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K Koito

Publications and source records attributed to K Koito.

At least 37 records · Page 2Linked to original sources
PubMed1998

Assessing the suitability of gastric carcinoma for limited resection: histologic differentiation of endoscopic biopsy.

Histologically differentiated adenocarcinoma satisfies one of the criteria for limited surgery for mucosal carcinoma of the stomach: however, the histology of the endoscopic biopsy specimen is often different from that of the resected specimen. The medical records of 1018 early gastric carcinomas were retrospectively analyzed to investigate the relation between the histologies of biopsy and resected specimens. Regression analysis showed that the histologies of biopsy specimens were significantly related to those of resected specimens (r = 0.677, n = 5, p = 0.0288) for the mucosal carcinomas, but their relation was not significant for the submucosal carcinomas (r = 0.677, n = 5, p = 0.2091). By analyzing the 344 differentiated mucosal carcinomas, moderately differentiated tubular adenocarcinomas were seen to be frequently less differentiated at resection. The histology of the biopsy specimens from mucosal carcinoma of the stomach grossly satisfies one of the criteria for limited surgery, but moderately differentiated adenocarcinoma may not be suitable for this treatment.

Adenocarcinoma↗
PubMed1998

Tumor recurrence following resection for early gastric carcinoma and its implications for a policy of limited resection.

Some patients suffer postoperative recurrence after curative resection of early gastric carcinoma. This study reviewed consecutive patients with a single primary lesion and analyzed the relation between the pathologic findings and recurrence of early gastric carcinomas for determining indications for limited surgery. Among the 1585 consecutive patients with a solitary primary lesion of an early gastric carcinoma who had undergone curative surgery between 1963 and 1989 at one general hospital, pathologic findings relating to recurrence were analyzed according to Japan's General Rules for Gastric Cancer Study in Surgery and Pathology. Of these carcinomas, mucosal carcinomas comprised 701 (44.2%) and submucosal ones 884 (55.8%). The total recurrence rate in this series was 1.0%. Submucosal carcinomas (1.6%) were significantly (p < 0.02) more recurrent than mucosal ones (0.29%). Of the 16 patients with recurrence, 10 (62.5%) died within 5 years after surgery, frequently because of blood-borne metastasis. Macroscopically elevated components, the degree of histologic differentiation, and lymph node metastasis significantly contributed to the postoperative recurrence. After detailed analysis of submucosal carcinomas, it is strongly suspected that carcinomas with a macroscopically elevated component were significantly associated with nodal involvement and microvessel invasion, and that these abnormalities lead to recurrence. Among the early gastric carcinomas, differentiated submucosal carcinomas with a macroscopically elevated component, lymph node metastasis, or both have the most potential of recurrence after surgery. Mucosal carcinomas must be restricted to limited surgery, but, blood-borne metastasis should be carefully avoided.

Adenocarcinoma, Mucinous↗
PubMed1998

Diagnosis and treatment of malignant lymphoma of the parotid gland.

BACKGROUND: To correlate the imaging and pathological features and to discuss therapeutic modalities and the prognosis of malignant lymphoma originating in the parotid gland, which is relatively rare. METHODS: The subjects were five patients with malignant lymphoma originating in the parotid gland. Three and two patients were stage I and stage II, respectively. CT examination was applied to all, whereas only one case was examined by MRI. All were treated with radiotherapy following surgery or chemotherapy. Three patients underwent combination chemotherapy, such as with MACOP-P or VEPA, following surgery. RESULTS: Although malignant lymphoma originating in the parotid gland is histologically described as low-grade non-Hodgkin's lymphoma, two and one of the cases were classified as intermediate and high grade in the present series, respectively. These three exhibited a tendency for infiltration into the adjacent tissue and tumor inhomogeneity in the imaging findings, suggesting a correlation with histologically intermediate or high-grade non-Hodgkin's lymphoma. It was successfully controlled by radiotherapy, with dosages ranging from 40 to 44 Gy. The patients were followed for 2-8 years. No relapse was found in the three patients with stage I. However, both stage II patients had relapses and were subjected to additional radiotherapy combined with chemotherapy. Since then, no tumor relapse has been noted at either this or other sites. CONCLUSIONS: Malignant lymphoma including intermediate or high grade originating in the parotid gland indicated satisfactory prognosis following radiotherapy and chemotherapy.

Aged↗
PubMed1998

Mucoepidermoid carcinoma of the larynx: a case which responded completely to radiotherapy and a review of the literature.

Most laryngeal cancers are squamous cell carcinomas, and adenocarcinomas account for < 1% of cancers of the larynx. Among them, mucoepidermoid carcinoma is extremely rare and there is little agreement about the treatment of this carcinoma. We encountered one patient with mucoepidermoid carcinoma of the bilateral vocal cords (T1bN0M0, Stage 1). For this, most investigators recommended a surgical procedure. However, because of his old age, the early stage and low grade of histopathology, we treated this patient with radiotherapy alone, delivered by accelerated hyperfractionation, which is a more effective strategy for treating radioresistant tumors than conventional irradiation. Following radiotherapy, the tumor disappeared and the patient has been alive and well for more than six years. An old patient with mucoepidermoid carcinoma of the larynx was successfully treated with radiotherapy alone.

Aged↗
PubMed1998

Mucin-producing pancreatic tumors: comparison of MR cholangiopancreatography with endoscopic retrograde cholangiopancreatography.

PURPOSE: To compare magnetic resonance cholangiopancreatography (MRCP) with endoscopic retrograde cholangiopancreatography (ERCP) in the detection of mucin-producing pancreatic tumors. MATERIALS AND METHODS: The authors retrospectively reviewed MRCP and ERCP images obtained in 28 patients with mucin-producing pancreatic tumors. Detectability of the pancreatic duct and its branches, intraductal cystic lesions, and intracystic nodules or septa was assessed. RESULTS: MRCP depicted cystic dilated ductal branches significantly better than did ERCP (P < .001). The difference in the number of nodules or septa detected with MRCP compared with ERCP was not significant. MRCP, however, simultaneously showed not only the main pancreatic duct but also the cystic lesions; this was not always possible with ERCP. CONCLUSION: MRCP appears to be more effective and less invasive than ERCP to evaluate changes in the size and extent of tumors and to determine if new lesions appear, as well as to follow up mucin-producing pancreatic tumors.

Adenocarcinoma, Papillary↗
PubMed1998

Differential diagnosis of small hepatocellular carcinoma and adenomatous hyperplasia with power Doppler sonography.

OBJECTIVE: The aim of this study was to compare the ability of power Doppler sonography and color Doppler sonography to differentiate hepatocellular carcinoma (HCC) from adenomatous hyperplasia (AH). SUBJECTS AND METHODS: In 48 patients with cirrhosis of the liver, color Doppler sonography and power Doppler sonography were performed on 53 hepatic nodules smaller than 20 mm in diameter (32 nodules were HCC; 21 nodules were AH). We evaluated the detectability of the pulsatile and continuous flows in the nodules at each hepatic segment. RESULTS: Thirty-four percent of nodules produced color signal on color Doppler sonography; 77%, on power Doppler sonography (p < .01). The identification rate of nodules in the left lateral segment was significantly lower than in other segments. Continuous flow was seen in the nodules of both HCC and AH. However, only in HCC did we see pulsatile flow. For HCC, pulsatile flow was seen with color Doppler sonography in 25% of the nodules smaller than 10 mm in diameter and in 50% of the nodules between 10 and 20 mm. With power Doppler sonography, pulsatile flow was seen in 67% (p < .05) of the nodules smaller than 10 mm and in 90% (p < .01) of the nodules between 10 and 20 mm. Sensitivity and negative predictive value in the differentiation of HCC from AH were significantly higher with power Doppler sonography than with color Doppler sonography (81% versus 41%, respectively, for sensitivity and 78% versus 53%, respectively, for negative predictive value). Specificity, positive predictive value, and efficacy of both color Doppler sonography and power Doppler sonography were 100%, 100%, 60%, respectively. CONCLUSION: On the basis of our results, power Doppler sonography is more sensitive than color Doppler sonography in revealing small HCC and in differentiating HCC from AH under physiologic hemodynamic conditions.

Aged↗
PubMed1998

[Clinical assessment of contrast-enhanced ultrasonography for the diagnosis of gall bladder diseases].

We evaluated the efficacy of contrast-enhanced ultrasonography (CEUS) with intra-arterial injection of CO2 microbubbles in 37 cases of gall bladder diseases. CEUS clearly visualized arterial flow and vascularity in every lesions without debris and gave us the precise information of vascular structure for the differential diagnosis of gall bladder tumors. For example, highly bifurcated tumor vessels and strong enhancement was observed in gall bladder cancer and we could detect relatively strong enhancement along the lumen with lack of enhancement of Rokitansky-Aschoff sinus in localized-type adenomyomatosis. Though CEUS is now an invasive modality, it will enable us to understand the non-invasive modality such as color doppler imaging with intra-venous administration of microbubbles in the future.

Carbon Dioxide↗
PubMed1997

Solitary cystic tumor of the pancreas: EUS-pathologic correlation.

BACKGROUND: It is clinically important to distinguish neoplastic from non-neoplastic pancreatic cysts. METHODS: Retrospective correlations were made between pathologic and EUS data from 52 pancreatic solitary cystic tumors: mucinous cystadenoma (10), mucinous cystadenocarcinoma (7), serous cystadenoma (5), ductectatic mucinous cystic tumor (10), solid and papillary epithelial neoplasm (5), and non-neoplastic cyst (15). The mean tumor size was 3.5 cm (range, 1.2 cm to 6.0 cm). RESULTS: Six classifications of the internal structures of these cysts were developed: thick wall type, tumor protruding type, thick septal type, microcystic type, thin septal type, and simple type. Although all neoplastic cysts belonged to the first four types, all non-neoplastic cysts belonged to the last two types. The accuracy of EUS for differentiating tumors was estimated at 96% and 92%, respectively, by two observers. CONCLUSIONS: EUS may become a mandatory modality for differentiating pancreatic solitary cystic tumors and choosing an optimal treatment.

Adenocarcinoma↗
PubMed1997

Inflammatory pancreatic masses: differentiation from ductal carcinomas with contrast-enhanced sonography using carbon dioxide microbubbles.

OBJECTIVE: The aim of this study was to evaluate the clinical efficacy of contrast-enhanced sonography using carbon dioxide microbubbles to differentiate inflammatory pancreatic masses from ductal carcinomas of the pancreas. SUBJECTS AND METHODS: Fifty-five patients, including 35 patients with ductal carcinomas and 20 with inflammatory pancreatic masses, underwent contrast-enhanced sonography, CT, and digital subtraction angiography (DSA). Carbon dioxide microbubbles were prepared by mixing 10 ml of carbon dioxide and the same amount of 25% soybean oil vigorously. Carbon dioxide microbubbles were injected through an angiographic catheter that was placed in the celiac axis. Vascularity of the tumors as determined by those three techniques was interpreted by three physicians who had no knowledge of the pathologic results. RESULTS: Contrast-enhanced sonography was best at revealing tumor vascularity among the three techniques. On contrast-enhanced sonography, 19 (95%) of the 20 inflammatory pancreatic masses were isovascular and 32 (91%) of the 35 ductal carcinomas were hypovascular. In contrast, the isovascularity of inflammatory masses was five (25%) on CT, and two (10%) on DSA, respectively. The sensitivity and accuracy rate of differentiating both diseases on contrast-enhanced sonography were 98% and 95%, respectively; on CT, they were both 73%; and on DSA they were both 67%. From our results, an isovascular mass is probably an inflammatory mass, whereas a hypovascular mass is most likely a ductal carcinoma on contrast-enhanced sonography. CONCLUSION: Contrast-enhanced sonography can help differentiate an inflammatory pancreatic mass from a ductal carcinoma.

Adenocarcinoma↗
PubMed1997

Diagnostic features on images in primary small cell carcinoma of the pancreas.

Small cell carcinoma of the pancreas is a rare tumor with very poor prognosis, but the tumor is successfully treated by chemotherapy. Therefore, small cell carcinoma must be differentiated from other pancreatic tumors on images. A 71-year-old man presented with digestive symptoms. Multiple hypoechoic masses were detected on transabdominal ultrasonography and lateral shadow and posterior echo enhancement on endoscopic ultrasonography. The dynamic computed tomography scan revealed that the tumor walls were hypervascular at an early phase, and that the central portions were gradually stained at a late phase with differences among the tumors; tumor stains were also found on angiography. The distal site of the main pancreatic duct was completely interrupted, as seen on endoscopic retrograde pancreatography. The resected specimens were composed of circumferential hard walls and internally necrotic, hemorrhagic contents of different degrees and were microscopically diagnosed as small cell carcinoma. The tumor has to be differentiated from hypervascular pancreatic tumors, especially islet cell tumors.

Aged↗
PubMed1996

General pattern of lymph node metastasis in early gastric carcinoma.

A reliable method for recognizing lymph node metastasis is indispensable for the attending physician to recommend less extensive treatment for early gastric carcinoma. Here we review 1137 consecutive patients with a single primary lesion, and the incidence and distribution of nodal involvement were investigated for correlations with pathologic findings. The overall incidence of metastasis was 9.5%: 2.6% for mucosal and 16.5% for submucosal carcinomas, a significant difference. The occurrence of metastasis was highest for lesions of the macroscopically mixed type, microscopically diffuse type, and large size. The involved nodes were most frequently found in the perigastric nodes along the lesser and greater curvatures, and it was well correlated with the tumor location, macroscopically depressed/mixed type, cancer depth, and histology. The diffuse-type carcinomas were most likely to metastasize to distant nodes. The distribution of involved nodes for early gastric carcinoma was similar to that for advanced carcinoma, as previously been reported. The submucosal carcinomas in this series had no indications for less extensive treatment, such as endoscopic or laparoscopic limited surgery. These carcinomas should be subject to standard surgery with gastrectomy and combined dissection of lymph nodes, especially node stations 1 and 3 to 8. The mucosal carcinomas sometimes involved the perigastric nodes, and such cases underwent gastrectomy and lymphadenectomy of node stations 1 and 3 to 7. Mucosal carcinomas 10 mm or less in size were negative for lymph node metastasis and were considered appropriate for less extensive treatment.

Carcinoma↗
PubMed1996

Balloon-occluded retrograde transvenous obliteration for gastric varices with gastrorenal or gastrocaval collaterals.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of balloon-occluded retrograde transvenous obliteration for gastric varices with gastrorenal or gastrocaval collaterals. SUBJECTS AND METHODS: Thirty patients who had gastric varices with gastrorenal or gastrocaval collaterals underwent balloon-occluded retrograde transvenous obliteration. A 5-French balloon catheter was inserted in the gastrorenal collateral, gastrocaval collateral, or both, and a 5% solution of ethanolamine oleate iopamidole that contained equal amounts of ethanolamine oleate and iopamidole 300 was injected into the gastric varices. One day, 1 week, and 1 month after balloon-occluded retrograde transvenous obliteration, hepatic and renal function tests (total bilirubin, transaminase, blood ammonia, serum creatinine, and blood urea nitrogen) were done. To evaluate therapeutic efficacy, we observed the site with endoscopy every 2 weeks and obtained enhanced CT scans every month. The observation time ranged from 10 to 30 months. RESULTS: After balloon-occluded retrograde transvenous obliteration, gastric varices disappeared completely in all 30 cases in 4-16 weeks (mean, 10 weeks). Recurrence of gastric varices was observed in three cases (10%), which were treated with repeated balloon-occluded retrograde transvenous obliteration. Esophageal varices were aggravated in three patients (10%), who underwent successful endoscopic injection sclerotherapy. Complications of balloon-occluded retrograde transvenous obliteration were fever and hemoglobinuria, which disappeared in about 5 days. We observed no significant hepatic and renal functional damage. CONCLUSION: Balloon-occluded retrograde transvenous obliteration offers good control of gastric varices with gastrorenal or gastrocaval collaterals, even if hepatic function is poor.

Ammonia↗
PubMed1996

Percutaneous transhepatic biliary drainage using color Doppler ultrasonography.

We performed percutaneous transhepatic biliary drainage using color Doppler ultrasonography to decrease the complications of percutaneous transhepatic biliary drainage. Thirty patients underwent this procedure. We performed this method after identifying the second and third branches of the intrahepatic bile ducts, including the portal and the hepatic veins. The success rate of percutaneous transhepatic biliary drainage using color Doppler ultrasonography was 100% with one puncture in 29 patients and with two punctures in only one patient. We never encountered severe complications, such as bleeding, infection, hemobilia, or pseudoaneurysm formation in the hepatic artery. This method was safer and easier than the usual method using B-mode ultrasonography only.

Aged↗
PubMed1996

Primary malignant melanoma of the esophagus: diagnostic value of endoscopic ultrasonography.

Primary malignant melanomas of the esophagus have been clinically diagnosed as exophytic tumors by esophagography and esophagoscopy. We first applied endoscopic ultrasonography to the tumors; the tumors were demonstrated as "submucosal tumors" and smooth-surfaced with clear margins, and their internal echo-architectures depended upon the tumor sizes. We consider the disease can be clinically diagnosed by the above three diagnostic modalities.

Aged↗