METHODS: One hundred fifteen patients were studied. Seventy-eight patients underwent preoperative radiotherapy with a total dose of 50 Gy (Rad[+] group), and 37 did not (Rad[-] group). Seventy-five patients received EXT-L (EXT-L[+] group), and 40 did not (EXT-L[-] group). Patients were further divided into 4 subgroups (Rad[+]&EXT-L[-], Rad(+)&EXT-L[+], Rad[-]&EXT-L(+), and Rad[-]&EXT-L[-]), and clinicopathologic features were examined. In the Rad(+) group, the relation between the p53 gene and survival was also examined. RESULTS: There was a significant difference in disease-free survival between the Rad(+) and Rad(-) groups (5-year disease-free survival rate, 74.6% vs 45.9%; P =.006). However, there was no significant difference between the Rad(+)&EXT-L[-] and Rad[-]&EXT-L(+) groups. The p53 gene status did not affect survival in the Rad(+) group. CONCLUSIONS: This study suggests that in terms of curative effect, preoperative radiotherapy can be one alternative therapy in place of EXT-L for patients with lower rectal cancer.

Adenocarcinoma↗
PubMed2002

Familial adenomatous polyposis associated with multiple endocrine neoplasia type 1-related tumors and thyroid carcinoma: a case report with clinicopathologic and molecular analyses.

We describe a sporadic case with familial adenomatous polyposis, multiple endocrine neoplasia type 1 (MEN1)-related tumors (an endocrine cell tumor of the pancreas and bilateral parathyroid tumors), and a papillary thyroid carcinoma. To clarify how mutations of the adenomatous polyposis coli ( APC ) gene and the MEN1 gene, responsible for familial adenomatous polyposis and MEN1, respectively, might have contributed to tumorigenesis in this case, we studied germline mutations in both genes and loss of heterozygosity at their genetic loci in multiple lesions. In addition, we performed immunohistochemistry for beta-catenin, associated with the function of the APC gene. A germline mutation was found in the APC gene but not in the MEN1 gene. Normal allelic loss at the APC gene locus was observed in bilateral parathyroid tumors. Immunohistochemical staining of beta-catenin demonstrated accumulation in the cytoplasm in addition to membrane staining in all analyzed tumors and a strong nuclear reaction in the endocrine cell tumor of the pancreas. The presence of normal allelic deletions of the APC gene in bilateral parathyroid tumors and nuclear staining of beta-catenin in the pancreatic tumor in addition to the germline mutations suggests that functional loss of the APC gene played an important role not only in familial adenomatous polyposis but also in the MEN1-related tumors in this case.

Adenomatous Polyposis Coli↗
PubMed2002

[Pancreatic islet cell carcinoma with multiple hepatic metastases successfully treated with a streptozocin/5-FU regimen--a case report].

A 53-year-old woman was hospitalized because of lientery and steatorrhea. CT scans revealed a pancreatic head tumor along with multiple liver tumors. The pancreatic head tumor had spread to the duodenum. Following tumor biopsy with gastrointestinal fiberscopy, we diagnosed a pancreatic malignant islet cell tumor with multiple liver metastases. Since there was no clinical evidence of recognized endocrinopathy, we diagnosed "nonfunctioning" tumor. At first we administered only 5-FU at a dose of 370 mg/m2/day continuously for two weeks. However, neither the pancreatic head tumor nor the metastatic liver tumors changed in size. We then administered streptozocin and 5-FU at doses of 1,000 mg/m2 and 370 mg/m2, respectively, every week. The patient received a total of 10 g/m2 of streptozocin. After this treatment, the enlarged metastatic liver tumors were reduced in size, with marked improvement in liver enzyme. Toxic reactions to this regimen were mild. Only grade 1 nausea and alopecia were observed during the treatment. No hematological toxicity was observed, nor, with sufficient diuresis, was nephrotoxicity, demonstrating that this regimen can be administered safely.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Budding as a useful determinant of the optimal treatment for T1 rectal carcinomas.

BACKGROUND/AIMS: If a locally excised specimen has poorly differentiated or undifferentiated histology, positive vascular invasion, or massive invasion to the cut end or a positive margin, additional surgery is recommended for the treatment of T1 rectal carcinoma. However, positive predictive values of these histological criteria are low. This study was undertaken to clarify more reliable risk factor(s) for lymph node metastasis in T1 rectal carcinomas. METHODOLOGY: In 58 patients with T1 rectal carcinoma undergoing local excision or radical surgery, the associations between lymph node metastasis or intrapelvic recurrence and clinicopathological features were studied using multiple regression analysis with special reference to tumor budding at the invasive front. RESULTS: Lymph node metastasis was observed in 1 of 9 patients undergoing additional bowel resection after local excision, and in 2 of 24 patients undergoing radical surgery alone. Intrapelvic extrarectal recurrence was observed in 3 of 25 patients undergoing local excision alone. Logistic regression analysis revealed that budding at the invasive front alone was significantly associated with lymph node metastasis or intrapelvic recurrence (p = 0.0484). CONCLUSIONS: Additional bowel resection with lymph node dissection should be recommended for locally excised T1 rectal carcinoma with budding at the invasive front.

Adult↗
PubMedDate not supplied

Colon cancer complicated by vascular and intestinal anomaly.

We present a case of colon cancer in a patient with an anomalous mesenteric artery, a middle mesenteric artery, associated with intestinal nonrotation. At surgery for such a rare case, an exact grasp of the feeding artery, the draining vein, and the lymphatic flow of the tumor is necessary to perform appropriate bowel resection and oncological nodal dissection. Selective angiography and preoperative endoscopic submucosal injection of India ink near the tumor were thought to be essential for surgical decision-making.

Colon↗
PubMedDate not supplied

The repeated hepatectomy for frequent recurrence of hepatic metastasis from gastrointestinal stromal tumor of the stomach.

Although in recent years hepatic resection has become a safe procedure, there are few data on repeat liver resection for hepatic metastases from gastrointestinal stromal tumor. A 60-year-old Japanese man underwent partial gastrectomy and extended right hepatectomy for gastrointestinal stromal tumor of the stomach with liver metastasis. However, liver metastasis recurred at the interval of less than 1 year. Therefore, the patient underwent a total of six liver resections. The liver resections comprised four R0, one R1 and one R2 resection. To our knowledge, six times for liver resection performed on one patient is a maximum. This patient survived 43 months after the first surgery. Despite frequent recurrence of hepatic metastasis from gastrointestinal stromal tumor, repeated hepatectomy provides a survival benefit if complete removal of all tumorous masses appears possible.

Fatal Outcome↗
PubMedDate not supplied

Pathological changes of advanced lower-rectal cancer by preoperative radiotherapy.

BACKGROUND/AIMS: In the treatment of lower rectal cancer, we examined the pathological effects of preoperative radiotherapy on intramural spread of tumor and risk factors for local recurrence, including tumor deposit, budding growth of primary tumors, and micrometastasis to lymph nodes. METHODOLOGY: Ninety-four patients who underwent surgery for lower rectal cancer were selected. Forty-seven patients received preoperative radiotherapy, at a total dose of 50 Gy [Rad(+) group], whereas 47 did not [Rad(-) group]. Intramural spread was evaluated between the Rad(+) and Rad(-) groups. For analysis of tumor deposit, budding, and micrometastasis, 25 stage-matched patients were selected in both groups. RESULTS: Intramural spread was significantly less in the Rad(+) group, compared with the Rad(-) group. The Rad(+) group showed a significant decrease in tumor deposit, budding, and micrometastasis, compared with the Rad(-) group. In patients having overt lymph node metastases or not, the tumor deposit and budding were significantly higher in patients having overt metastases, compared with those not having them, in the Rad(-) group, whereas there was no significant difference in the Rad(+) group. CONCLUSIONS: Intramural spread and tumor deposit, budding, and micrometastasis were significantly decreased in the Rad(+) group, compared with the Rad(-) group. These results suggested effects of preoperative radiotherapy for sphincter preservation, as well as for decreasing the local recurrence rate.

Adult↗
PubMedDate not supplied

Evaluating the combination of molecular prognostic factors in tumor radiosensitivity in rectal cancer.

BACKGROUND/AIMS: The local recurrence ratio following surgery alone is higher in patients with rectal cancer than in those with colon cancer. Preoperative radiotherapy reduces the rate of local recurrence and improves the chances of survival in patients with resectable advanced rectal carcinoma. Identification of predictive indicators of radiosensitivity is useful in selecting patients best suited for preoperative radiotherapy and thus helps to avoid unnecessary preoperative treatment. We investigated whether the combination of Ku, p53, p21, and p16 predicted tumor radiosensitivity. METHODOLOGY: We studied 96 cases with advanced rectal carcinoma. In preradiation biopsy specimens of tumor samples, all immunoreactive nuclei of cells stained positive for Ku, p53, p21, and p16 were evaluated by immunohistochemistry. The expression of p53, p21 and p16 in more than 5% of tumor cells were defined as positive, whereas both Ku70 and Ku86 protein in more than 70% of such cells were defined as Ku positive. The expression patterns of Ku, p53, p21, and p16 were examined for association with tumor radiosensitivity, which was determined according to the criteria of histopathologic assessment of radiotherapy effects. RESULTS: Univariate analysis showed a correlation between the expression patterns of Ku, p53, p21, and p16 and tumor radiosensitivity, while multivariate analysis showed that the expression pattern of Ku and p16 significantly correlated with tumor radiosensitivity. The combination of Ku and p16, or Ku, p53, p21 and p16 was therefore a good predictive marker for tumor radiosensitivity. CONCLUSIONS: These findings tend to support the hypothesis that the combination of Ku, p53, p21, and p16 expression after radiotherapy can act as a marker for radiosensitivity. Further investigation is needed, as the number of cases in this study was limited.

Adult↗
PubMedDate not supplied

Endoscopic total layer resection with laparoscopic sentinel node dissection and defect closure for duodenal carcinoid.

Tiny duodenal carcinoid is easily treated by endoscopic mucosal resection method. On the other hand, this tumor develops in the deeper layer of the mucosa, therefore it invades like a submucosal tumor. The resection of the total layer is sometimes needed to get a tumor-free margin. Moreover, lymph node metastasis is not predicted only by tumor size. Laparoscopic surgery is less invasive compared with conventional open surgery. We describe a new method, endoscopic total layer resection with laparoscopic sentinel node dissection and defect closure. This type of combined method should be performed in order to help decide whether to convert to conventional lymph node dissection, or not.

Carcinoid Tumor↗
PubMedDate not supplied

Expression pattern of telomerase reverse transcriptase in rectal carcinoma predicts tumor radiosensitivity, local recurrence and disease-free survival.

BACKGROUND/AIMS: Predictive indicators of radiosensitivity in rectal cancer are required in order to avoid unnecessary preoperative radiotherapy. Telomeres are specialized structures at the ends of chromosomes that protect against that such as irradiation. Lower telomerase activity has been reported to be related to radiosensitivity in vitro or vivo. The aim of this study was to examine the possible role of telomerase reverse transcriptase expression, which is correlated to telomerase activity, in determining tumor radiosensitivity, local recurrence, and disease-free survival in patients with rectal carcinomas. METHODOLOGY: We studied 96 cases with advanced rectal carcinoma. In preradiation biopsy specimens of tumor samples, the number of cells stained positive for telomerase reverse transcriptase protein was evaluated by immunohistochemistry. RESULTS: The expression pattern of telomerase reverse transcriptase protein correlated with tumor radiosensitivity (P=0.0007). All tumors that had a high percentage of telomerase reverse transcriptase positive cells were radioresistant. High telomerase reverse transcriptase expression pattern is a predictive marker for high local recurrence or poor survival in patients with rectal cancer (P=0.011, P=0.0005). Telomerase reverse transcriptase expression and histopathological grade were significant prognostic variables for disease-free survival in the multivariate analysis (P=0.0003, P=0.0091). CONCLUSIONS: Telomerase reverse transcriptase raises the predictive possibility of tumor radiosensitivity in rectal cancer. Telomerase reverse transcriptase might be a useful parameter for patient selection for preoperative radiotherapy in rectal carcinoma.

Adenocarcinoma↗
PubMedDate not supplied

Repeated resection for intra-abdominal and retroperitoneal liposarcomas: long-term experience in a single cancer center in Japan.

Intra-abdominal or retroperitoneal liposarcomas are huge, and local recurrence is a common event. There is still no consensus concerning debulking or repeated resection. Twelve patients who had surgery for intra-abdominal or retroperitoneal liposarcomas at the Cancer Institute Hospital (Tokyo, Japan) during 1981-2002 were enrolled. Eight patients underwent complete resection, for a resectability rate of 67%. Combined resection of adjacent organs was necessary to obtain clear margins in 10 of the 12 patients (83%). A patient who underwent R2 resection survived 13.2 years in a dormant state without tumor regrowth. Resection of second (five patients), third (three patients), or seventh (one patient) for local recurrence or regrowth tumors was successfully performed. A patient survived 21.5 years after four R0 resections and three R2 resections. Our experience suggests that both near-total and repeated resection might improve survival benefit.

Abdominal Neoplasms↗