Biomedical subjects

T Muto

Publications and source records attributed to T Muto.

730 records · Page 41Linked to original sources

PubMedDate not supplied

Duct-ectatic type of mucin producing tumor of the pancreas--new concept of pancreatic neoplasia.

BACKGROUND/AIMS: Although there have been recent reports of mucin-producing tumor of the pancreas, there has been no thorough clinicopathological analysis of a large number of cases. MATERIALS AND METHODS: Two hundred forty four cases of mucin-producing tumor of the pancreas from Japanese, European and American reports, together with 15 cases of our own, were analyzed clinicopathologically. RESULTS: Mucin-producing tumor of the pancreas was found in 177 males and 82 females (M:F = 2.2:1). The mean age was 65.5 years. Jaundice, diabetes mellitus and a past history of pancreatitis were found in 15%-19% of the cases. The tumor was most frequently (62%) found in the head of the pancreas. Pathologically, hyperplasia or adenoma was found in 58 cases, and adenocarcinoma in 160 cases. Five-year-survival rate by the Kaplan-Meier method was 82.6% in all of the cases and postoperative survival curve was much better in cases with this type of carcinoma than in cases with ordinary pancreatic duct cell carcinoma (5-year-survival rate: 82.6% vs 17.3%). Serum tumor markers such as CEA or CA 19-9 were not effective in differentiating between benign and malignant, or in determining the degree of cancerous spread, while cytology of the pancreatic juice and biopsy of the tumor could contribute to the diagnosis. CONCLUSIONS: Mucin-producing tumor has unique clinicopathological characteristics, such as the dilated main pancreatic duct or branches, dilatation of the orifice of the papilla of Vater, or good prognosis. Since a diagnosis for benign or malignant is very difficult in some cases, methods for distinguishing benign from malignant lesions or for determining cancerous spread, such as molecular biological techniques, should be established.

Adenocarcinoma, Mucinous↗

PubMedDate not supplied

A case of gallbladder cancer with para-aortic lymph node metastasis who has survived more than seven years after the primary extended radical operation.

A 55-year-old man with gallbladder cancer was surgically treated in our hospital in July 1988. The tumor was about 8 cm in diameter, replaced the entire gallbladder, and invaded the liver and the hepatoduodenal ligament. In addition, extensive tumor metastasis to lymph nodes, including those of the para-aortic area was noted (Stage IV). Extended cholecystectomy with resection of the liver and lymph node dissection were performed. Although all of the macroscopic tumors were removed surgically, we believed that the tumor would recur in the near future, since all of the excised para-aortic lymph nodes were involved by carcinoma histologically. After surgery, the patient received 5'-deoxy-5-fluorouridine (5'-DFUR) orally at a dose of 600 mg per day. In December 1993, more than 5 years after the primary operation, cancer recurrence in para-aortic lymph nodes was demonstrated by computed tomography (CT). In June 1994, the patient underwent a second operation for treatment of recurrent tumor. The lymph nodes firmly adhered to both the aorta and left renal vein, and could not be removed. Since August 1994, he has received external radiation therapy, and there has been no further enlargement of the nodes. This is the first reported case of gallbladder cancer with para-aortic lymph node metastasis who survived more than seven years after the primary extended radical operation with cholecystectomy, resection of the liver, and extended lymph node dissection.

Adenocarcinoma↗

PubMedDate not supplied

Subtotal resection of the head of the pancreas preserving duodenum and vessels of pancreatic arcade.

We reported a procedure of duodenum-preserving subtotal pancreatectomy of the pancreas according to the precise anatomy of the pancreatoduodenal region, especially of the pancreaticoduodenal arteries which provide blood to the duodenum. After a complete Kocher's maneuver is performed, the pancreas is cut above the portal vein and removed from the third portion of the duodenum, followed by the removal of the posterior surface of the pancreas head from a connective tissue membrane. The main pancreatic duct is identified at its junction with the terminal portion of the bile duct from the posterior surface of the head of the pancreas and is cut at the junction. The pancreas is cut in the line of the ASPD. The reason we leave the part of the pancreas between the auodenum, ASPD and the common bile duct is that the artery toward the papilla of Vater runs along the right side of the common bile duct and would be difficult to be preserved with the removal of this part of the pancreas. The most important techniques of this procedure is to keep the connective tissue membrane of the posterior surface of the pancreas intact so as to preserve pancreaticoduodenal arteries and veins. Benign lesions as well as lowgrade malignancy of the head of the pancreas may be possible indications for this procedure.

Angiography↗

PubMedDate not supplied

Histologic differences between flat tubular colorectal neoplasias in Japan and Sweden.

A total of 231 flat colorectal neoplasias were investigated at two disparate geographical regions (Stockholm and Tokyo). Of the 141 flat neoplasias seen in Tokyo, 24.8% had HGD, 7.0% intramucosal carcinoma and 9.9% invasive carcinoma. On the other hand, of the 90 flat mucosal neoplasias seen in Stockholm, 13.3% had HGD, 1.1% intramucosal carcinoma and 1.1% invasive carcinoma. The differences between flat adenomas with HGD, intramucosal carcinomas and invasive carcinomas in Japanese patients were significantly higher (p < 0.001) than in Swedish patients. While the causes responsible for this geographic difference remains unclear, possible influences of ethnicity and/or of environmental factors were advanced.

Adenoma↗

PubMedDate not supplied

Appleby operation for carcinoma of the body and tail of the pancreas.

Long-term survival of carcinomas in the body and tail of the pancreas after surgery is still rare. One of the major reasons for unresectability is cancerous invasion to major vessels, such as the common hepatic and splenic arteries. Resection of the involved arteries can increase resectability and thus might increase post-operative survival. The aim of this study was to clarify the importance of the Appleby operation for carcinoma of the body and tail of the pancreas. A Case Report was carried out with a 54 year-old man, had suffered back pain and loss of body weight for six months. Imaging procedures such as US, CT or angiography showed a carcinoma in the body of the pancreas, about 3 cm in size, and both the common hepatic and splenic arteries were invaded by the tumor. The Appleby operation was used for this patient, since firstly there was no invasion to the head of the pancreas, secondly neither the proper hepatic artery nor the SMA was involved, thirdly the root of the CA was free of carcinoma, and finally because clear pulsation of the proper hepatic artery could be felt one or two minutes after occlusion of the CHA, which indicated that resection of the CHA would not lead to hepatic ischemia. The postoperative course was uneventful. His appetite recovered well and his body weight increased to the level before the disease. The patient was relieved from back pain and has returned to work 18 months after the operation, although he had a local recurrence eight months after the operation. In addition, eleven cases with carcinoma of the body and tail of the pancreas were used for a literature review. The average survival time after the Appleby operation is 6.6 months, and four patients are still alive. One patient has survived 13 years after the operation. It was concluded that although the prognosis after Appleby procedure is still not satisfactory that this operation can at least offer patients a better quality of life.

Back Pain↗

PubMedDate not supplied

Transthoraco-phrenic esophageal transection with paraesophago-gastric devascularization and splenectomy using a stapler.

BACKGROUND/AIMS: Surgery remains the most reliable treatment for bleeding esophageal varices. The aim of this study was to introduce the operative technique of transthoraco-phrenic esophageal transection with paraesophagogastric devascularization using a stapler and to evaluate surgical results. METHODS: Forty-five patients underwent the procedure; an elective procedure was performed in 22 patients (bleeders) and a prophylactic procedure in 23 patients (nonbleeders). Twenty-nine patients were classified as Child's A, 15 as B and 1 as C. Previous sclerotherapy had been performed in 5 patients. RESULTS: No hospital deaths occurred. No patients developed postoperative anastomotic leakage, encephalopathy, or any complications related to phrenicotomy. Three patients bled postoperatively from recurrent esophageal varices. Cumulative 5-year bleeding rates were 5.0% in bleeders and 6.6% in non-bleeders. Two patients died due to bleeding varices. Cumulative 5-year survival rates were 72.1% and 78.8% in patients classified as Child's A and Child's B, respectively. CONCLUSIONS: This procedure may be indicated for a majority of Child's A or B patients. Although the advantages of this procedure must be evaluated further, it may be an alternative when injection sclerotherapy and endoscopic ligation fail.

Adult↗

PubMedDate not supplied

Intra-operative diagnosis of N2 lymph node metastasis of gastric cancer.

BACKGROUND/AIMS: Limited lymph node dissection for gastric cancer, which is prevalent in Western countries, leaves cancer cells in the second tier of nodes in patients who have metastasis in those nodes. It is, however, difficult to correctly diagnose nodal status during surgery. The present study was, therefore, designed to examine how to detect N2 metastasis intra-operatively. METHODOLOGY: Five hundred and eight patients undergoing extended lymph node dissections for gastric cancer were retrospectively analyzed. Accuracy of the intraoperative diagnosis of node involvement based on macroscopic findings was investigated, according to the N stage and histological type of the tumor. Furthermore, the distributions of N2 metastasis were clarified, according to tumor site. RESULTS: Intra-operative macroscopic findings were frequently assessed as being less severe than histological findings in cases with N2 metastasis (61.9%, 39/63). Intra-operative recognition of N2 metastasis was significantly lower in the cases with undifferentiated adenocarcinoma (28.2%, 11/39) than in those with differentiated adenocarcinoma (56.5%, 13/23). The distributions of N2 metastasis revealed nodes along the left gastric and common hepatic arteries to be the key junctions for lymphatic flow from the middle and lower thirds of the stomach, respectively. CONCLUSIONS: Intra-operative diagnosis of N2 metastasis is difficult to make based on macroscopic findings, especially in undifferentiated tumors. To detect N2 metastasis intra-operatively, the nodes along the left gastric or common hepatic artery should be submitted to frozen section examination for primary tumors located in the middle or lower third of the stomach, respectively.

Adenocarcinoma↗

PubMedDate not supplied

Bile duct carcinoma without jaundice: clues to early diagnosis.

BACKGROUND/AIMS: Most bile duct carcinomas are diagnosed at an advanced stage, after the appearance of jaundice. The features of bile duct carcinomas without jaundice were analyzed with the aim of allowing early diagnosis in such cases. METHODOLOGY: Clinicopathological features, images and surgical outcomes were compared between 18 non-jaundiced and 85 jaundiced patients with extrahepatic bile duct carcinoma. RESULTS: Among the non-jaundiced patients, 13 were symptomatic. Abnormalities on hepatic function and tumor marker tests were seen in 56% and 44%, respectively. In all 18 cases, ultrasonography demonstrated biliary abnormalities including masses (9 patients) and strictures (5 patients). The diagnosis was confirmed histologically by transpapillary bile duct biopsy in eight of 10 non-jaundiced patients. The non-jaundiced patients (83%) had a higher rate of resectability than jaundiced patients (58%). Pathological findings of resected specimens showed no significant differences between the two groups. The non-jaundiced group had a significantly higher survival rate than the jaundiced group: 50% vs. 22% at 5 years. CONCLUSION: For early diagnosis of bile duct carcinomas not associated with jaundice, detailed ultrasonographic examination is useful, and subtle changes indicate a need for direct cholangiography. Non-jaundiced cases have the potential for curative resection.

Bile Duct Neoplasms↗

PubMedDate not supplied

Results of extended lymph node dissection for gastric cancer cases with N2 lymph node metastasis.

The therapeutic value of extended lymph node dissection (D2) for gastric cancer remains controversial. Limited lymph node dissection, however, leaves cancer cells in the second tier of nodes (N2) in patients with N2 metastasis. This retrospective study was, therefore, undertaken to clarify which patients would be most likely to benefit from D2 dissection, even with N2 metastasis. Two groups, N2 cases with (n = 40) and without (n = 24) the development of recurrence after curative surgery, were compared. Borrmann type IV and serosal invasion were significantly related to recurrence. The number of metastatic nodes did not differ significantly between the two groups. All (7/7) of the Borrmann type IV cases with N2 metastasis developed recurrence and died. However, one quarter (7/30) of the cases with serosal invasion and N2 metastasis showed no sign of recurrence. D2 dissection is a surgical treatment which offers the potential to cure gastric cancers, other than Borrmann type IV tumor, with N2 metastasis.

Female↗

PubMedDate not supplied

Dihydropyrimidine dehydrogenase but not thymidylate synthase expression is associated with resistance to 5-fluorouracil in colorectal cancer.

BACKGROUND/AIMS: In planning adjuvant treatment of colorectal cancer, it is of critical importance to optimize the treatment by identifying subsets of patients that will respond or not to chemotherapy. Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) are key enzymes involved in the biochemical functions of the antimetabolite 5-fluorouracil (5-FU). In searching for the factors determining the 5-FU sensitivity of colorectal cancer, TS and DPD were analyzed in relation to the inhibitory effect of 5-FU on cell proliferation in a series of human colorectal cancer cell lines. METHODOLOGY: TS and DPD protein expressions were quantified in 5 human colorectal cancer cell lines, using TS binding assay and Western blotting, respectively. Cellular growth inhibition was assessed by MTT assay after 48 hours of continuous exposure to 5-FU or cisplatin (CDDP). RESULTS: TS protein expression was detected in all but one of the cell lines studied and varied within a 17-fold range, while DPD protein expression was detectable in only one cell line (CaR1). CaR1, which expressed the highest level of DPD and no detectable TS, showed remarkable resistance to 5-FU. The other colorectal cancer cell lines with undetectable DPD expression were sensitive to 5-FU. There was no correlation between TS expression and 5-FU sensitivity. All of the cell lines studied showed similar sensitivity to CDDP. CONCLUSIONS: These data suggest that DPD, but not TS, expression predicts 5-FU sensitivity in colorectal cancer cell lines.

Antimetabolites, Antineoplastic↗