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T Yao

Publications and source records attributed to T Yao.

At least 235 records · Page 13Linked to original sources
PubMed1993

Hepatoid adenocarcinoma of the stomach. A clinicopathologic and immunohistochemical analysis.

BACKGROUND: The clinicopathologic and immunohistochemical features of the primary gastric hepatoid adenocarcinomas still remain unclear. METHODS: The authors evaluated 28 hepatoid adenocarcinomas (HC) of the stomach on the basis of characteristic histologic features resembling hepatocellular carcinoma, which were selected from the 7200 cases of primary gastric carcinoma in their files. Additionally, 22 alpha-fetoprotein (AFP)-positive adenocarcinomas without hepatoid features (APC) were also selected. RESULTS: The HC cases fell into the following two groups: HC with AFP-positive tumor cells (Group 1; 15 cases) and HC without AFP-positive cells (Group 2; 13 cases). Histologically, the glycogen granules and hyaline globules were common features in HC. The incidence of a venous invasion of HC (Groups 1 and 2) was higher than that of APC (Group 3). There were no significant differences among the three groups regarding clinical features, macroscopic features, and the incidence of lymphatic permeation. An immunohistochemical study showed that HC had differentiation into various directions. As for the advanced carcinomas, the 5-year survival rates of patients with HC (Groups 1 and 2) and those with APC (Group 3) were 11.9% (21.4%, 8.3%) and 38.2%, respectively. The prognosis of Group 1 was similar to that of Group 2, but was poorer than that of Group 3. CONCLUSIONS: The findings suggested that HC, as shown by its characteristic histologic features, had a poor prognosis whether producing AFP or not, and that HC should therefore be distinguished from AFP-positive carcinoma without hepatoid features.

Adenocarcinoma↗
PubMed1993

Diagnosis of primary early gastric lymphoma. Usefulness of endoscopic mucosal resection for histologic evaluation.

BACKGROUND AND METHODS: Eight patients thought to have primary early gastric lymphoma were studied to evaluate the usefulness of endoscopic mucosal resection for the diagnosis of reactive lymphoid hyperplasia (RLH) or malignant lymphoma. RESULTS: In these patients, conventional endoscopic forceps biopsy did not provide a definite histologic diagnosis. Endoscopic ultrasonography (EUS) demonstrated that the disease was limited to the mucosa and the submucosa in all patients, without any paragastric lymph node involvement, so endoscopic mucosal resection was performed to obtain specimens large enough to include the submucosa. As a result, primary early gastric lymphoma was diagnosed in five patients, for whom subsequent gastrectomy confirmed the diagnosis. CONCLUSIONS: The authors recommend that endoscopic mucosal resection be performed in patients thought to have primary early gastric lymphoma and for whom a definite diagnosis can not be made by conventional endoscopic forceps biopsy.

Adult↗
PubMed1993

Neoplastic transformation arising in Peutz-Jeghers polyposis.

PURPOSE AND METHODS: To clarify the potential for malignancy of Peutz-Jeghers polyposis, we investigated 75 gastrointestinal polyps resected surgically or endoscopically from seven patients with this syndrome. RESULTS: There were 19 polyps in the stomach, 18 in the duodenum, 22 in the small intestine, and 16 in the large intestine, and these were histologically composed of 1 pyogenic granuloma, 1 cancer in adenoma, 2 adenomas, and 71 Peutz-Jeghers polyps. Nine of these Peutz-Jeghers polyps were accompanied by an adenomatous component, and, in addition, two of these showed a cancerous transformation with stalk invasion. A total of 12 neoplastic polyps (16 percent) were found in three relatively young patients (aged 20, 25, and 43 years), all of which were pedunculated and located either in the duodenum or in the jejunum. There was no statistical significance in size between the neoplastic polyps (mean +/- SD, 20.1 +/- 10.8 mm) and the completely hamartomatous polyps (mean +/- SD, 15.8 +/- 9.0 mm). Moreover, the configuration of these types of polyps seemed similar. CONCLUSION: Neoplastic transformation is not a rare event, and our results may indicate evidence of a hamartoma-adenoma-carcinoma sequence in Peutz-Jeghers polyposis.

Adolescent↗
PubMed1993

Significance of pericryptal fibroblasts in colorectal epithelial tumors: a special reference to the histologic features and growth patterns.

We analyzed the appearance of pericryptal fibroblasts (PCFs) identical to myofibroblasts in human colorectal epithelial tumors (adenomas, carcinomas) by an immunohistochemical method, with special reference to the histologic features and tumor growth patterns. The majority (61.5%) of adenomas contained well-developed PCFs. In contrast, carcinomas contained more poorly developed PCFs than adenomas. Approximately one third (35.4%) of the intramucosal and most (89.6%) of the submucosal carcinoma components had poorly developed PCFs. Pericryptal fibroblast development in pure carcinomas also was evaluated in association with two types of tumor growth patterns: polypoid growth carcinoma (PG-Ca) and nonpolypoid growth carcinoma (NPG-Ca). Polypoid growth carcinoma tended to contain well-developed PCFs, whereas NPG-Ca tended to lack PCFs. From the above findings, it is suggested that PCFs gradually decrease in the sequence of adenoma, intramucosal carcinoma, and submucosal invasive carcinoma. In addition, the two growth types (PG-Ca and NPG-Ca) are histologically different in PCF development, and the lack of a PCF network in NPG-Ca seems to be the reason why NPG-Ca can invade the submucosa more easily than PG-Ca, which has a consistent PCF network.

Adenoma↗
PubMed1993

Stereomicroscopic examination of surface morphology in colorectal epithelial tumors.

The mucosal surface structure of epithelial neoplasms in the large intestine was examined by a stereomicroscope, and the correlation between histologic and macroscopic features was studied. The surface structure of the colonic mucosa could be readily and clearly observed using the stereomicroscope after superficial staining, and neoplastic lesions were identified as well-defined foci of the unique structures that were conspicuously different from those in the normal mucosa. Five hundred two adenomas and 159 carcinomas were examined and divided into five types according to stereomicroscopic appearance: long ellipsoid (359 lesions), cerebriform (141 lesions), leaf-like (16 lesions), dense tiny pits (89 lesions), and devastated (56 lesions). In the first three types benign adenomas predominated in the majority of cases (94.7%, 72.3%, and 68.8%, respectively) and the variation in the surface features correlated well with the histologic types. In the latter two types the frequency of malignancy was strikingly high (49.4% and 92.9%, respectively), with the devastated mucosal appearance being highly indicative of invasive carcinoma. Macroscopically, exophytic polypoid configurations were frequently found in the first three types, whereas flat nonpolypoid configurations predominated in the cases with dense tiny pits. Our results indicate that there is a close relationship between the surface structure of epithelial neoplasms in the large intestine and their histologic features and growth patterns.

Adenoma↗
PubMed1993

Vimentin-positive gastric carcinomas with rhabdoid features. A clinicopathologic and immunohistochemical study.

We studied 71 patients with solid-type gastric adenocarcinoma selected from 5,437 surgically resected specimens during the period from 1975 to 1988; six had vimentin-positive adenocarcinomas, and five of these were advanced. One was at an early stage. All six tumors showed the same histologic features and had either a diffuse or alveolar arrangement, with tumor cells having either poor or no cohesiveness. Many tumor cells were round to polygonal, with eosinophilic or clear cytoplasm and large, eccentric vesicular nuclei, as seen in malignant rhabdoid tumors of the kidney. In all cases, the cytoplasm showed coexpression of vimentin and cytokeratin as revealed by double immunostaining. Four of the five cases with advanced carcinoma died of the disease 1 to 6 months after surgery. The cases with vimentin-positive tumors had significantly poorer prognoses than those with vimentin-negative tumors. We also studied adenocarcinomas of various histologic types randomly selected from our file (160 intestinal type and 69 diffuse type of Lauren) but failed to detect any vimentin positive ones. These results indicate that vimentin is expressed in some of the solid-type adenocarcinomas, which have a poor prognosis, and indicating that rhabdoid-like cells may be found in a variety of adenocarcinomas of the stomach.

Adenocarcinoma↗
PubMed1993

Inflammatory fibroid polyp of the stomach. A special reference to an immunohistochemical profile of 42 cases.

Forty two cases (46 lesions) of inflammatory fibroid polyp (IFP) of the stomach were reviewed histologically and studied immunohistochemically. The paraffin sections were stained with a panel of antibodies against alpha-smooth-muscle actin, HHF-35, desmin, vimentin, lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, KP1, Mac 387, S-100 protein, neuron-specific enolase, factor VIII RAg, and with Ulex europaeus agglutinin I. The lesions ranged in size from 0.3 to 3.5 cm with a mean of 1.2 cm. Forty (87.0%) IFPs occurred in the antrum, five in the gastric body, and one in the cardia. In all but two lesions, the mucosal layer was involved, and 20 (43.5%) lesions were entirely restricted to the mucosa. All 46 IFPs tested diffusely positive with vimentin. Positive reactions for alpha-smooth-muscle actin and HHF-35 were observed in 12 (26.1%) and 10 (21.7%) IFPs, respectively. Two lesions with alpha-smooth-muscle actin and one lesion with HHF-35 showed a diffuse staining. Seventeen (37.0%) lesions were focally positive for KP1, and seven (15.2%) IFPs were focally positive for Mac 387. All other antibodies and agglutinin were negative with the proliferating cells. The results of this study confirmed (a) the presence of myofibroblastic and histiocytic lines of differentiation in addition to the main fibroblastic features for the main cellular component in IFP, and (b) the heterogeneity of the immunoprofile of IFP.

Adult↗
PubMed1993

Intestinal pseudo-obstruction in patients with amyloidosis: clinicopathologic differences between chemical types of amyloid protein.

A clinicopathologic study was made of 16 patients with amyloidosis and with clinical signs of intestinal pseudo-obstruction. amyloid deposits in the small intestine were proved in all cases by endoscopic or intra-operative biopsies, and immunohistochemical study identified the chemical types of amyloid protein: amyloid A protein (AA) in 13 cases, light chain protein (AL) in two, and beta 2-microglobulin (AH) in one. Clinically, an acute self limiting obstructive condition was evident in 13 cases with AA, and 12 of them returned to normal bowel function after receiving total parenteral nutrition. Two cases with AL and one with AH presented chronic, intermittent, obstructive symptoms, and medical treatment, including total parenteral nutrition, was ineffective with no recovery of intestinal propulsion. Pathological examination of the necropsy specimens in seven cases showed considerable differences in the preferential sites of gastrointestinal deposits between the chemical types of amyloid; extensive infiltration and replacement of the muscularis propria by amyloid deposits throughout the gastrointestinal tract, especially the small intestine, were found in the AL and the AH cases, while amyloid deposits in the myenteric plexus without appreciable muscle infiltration were shown in the AA cases. These results show that intestinal pseudo-obstruction in patients with amyloidosis is caused by either myopathy or neuropathy, and that chemical types of amyloid may determine which of the two factors has the dominant affect on the bowel function.

Adult↗
PubMed1993

Minute nonpolypoid adenomas of the colon depicted with barium enema examination.

To evaluate the usefulness of barium enema examination for detection of small nonpolypoid adenomas, the barium enema study findings were reviewed in patients with flat or depressed adenomas of the colon 3-5 mm in diameter that had been initially found during colonoscopy and that had been diagnosed as adenomas at histologic analysis. Eleven of the 21 nonpolypoid adenomas were depicted on radiographs; they tended to be located on the left side of the colon. The 10 other lesions were not detected retrospectively on barium enema radiographs. The radiographic findings in the depicted lesions included smooth, round, radiolucent areas; in seven of these lesions, round or irregular barium flecks were also seen. The radiolucent areas were attributed either to slightly elevated growth of adenomas or to surrounding hyperplasia of nonneoplastic glands; the central barium fleck seemed to conform to depressed areas within adenomas. Barium enema examination can demonstrate nonpolypoid adenomas of the colon, even though colonoscopy seems superior to barium enema examination for detection of these lesions.

Adenoma↗
PubMed1993

Intestinal Behçet disease: serial changes at radiography.

To clarify the characteristic radiographic findings and serial radiographic changes in nonsurgical cases of intestinal Behçet disease (BD), seven patients were followed up for an average of 4 1/2 years (range, 8 months to 11 years 4 months). They underwent repeated examination with barium meal studies and double-contrast barium enema meal studies and double-contrast barium enema radiography. Initial radiography revealed one to three deep ulcers in the terminal ileum or ileocecal region in five patients. The ulcers healed while patients were treated with medical therapy but recurred during the follow-up period. In four of these five patients, follow-up radiography demonstrated various changes within each case: At each examination, an enlarged ulcer or a newly developed ulcer was often found in conjunction with a healed ulcer. In the other two patients, multiple shallow ulcers or innumerable aphthoid ulcers were seen throughout the entire colon, and these ulcers showed a good response to medical treatment. These results indicate that serial radiographic changes in patients with intestinal BD may mimic those in patients with Crohn disease, with findings in the terminal ileum and colon that wax and wane with medical treatment.

Adult↗
PubMed1993

Natural history of fundic gland polyposis without familial adenomatosis coli: follow-up observations in 31 patients.

PURPOSE: To clarify the natural history of fundic gland polyposis (FGP) without familial adenomatosis coli (FAC). MATERIALS AND METHODS: Thirty-one FGP patients without FAC (six men and 25 women) were followed up with radiography and endoscopy for 1-13 years (mean, 4.3 years). RESULTS: In eight of 11 patients who initially had a single polyp, the polyp disappeared, probably due to endoscopic forceps biopsy. Of 20 patients with multiple polyps, seven (one man and six women with a mean age of 40.6 years at initial diagnosis) had obvious changes in the number of polyps, including complete disappearance in three patients, a decrease in one, transient disappearance followed by recurrence in two, and an increase in one. These patients were younger and had a greater number of polyps at initial diagnosis than the remaining 16 patients without any remarkable change. CONCLUSION: FGP without FAC is characterized by spontaneous decrease or increase in the number of polyps, especially in middle-aged female patients with a large number of polyps.

Adenomatous Polyposis Coli↗
PubMed1993

Acupuncture and somatic nerve stimulation: mechanism underlying effects on cardiovascular and renal activities.

Acupuncture and acupuncture-like somatic nerve stimulation exert modulatory effects upon cardiovascular and renal activity under different physiological and pathophysiological conditions. It seems that acupuncture facilitates the physiological reflexes in response to changes in internal or external environment. Thus, acupuncture can lower high blood pressure in hypertensives, elevate low blood pressure in hypotensives, and promote urinary sodium excretion during hyperosmotic challenge, etc. Acupuncture effects are thought to be mediated by activation of the small myelinated fibres coming from muscle receptors. Preliminary studies show that different neurotransmitters and neuropeptides are involved in the effects of acupuncture.

Acupuncture Therapy↗
PubMed1993

[Detection of obscure fistulas complicated with Crohn's disease by indocyanine green].

When treating patients with Crohn's disease (CD), external or internal fistulas connected to the intestine were encountered, and these were often difficult to diagnose correctly. In order to diagnose such fine fistulas, we modified a method of using indocyanine green (ICG) administration to the gut lumen. The subjects of this study comprised nine patients with CD who had an obscure fistula which could not be demonstrated by barium study, fistulography, or by urological or gynecological examinations. If the administrated ICG was detected by various ways from an external fistula or from the neighboring organs, a fistulous connection was thought to be evident. Following oral administration in nine patients, colonic fistulas became evident in seven and by ICG enema in three patients, colonic fistulas became evident in all three. In addition, since the fistulous connection was ameliorated following nutritional therapy, it would appear that ICG administration is a useful marker of such therapy for this condition. ICG administration was therefore thought to be a useful method of detecting obscure fistulas connected to the intestine.

Adult↗
PubMed1993

Large intra-abdominal desmoid tumors in a patient with familial adenomatosis coli: their rapid growth detected by computerized tomography.

A case of familial adenomatosis coli with large intra-abdominal desmoid tumors is described. The patient initially complained of an abdominal mass, which was diagnosed as a desmoid tumor after surgical resection. Further examinations revealed numerous polyps of the colon which were histologically diagnosed as adenomas. Despite intensive medical therapy, the desmoid tumors rapidly increased in size and number, and resulted in abscess and cavity formation that involved the ileum. Although desmoid tumors are classically benign in nature, we consider these tumors to be a therapeutic problem in patients with familial adenomatosis coli.

Abdominal Neoplasms↗
PubMed1993

[The long-term follow-up study of Japanese patients with ulcerative colitis].

To elucidate the long-term outcome of the ulcerative colitis we analyzed 124 patients suffering for more than 10 years concerning the long-term prognosis, cumulative rate of colectomy, cumulative risk of cancer development and cumulative survival rate. Long-term prognosis were divided to three categories as good, fair and poor, according to present disease activities, social availability and subjective judgement. One hundred and twenty four patients were divided to 66 patients with good prognosis, 27 fair and 31 poor (2:1:1). The rate of patients having active disease at each year were followed-up annually for 10 years according to final three categories of the prognosis. The serial curve of annual rate of having active disease of the patients with poor prognosis was the highest, fair prognosis the second, good prognosis the lowest. The factors affecting the final prognosis were the period before initiation of proper treatment, the severity of the first attack or the elder age (> 40 year old) at the first attack. Twenty six patients were undergone colectomy in relation to ulcerative colitis. The cumulative colectomy rate was 16.5% at 10 years and 38.5% at 15 years after the onset. Malignant disease or severe dysplasia of the colon developed in 4 patients 10 to 14 years after the onset. Cumulative survival rate was equal to the expected survival curve during 16 years. The main causes of death were intracranial hemorrhage and colorectal malignant disease.

Adolescent↗
PubMed1992

Pathology and prognosis of gastric carcinoma. Findings in 10,000 patients who underwent primary gastrectomy.

BACKGROUND: Despite recent advances in diagnosis and treatment, gastric carcinoma remains a major cause of death in the world. METHODS: The clinicopathologic profile of 10,000 consecutive patients who underwent primary gastrectomy during 1962-1989 were reviewed and prognostic factors influencing survival in those with gastric carcinoma were analyzed in 7031 patients. RESULTS: Incidence of gastrectomy for carcinoma has increased steadily and the rate of early carcinoma exceeded that of advanced carcinoma in the recent period of 1985-1989. Five-year and 10-year survival rates were 46.1% and 35.2% in 3868 patients with advanced carcinoma, and 88.8% and 77.3% in 3163 patients with early carcinoma, respectively. In patients with advanced carcinoma, significantly poorer survival rates were noticed for patients older than 70 years of age, those who underwent total gastrectomy, tumors involving the entire stomach or greater than 10 cm in diameter, a macroscopic diffusely infiltrative pattern, adenosquamous histologic type, positive surgical resection margins, or lymph node metastasis. None of the above poor prognostic features were identified in patients with early gastric carcinoma group except for those older than 70 years of age. Although lymph node metastases were present in 10% of early gastric carcinomas, this feature did not impart a poor prognosis. Patients with advanced carcinoma grossly resembling an early carcinoma had an intermediate prognosis, suggesting the existence of a developmentally midstage lesion between early and advanced carcinoma. CONCLUSIONS: The study illustrates that the most important role for clinicians treating with gastric carcinoma should be early detection and aggressive surgery for resectable tumors, followed by detailed pathologic examination.

Adenocarcinoma↗