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Biomedical subjects

M Suyama

Publications and source records attributed to M Suyama.

68 records · Page 4Linked to original sources
PubMed1984

Production of serotonin by a transplantable strain of histamine-producing primary gastric carcinoid of Mastomys natalensis.

Two biochemically distinguishable transplantable tumor strains (A and B) were established from a primary gastric carcinoid of Mastomys secreting histamine alone. Strain A in the third generation acquired a new ability to produce serotonin [5-hydroxytryptamine (5-HT)] and retained endocrine activities to produce both histamine and 5-HT through the following subpassages, whereas strain B (like the primary tumor) continued to produce histamine alone. The findings were further supported by the immunohistochemical demonstration of 5-HT-containing tumor cells in strain A after generation 3 and the absence of such cells in strain B and also by the ultrastructural demonstration of tumor cells containing pleomorphic secretory granules in strain A after the third generation but not in strain B. Sixteen samples of Formalin-fixed, paraffin-embedded primary gastric carcinoids of Mastomys were stained by the same immunohistochemical method for 5-HT detection. The positively stained tumor cells were demonstrated in 4 tumor samples, though they were scantily distributed in tumor parenchyma except for 1 metastasizing tumor. 5-HT-producing tumor cells appeared through many proliferative cycles of the deranged histamine-producing cells. The endocrinologic similarity was noted between this transplantable tumor strain and a specific type of gastric carcinoid in humans, and the possible histogenesis of the latter tumor was discussed on the basis of data obtained from the present transplantation experiments.

Animals↗
PubMed1984

Novel flushing provoked by volatile anesthetics in Mastomys natalensis bearing a transplantable substrain of gastric carcinoid that predominantly secretes serotonin.

A tumor substrain secreting a large amount of serotonin [5-hydroxytryptamine (5-HT); CAS: 50-67-9; 3-(2-amino-ethyl)indol-5-ol] and a minute amount of histamine (CAS: 51-45-6) has been isolated from the previously established strain of transplantable gastric carcinoid of Mastomys (Praomys) natalensis secreting both histamine and 5-HT. Mastomys bearing a large growing transplant and excreting a large amount of 5-hydroxy-indoleacetic acid [(5-HIAA) CAS: 54-16-0] were associated often with reddening of the nose, lower lip, auricles, hands, and feet. Soon after the animals were anesthetized by ether or other volatile anesthetics, the tinges of red of the above-mentioned exposed parts abruptly turned bright red and rapidly spread over the neck, upper chest, and epigastric area. The reddening was transient, lasting 1.5-5 minutes, thereby fulfilling the criteria of flushing. The severity of ether-provoked flushing in tumor-bearing Mastomys paralleled the urinary excretion levels of 5-HIAA. The ether-provoked flushing was prevented completely by sc injection of either ketanserin (150 micrograms) or somatostatin (20 micrograms). The same ether-provoked flushing as found in tumor-bearing Mastomys could be reproduced in normal ones by constant infusion of 20 mg 5-HT/kg/24 hours (i.e., doses comparable to those released from a transplanted tumor) through an osmotic minipump implanted subcutaneously.

Anesthetics↗
PubMed1983

[Problems of early diagnosis of pancreatic cancer and evaluation of various morphological studies].

Clinical symptoms and abnormality of laboratory examinations in 62 patients with proven pancreatic carcinoma were studied. The following indications for detailed examination of the pancreas have been evolved: (1) vague abdominal symptoms, (2) jaundice, (3) abnormalities of laporatory examinations including serum LAP, ALP, amylase and cholinesterase level, and abnormal GTT. In the jaundiced patient the initial examination is US followed by PTCD to relieve the jaundice, and then angiography to assess resectability of the tumor. In the non-jaundiced patient US is used as a screening procedure. Should this be abnormal a lesion may be confirmed by CT. If not ERCP is indicated when there is some distinct reason to suspect pancreatic disease. If ERCP reveals abnormality then angiography is performed to determine whether the lesion is benign or malignant, and if malignant it is resectable or not. In the period of 1968 and 1981, 112 proven pancreatic carcinomas were studied. Overall resectability was 26%. Thirty tumors were less than 3 cm and the smallest lesion measured 1.2 cm.

Angiography↗
PubMed1981

Operative procedure and indications for surgical management of pulmonary metastasis of choriocarcinoma.

From 1961 to 1977, thoracotomy was performed on 19 patients with pulmonary metastasis of choriocarcinoma in Nagoya University with regard to the role of thoracotomy in management of pulmonary metastasis of choriocarcinoma. Our surgical indications for the disease are: 1) the patients must be a good risk for surgical intervention. 2) The primary malignancy be controlled. 3) Evidence of pulmonary metastasis be limited to the lung. 4) The urinary human chorionic gonadotropin (hCG) titers should be controlled at low levels below 1000 mIU/ml by preoperative chemotherapy. At levels below 200 mIU/ml, the indication for surgery will be assessed by the cellular response to chemotherapeutic agents. As an operative procedure, in view of a low incidence of lymph nodes metastases, extended pulmonary surgery appears to be unnecessary providing that the gross pulmonary lesion is removed by partial resection of the lung or lobectomy. Postoperative adjuvant chemotherapy is required to induce a complete remission of the choriocarcinoma.

Adult↗
PubMed1980

Esophageal cyst, a case report and a review of the literature.

The esophageal cyst is a rare disease only 20 cases of which have been reported in the literature in Japan. We recently treated such a patient and at thoracotomy, we found the cyst to be located the submucosal layer of the esophagus. The cyst could be easily extirpated and the patient made an uneventful recovery. Gross findings revealed thick, yellow and mucus-like contents inside the cyst. Microscopically, the cyst was lined with ciliated columnar epithelium and there was no evidence of cartilage. The 21st such occurrence in Japan is reported herein and a discussion is made of related literature.

Aged↗
PubMedDate not supplied

The detection and prognosis of small pancreatic carcinoma.

During a period of 16 years, 203 proven pancreatic ductal adenocarcinomas were studied. Tumor size was measured on either the resected or the autopsy specimen. Four tumors were smaller than 1 cm, and 17 tumors were between 1.1 and 2 cm. ERCP has been found to be the most accurate in the diagnosis of small pancreatic carcinoma. Followup of 44 patients in whom the tumor was resected showed that survival depended on tumor size. In four patients with tumors smaller than 1 cm without parenchymal invasion, the postoperative 5-yr cumulative survival rate was 100%. Pancreatic carcinoma smaller than 1 cm limited to duct epithelium is considered as early cancer. Various diagnostic imaging modalities are now available to evaluate patients in whom pancreatic carcinoma is clinically suspected. These include ultrasonography (US), computed tomography (CT), endoscopic retrograde cholangiopancreatography (ERCP), and angiography. More recently magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), and peroral pancreatic ductal biopsy also have been used. This report compares diagnostic modalities for pancreatic carcinoma in order to provide a data base for their rational use in the diagnosis of small resectable pancreatic carcinomas.

Adult↗
PubMedDate not supplied

Management of branch duct-type intraductal papillary mucinous tumor of the pancreas based on magnetic resonance imaging.

BACKGROUND: We assessed the usefulness of magnetic resonance imaging (MRI) in identifying nonmalignant intraductal papillary mucinous tumors (IPMTs) of the pancreas. METHODS: Thirty-three patients with branch duct-type IPMT diagnosed by endoscopic retrograde cholangiopancreatography were prospectively examined with magnetic resonance cholangiopancreatography followed by dynamic gadolinium-enhanced MRI examinations, and patients with no findings suggestive of malignancy, including a solid mass, mural nodules, a main pancreatic duct wider than 5 mm in diameter, and stenosis of the main pancreatic duct, were prospectively followed up with sequential MRI examinations once or twice a year. RESULTS: Twenty-six (79%) patients showed no findings suggestive of malignancy in the initial MRI examination. The diameter (mean +/- standard error) of the main pancreatic duct was 3.9 +/- 0.7 mm and that of the ectatic branch pancreatic duct was 36.0 +/- 9.1 mm. Twenty-three patients were prospectively followed for more than 36 months and 22 of them showed no findings suggestive of malignancy during follow-up periods ranging from 39 to 77 months (mean = 55 months). CONCLUSION: MRI was useful to identify nonmalignant IPMTs of the branch duct type, and close follow-up observation with serial MRI examinations may be appropriate in the management of such patients.

Adenocarcinoma, Mucinous↗
PubMedDate not supplied

Endoscopic ultrasound and intraductal ultrasound in the diagnosis of small pancreatic tumors.

BACKGROUND: The purpose of this study was to assess the diagnostic value of endoscopic ultrasound (EUS) and intraductal ultrasound (IDUS) in the detection of small pancreatic tumors. METHODS: EUS was performed in 166 patients with verified pancreatic disease. IDUS was performed in 46 patients. A microprobe was introduced into the main pancreatic duct through the papilla of Vater using the duodenoscope. RESULTS: EUS was valuable in the detection of small pancreatic tumors. Ductal adenocarcinomas smaller than 1 cm were demonstrated as a hypoechoic mass with a central irregular hyperechoic area. EUS and IDUS were useful in the characterization of intraductal paillary tumors (ductectatic mucinous tumors). EUS demonstrated nodular excrescences, and IDUS depicted papillary proliferation of the duct epithelium, which are characteristic of carcinomas and adenomas but not of hyperplasia. Internal architecture of cystic neoplasms was clearly depicted by EUS, and differentiation of serous and mucinous tumors was readily achieved. A tumor as small as a 5-mm islet cell was demonstrated on EUS because islet cell tumors are very hypoechoic. CONCLUSION: EUS and IDUS are relatively noninvasive procedures and are useful in the detection of small tumors and differentiation of pancreatic diseases.

Adenocarcinoma, Papillary↗
PubMedDate not supplied

5-fluorouracil continuous infusion combined with cisplatin for advanced pancreatic cancer: a Japanese Cooperative Study.

BACKGROUND/AIMS: The prognosis of patients with advanced pancreatic cancer is extremely poor. To improve their prognosis, providing effective chemotherapy is necessary. The aim of this study was to evaluate the anti-tumor activity and toxicity of combined chemotherapy (FP therapy) using 5-fluorouracil and cisplatin in Japanese chemo-naive patients with advanced pancreatic cancer. METHODOLOGY: Thirty-seven previously untreated patients with histologically proven pancreatic adenocarcinoma were treated with FP therapy. 5-fluorouracil was administered at 500 mg/m2/day by continuous intravenous infusion for 5 days and cisplatin was administered at 80 mg/m2 intravenously on the 1st day. Therapy was repeated every 4 weeks until there was evidence of disease progression or unacceptable toxicity. RESULTS: Three patients achieved partial responses, whereas none exhibited a complete response. The overall response rate was 8% (95% confidence interval, 2-22%) and the response durations were 6, 9 and 12 months, respectively. The median survival time of patients was 5 months. Toxicities were generally mild and acceptable, although nausea/vomiting was the most commonly observed toxicity. CONCLUSIONS: FP therapy on this schedule had limited anti-tumor activity for pancreatic cancer, indicating that, practically, it should not be performed in Japanese patients with advanced pancreatic cancer.

Adenocarcinoma↗