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Tetsuichiro Muto

Publications and source records attributed to Tetsuichiro Muto.

At least 37 records · Page 2Linked to original sources
PubMed2004

A new scoring system to classify patients with colorectal liver metastases: proposal of criteria to select candidates for hepatic resection.

BACKGROUND: Although many studies have reported the beneficial effects of hepatic resection for colorectal liver metastases on survival rates, it is still difficult to preoperatively select good candidates for hepatectomy. METHODS: Fifteen clinicopathological features, which were recognized only before or during surgery, were selected retrospectively in 81 consecutive patients in one hospital (Group I). These features were entered into a multivariate analysis to determine independent and significant variables affecting long-term prognosis after hepatectomy. Using selected variables, we created a scoring formula to classify patients with colorectal liver metastases to select good candidates for hepatic resection. The usefulness of the new scoring system was examined in a series of 70 patients from another hospital (Group II). RESULTS: Multivariate analysis, i.e., Cox regression analysis, showed that serosa invasion of primary cancers (P = 0.0720, risk ratio = 2.238); local lymph node metastases of primary cancers, i.e., Dukes' C (P = 0.0976, risk ratio = 2.311); multiple nodules of hepatic metastases (P = 0.0461, risk ratio = 2.365); nodules of hepatic metastases greater than 5 cm in diameter (P =0.0030, risk ratio = 4.277); and resectable extrahepatic distant metastases (P = 0.0080, risk ratio = 4.038) were significant and independent prognostic factors for poor survival after hepatectomy. Using these five variables, we created a new scoring formula to classify patients with colorectal liver metastases. Finally, our new scoring system classified patients in Group II and Group I well, according to long-term outcomes after hepatic resection. CONCLUSIONS: Our new scoring system to classify patients with colorectal liver metastases is simple and useful in the preoperative selection of good candidates for hepatic resection. Although many studies have reported the beneficial effects of hepatic resection for colorectal liver metastases on survival rates, it is still difficult to preoperatively select good candidates for hepatectomy.

Colorectal Neoplasms↗
PubMed2004

Correlations between lymph node metastasis and depth of submucosal invasion in submucosal invasive colorectal carcinoma: a Japanese collaborative study.

BACKGROUND: Depth of submucosal invasion (SM depth) in submucosal invasive colorectal carcinoma (SICC) is considered an important predictive factor for lymph node metastasis. However, no nationwide reports have clarified the relationship between SM depth and rate of lymph node metastasis. Our aim was to investigate the correlations between lymph node metastasis and SM depth in SICC. METHODS: SM depth was measured for 865 SICCs that were surgically resected at six institutions throughout Japan. For pedunculated SICC, the level 2 line according to Haggitt's classification was used as baseline and the SM depth was measured from this baseline to the deepest portion in the submucosa. When the deepest portion of invasion was limited to above the baseline, the case was defined as a head invasion. For nonpedunculated SICC, when the muscularis mucosae could be identified, the muscularis mucosae was used as baseline and the vertical distance from this line to the deepest portion of invasion represented SM depth. When the muscularis mucosae could not be identified due to carcinomatous invasion, the superficial aspect of the SICC was used as baseline, and the vertical distance from this line to the deepest portion was determined. RESULTS: For pedunculated SICC, rate of lymph node metastasis was 0% in head invasion cases and stalk invasion cases with SM depth <3000 micro m if lymphatic invasion was negative. For nonpedunculated SICC, rate of lymph node metastasis was also 0% if SM depth was <1000 micro m. CONCLUSIONS: These results clarified rates of lymph node metastasis in SICC according to SM depth, and may contribute to defining therapeutic strategies for SICC.

Adult↗
PubMed2004

Extended left hepatectomy by severing all major hepatic veins with reconstruction of the right hepatic vein.

Curative liver resection is technically challenging when multiple liver metastases from colon cancer involve the confluence of the three major hepatic veins. We report two cases of successful extended left hemihepatectomy achieved by severing all of the major hepatic veins together with the wall of the inferior vena cava, to resect liver metastases from colon cancer. Reconstruction of the right hepatic vein was done after unroofing the right anterior area of the liver with a direct anastomosis of the right hepatic vein. We did not need to perform total vascular exclusion or portovenous shunting during the liver transection. This simple and safe method can increase the surgical indications for previously unresectable tumors.

Aged↗
PubMed2004

The endoscopic evaluation of gastritis, gastric remnant residue, and the incidence of secondary cancer after pylorus-preserving and transverse gastrectomies.

BACKGROUND: Pylorus-preserving gastrectomy (PPG) and transverse gastrectomy (TrG) have been accepted as function-preserving procedures for node-negative early gastric cancer. It is believed that a better quality of life is guaranteed after PPG or TrG compared to that after distal subtotal gastrectomy (DSG) with Billroth type-I reconstruction. However, objective evaluations of the gastric remnant following gastrectomy have not been widely reported, and the real advantages and disadvantages of PPG or TrG over DSG remain unclear. Moreover, the risk of secondary cancer after PPG or TrG is uncertain. METHODS: Between 1991 and 2000, 834 DSGs were carried out in our institute for preoperatively diagnosed patients with early gastric cancer. The degree of residual gastritis and the amount of diet residue in the gastric remnant were evaluated by annual gastrointestinal endoscopic investigations prospectively for 72 patients after PPG, 95 patients after TrG, and 60 patients after DSG. These analyses were performed using the RGB classification (residue, gastritis, bile). The incidence of disease greater than or equal to grade 2 was calculated, and the time trends of the incidence for each procedure were also studied for 3 years after gastrectomy. In addition, secondary cancer cases in the gastric remnant mucosa were checked for each procedure during this period, and the incidence of secondary cancer after each operation was calculated. RESULTS: The incidence of gastritis, of grade 2 or more, found in the gastric remnant was significantly lower after PPG (1.4%) and TrG (2.1%) than after DSG (43.3%). However, the incidence of moderate or greater residue in the gastric remnant, grade 2 or more, was significantly higher after PPG (45.8%) and TrG (40.0%) than after DSG (11.7%). The analysis of time trends of gastritis and diet residue reflected the significant advantage or disadvantage for each procedure 1 year after surgery. The analysis also included these factors without consideration of elapsed time following surgery. Two patients after PPG (2.8%) and three patients after TrG (3.2%) developed secondary cancer in the gastric remnant. No DSG-treated patient showed new cancer genesis in the remaining stomach. CONCLUSION: PPG and TrG have the advantage over DSG in preventing postoperative gastritis in the gastric remnant. On the other hand, moderate or greater diet residue in the gastric remnant is more common after PPG or TrG than after DSG. For the risk of carcinogenesis in the remnant gastric mucosa, we could not conclude that there was any apparent difference between these range-limited gastrectomies and conventional DSG. Further study is necessary to determine the significant advantages and disadvantages of using PPG or TrG.

Aged↗
PubMed2004

A clinical overview of familial adenomatous polyposis derived from the database of the Polyposis Registry of Japan.

The clinical situation of familial adenomatous polyposis (FAP) in Japan has changed in the period since the last analysis of data of the Japanese Polyposis Center. To reevaluate our data and elucidate the changes we analyzed the records of the 1390 FAP patients in 900 families registered with the Polyposis Committee of the Japanese Society for Cancer of the Colon and Rectum. In the 13-year period 1990-2003, clinical differences between men and women with FAP diminished. The postoperative prognosis was substantially better in patients without advanced colorectal cancer (stage > or = T2) than in those with early cancer or no cancer. Mean age at death improved from 42.5 years in the period before 1990 to 46.0 years, and it was a result of a decreased proportion of deaths from colorectal cancer. The distribution of colorectal cancer in FAP patients was similar to that in the general population. Desmoid tumors accounted for about 10% of deaths in the recent 13 years (1990-2003). The cumulative risk of rectal cancer in the preserved rectum was 12% at 10 years and 23% at 15 years. The registry system in Japan revealed a new clinical situation in FAP patients, and the findings of this study will be useful to improve the prognosis of patients with FAP.

Adenoma↗
PubMed2003

Hepatic resection for colorectal metastasis with macroscopic tumor thrombus in the portal vein.

Metastatic lesions in the liver derived from colorectal cancer rarely invade the portal vein macroscopically. Little is known about the clinical characteristics and outcome of surgical treatment in patients with tumor thrombus in the portal vein. Medical charts of 142 consecutive patients who underwent hepatic resection for colorectal metastasis were reviewed retrospectively. Of the 142 patients, 4 (2.8%) had macroscopic portal vein invasion. The most prominent characteristic on preoperative imaging was segmental staining in the arterial phase shown by dynamic computed tomography (CT) or by CT arteriography. This finding was positive in all four of the patients. All patients underwent anatomic liver resection and were alive with no evidence of disease for an average of 52.3 months (range 21-102 months). Macroscopic tumor thrombus in the portal vein is rare with colorectal metastasis. It is accurately detected by CT by checking for signs of segmental staining. In this setting, anatomic major resection of the liver is essential for curative treatment.

Adenocarcinoma↗
PubMed2003

Minute gastric carcinoid tumor with regional lymph node metastasis.

We report a patient with a minute gastric carcinoid tumor with lymph node metastasis, and a small gastric cancer. A 50-year-old man having a diagnosis of an elevated lesion on the anterior wall of the gastric body, detected by a series of upper gastrointestinal examinations, was referred to the Cancer Institute Hospital. Careful upper fluoroscopy disclosed a small superficial depressed lesion with converging folds and a superficial elevated lesion covered with nonspecific gastric mucosa. With a final preoperative diagnosis of depressed early cancer and minute carcinoid tumor of the stomach, made by upper gastrointestinal examinations including biopsy, the patient underwent segmental gastrectomy and perigastric lymph node dissection. Histological examination of the resected specimen revealed a lymph node metastasis from a gastric carcinoid tumor of 5-mm diameter, in addition to an early gastric cancer of poorly differentiated adenocarcinoma. Small gastric carcinoid tumors have been regarded as being benign neoplasms biologically. However, the case we present suggests that attention should be paid to the possibility of metastasis at the time of treatment for a minute sporadic gastric carcinoid tumor. We therefore discuss the malignant potential of these tumors, mainly from the viewpoint of histopathological classification, to gain understanding so that the patients can be treated adequately.

Adenocarcinoma↗
PubMed2003

Colliding gastric and intestinal phenotype well-differentiated adenocarcinoma of the stomach developing in an area of MALT-type lymphoma.

A 73-year-old man presented with an abnormal gastric shadow during a check-up of atomic bomb survivors. Radiological examination and endoscopy of the upper gastrointestinal tract revealed a protruding tumor, type 0-I+IIa, on the lesser curvature of the midstomach. An initial diagnosis of early gastric cancer was made and a segmental gastrectomy was planned. However, distal gastrectomy with D3 lymph node dissection was necessary, because intraoperative frozen section showed that the paraaortic lymph nodes (N3) were positive for cancer. The tumor in the resected specimen was, microscopically, a well-differentiated tubular adenocarcinoma (tub1) with pT2 (MP), pN3, ly2, and v1, in final (f) stage IV. The tumor cells of the type 0-I segment appeared as gastric phenotype and those of the type 0-IIa segment as intestinal phenotype. The border between the two was distinct. The tumor had focally invaded the muscularis propria where only the gastric phenotype was shown and the histological type became less differentiated. Thus, special attention should be paid to possible unexpected deep-wall invasion and lymph node metastasis in well-differentiated adenocarcinomas of the gastric phenotype. Further, in this patient, diffusely proliferating low-grade lymphoma was also observed incidentally in the gastric mucosa within and around the carcinoma. This was diagnosed as mucosa-associated lymphoid tissue (MALT)-type lymphoma with aberrant expression of BCL10. Finally, this case was considered to be a colliding gastric and intestinal phenotype well-differentiated adenocarcinoma of the stomach developed in an area involved by MALT-type lymphoma. Because no Helicobacter pylori was detected throughout the mucosae and the patient had no history of its infection, the three tumors may have developed under the same conditions as those seen in Helicobacter pylori infection, but without this infection.

Adenocarcinoma↗
PubMed2003

Multiple primary cancer: an experience at the Cancer Institute Hospital with special reference to colorectal cancer.

BACKGROUND: Cancer patients are at high risk of developing a second cancer after the treatment of initial cancers. Understanding the characteristics of multiple primary cancer is important to establish an effective surveillance program for the early detection of second cancers. METHODS: We analyzed the cancer registry records from 1986 to 1995 at the Cancer Institute Hospital. The combination of the sites of the index and second cancers and the time intervals between the two cancers were examined. For colorectal cancer, another database of patients between 1946 and 1991 was analyzed, with special reference to synchronous and metachronous cancers. RESULTS: Out of 24,498 registered cases, there were 1281 (5.2%) multiple cancers, of which 464 (1.9%) were in the same organs and 817 (3.3%) were in other organs. Gastric or colorectal cancer frequently developed as the second cancer regardless of the site of the index cancer. Although the majority of the second cancers developed within 3 years after the index cancer, some developed 5 years or more after the index cancer. In colorectal cancer, the cases with metachronous cancer were similar to those with hereditary nonpolyposis colon cancer. The frequent combination of an advanced index cancer and an advanced second cancer and relatively poor survival after the second cancers in the metachronous cases may reflect delayed diagnosis of the second colorectal cancer. CONCLUSION: Careful attention should always be paid to the second cancer in treating cancer patients. Further analysis by individual site of the index cancers is needed to construct an effective surveillance for second cancers.

Adult↗
PubMed2003

Surgical resection of liver metastases of gastric cancer: an analysis of a 17-year experience with 22 patients.

BACKGROUND: The justification for surgical resection of liver metastases from gastric cancer remains controversial. METHODS: Twenty-two patients who underwent 26 hepatectomies for liver metastases of gastric cancer between 1985 and 2001 were analyzed. Fifteen clinicopathologic factors were evaluated with univariate and multivariate analyses for survival after hepatic resection. RESULTS: The overall 1-year, 3-year, and 5-year survival rates after hepatectomy for gastric metastases were 73%, 38%, and 38%, respectively. Five patients survived for more than 3 years without recurrence, 3 of whom had synchronous metastases resected at the time of gastrectomy. The best results after surgical resection for liver metastases of gastric cancer were obtained with solitary metastases less than 5 cm in size. The number of liver metastases (solitary or multiple) was the only significant prognostic factor according to both univariate and multivariate analyses. CONCLUSION: Surgical resection for liver metastases of gastric cancer may be beneficial for patients with a solitary metastasis, whether it is synchronous or metachronous.

Aged↗
PubMed2003

Segmental resection of the third portion of the duodenum for a gastrointestinal stromal tumor: a case report.

We describe a case in which segmental resection of the third portion of the duodenum was performed for a gastrointestinal stromal tumor (GIST). A 31-year-old woman was found to have a 3.5 cm hypovascular tumor at the posterior inferior aspect of the pancreatic head. Preoperative duodenal biopsy revealed that the tumor was positive for c-kit and vimentin, and was diagnosed as a duodenal GIST. Segmental resection of the third portion of the duodenum with papilloplasty and duodenojejunostomy was carried out and there were no postoperative complications. Pancreatoduodenectomy is not always necessary in the treatment of a duodenal GIST. This duodenectomy procedure can serve as a less extensive resection for a duodenal GIST located in the third portion of the duodenum.

Adenocarcinoma↗
PubMed2003

Changes in colorectal cancer during a 20-year period: an extended report from the multi-institutional registry of large bowel cancer, Japan.

PURPOSE: This study was designed to examine trends of colorectal cancer in relation to age, gender, site, and survival during the past 20 years. METHODS: The multi-institutional registry of the Japanese Society for Cancer of the Colon and Rectum offered 87,695 surgical cases with invasive adenocarcinoma during 1978 to 1997 for analysis. We calculated survival rates and used the Cox's proportional hazard model for cases during 1978 to 1994. RESULTS: The number of cases showed a 2.5-fold increase with consistent male predominance confined to the distal colon and the rectum. Colon cancer in the last five-year period was more likely right-sided for females (odds ratio, 1.26; 95 percent confidence interval, 1.16-1.38) and males (odds ratio, 1.16; 95 percent confidence interval, 1.06-1.25) compared with the first period. Cancers in younger patients were more likely at Stage III to IV in the late 1990s if the cancers were in the distal colon, the rectum (for both genders), or the proximal colon (for females). Survival was improved except for cases with proximal colon cancer of Stage IV. In the multivariate analysis, hazard ratios for death in the postoperative five years were 0.77, 0.59, and 0.66 for proximal colon, distal colon, and rectal cancers, respectively, in the last period as compared with those in the first period [corrected]. Reduced hazard ratio for females was the largest for proximal colon cancer with Stage I to II. CONCLUSION: Although surgical outcome was largely improved, delayed presentation or diagnosis in younger patients remained a problem. Preferential localization in the proximal colon and survival benefit for females should be investigated.

Adenocarcinoma↗
PubMed2003

Recent advances in diagnosis and treatment of colorectal T1 carcinoma.

PURPOSE: Colorectal T1 tumors (submucosally invasive carcinoma) have special characteristics in terms of pathology, diagnosis, and treatment. The clinicopathologic features of T1 tumors are reviewed. RESULTS: Incidence of T1 tumors was approximately 10 percent, and the percentage of node metastasis was 10 to 11 percent, whereas hepatic metastasis was <1 percent. Macroscopically they were divided into three types: polypoid, ulcerating, and flat. The ulcerating type was divided into two subgroups: polypoid growth and nonpolypoid growth based on the histologic appearance of resected specimens. The tools for detecting T1 tumors were fecal occult blood test and colonoscopy, and magnifying colonoscopy and chromography facilitate more precise diagnosis. Ultrasonography also was useful for the correct diagnosis of the depth of cancer invasion. Most polypoid and some flat T1 tumors were safely treated by polypectomy or endoscopic mucosal resection alone; however, when resected specimens contained risk factors for metastasis, such as deep invasion (sm2, sm3) and vessel invasion, additional surgery was necessary for cure. For rectal T1 tumors, the most appropriate procedure should be carefully selected from several therapeutic options to preserve anal function. CONCLUSION: The management of colorectal T1 tumors should be determined according to the types of macroscopic appearances. The risk of node metastasis could be predicted based on risk factors that were characterized by the level of cancer invasion and the presence or absence of vessel invasion. Minimally invasive treatment should be chosen for colorectal T1 tumors.

Clinical Trials as Topic↗
PubMed2003

Multicenter randomized controlled trial for the treatment of ulcerative colitis with a leukocytapheresis column.

The administration of steroids is not always effective for the treatment of ulcerative colitis (UC). Their long-term use often causes adverse effects which sometimes result in their stoppage and acute exacerbation. Therefore, an alternative treatment is necessary in order to decrease steroid dosage and avoid the clinical problems associated with steroids. Methods The effectiveness and adverse effects of a leukocytapheresis (LCAP) were investigated in a controlled multicenter trial with randomized assignment of 76 active-stage UC patients in two groups. In the LCAP group (39 patients), LCAP weekly for 5 weeks as an intensive therapy was added to the on-going drug therapy, while steroids were maintained but not increased, and then LCAP was gradually reduced to once every 4 weeks as a maintenance therapy. In the high dose prednisolone (h-PSL) group (37 patients), PSL was added or increased 30 approximately 40 mg/day for moderately severe and 60 approximately 80 mg/day for severe patients and then gradually tapered. Findings The LCAP group showed a significantly higher effectiveness (74% vs. 38%; p=0.005) and lower incidence of adverse effects (24% vs. 68%; p<0.001). The patients were able to continue the trial for a longer period in the LCAP group than the h-PSL group (p=0.012). Clinical activity and endoscopic indexes showed the LCAP group had better improvements than the h-PSL group. Interpretation The results of the trial show that LCAP permits a reduction in total PSL dosage and is more effective and safer than high-dose PSL administration for intensive therapy, and LCAP may maintain remission longer than PSL.

Adult↗
PubMed2003

[Current status of sentinel node navigation surgery in colon cancer].

The feasibility of sentinel node (SN) mapping and its diagnostic reliability are now being determined in colorectal cancer, but the reports issued in 2000 or later suggest that they are promising with SN detection rates of 94-100% and overall diagnostic accuracy of regional lymph node status based on SN status of 86-100%. In particular, patients with a pT1 or pT2 colorectal cancer are suggested to be the best candidates for SN mapping, with diagnostic accuracy of almost 100%. On the contrary, the effects on recurrence and survival rates in colorectal cancer have not yet been verified between patients with and without micrometastasis in the SN. In accordance with the Japanese Classification of Colorectal Carcinoma, surgery for D2 (or D3) lymph node dissection have been routine in Japan for T1 or T2 colon cancers without any postoperative sequelae, and can harvest nearly all SNs without lymphatic mapping, because SNs are anatomically distributed in the paracolic and intermediate nodes. Patients with a T1 or T2 colon cancer are the best candidates for sentinel node navigation surgery (SNNS) as well as for laparoscopy-assisted colectomy (LAC). However, intraoperative colonofiberoscopy to inject a pigment tracer into the colic wall for lymphatic mapping is problematic to the LAC procedure thereafter. For this reason, SNNS might not be accepted widely in colon cancer surgery in the near future.

Colonic Neoplasms↗