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1.
Radical lymph node dissection for cancer of the thoracic esophagus.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE: The authors documented the localization and frequency of lymphatic spread in squamous cell carcinoma of the thoracic esophagus and evaluated the influence of radical systematic lymph node dissection on patient survival. SUMMARY BACKGROUND DATA: From accumulated surgical experience, it was suggested that some of the patients with lymph nodal involvement from cancer could be cured by its clearance. However, it is only recently that cancer of the esophagus has been evaluated in terms of analyzing lymphatic spread and results of lymphadenectomy. METHODS: Among 1298 patients admitted to the Toranomon Hospital between 1973 and 1993, 913 (70.3%) had resections, including curative and palliative procedures. For this study, 717 patients with TNM RO (resection with no residual tumor at operation in TNM classification) were analyzed. Survival was compared between groups of patients with less extensive thoracoabdominal (two-field) dissections and extensive collothoracoabdominal (three-field) dissections. RESULTS: Comparative study revealed that 5-year survival rate for TNM RO patients after free-field dissection (55.0%) was significantly better (log rank test, p = 0.0013) than the rate after two-field dissection (38.3%). The results were particularly significant in subgroups with stage III and IV (because of nodal factor). Overall 5-year survival rate after all resections was 42.4%. CONCLUSIONS: The role of radical lymph node dissection in cancer of the thoracic esophagus evaluated. Long-term survival was compared between two groups with two- and three-field dissection. It was concluded that survival rate was significantly better in patients with extensive three-field dissection.  相似文献   
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Surgical specimens from 19 patients with invasive colorectal cancers and 12 specimens of normal mucosa from the same patients were examined immunohistochemically for the production of the immunoreactive (IR-) transforming growth factor (TGF)-alpha and IR-epidermal growth factor (EGF) with an anti-TGF-alpha monoclonal antibody (MAb) OAL-MTG01 and anti-EGF MAb KEM-10. Immunoreactive TGF-alpha was detected in 16 (84.2%) of 19 colorectal cancers. In contrast, there was no IR-TGF-alpha in the gland cells of normal mucosa. Immunoreactive EGF was detected in 7 (36.8%) of 19 colorectal cancers and 1 (8.3%) of 12 cases of normal mucosa. The production of both IR-TGF-alpha and IR-EGF in colorectal cancer did not differ by histologic type and Dukes' stage. Immunoreactive TGF-alpha was detected at significantly higher incidence than IR-EGF in colorectal cancer. These results indicate that IR-TGF-alpha should prove valuable as a possible tumor marker in colorectal cancers, and it may be very useful in understanding the biology of colorectal cancer.  相似文献   
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Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C50 chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.  相似文献   
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Interleukin (IL)-8 is a multifunctional cytokine that can stimulate the division of endothelial cells. We examined the expression of IL-8 mRNA using Northern blot analysis and in situ mRNA hybridization (ISH) and protein production using enzyme-linked immunosorbent assay and immunohistochemistry in 8 human gastric carcinoma cell lines and 39 gastric carcinomas and corresponding normal mucosa (34 surgical specimens and 5 biopsy specimens). Of the 8 human gastric carcinoma cell lines, 6 expressed 1.8-kb IL-8 mRNA and secreted various levels of IL-8 protein. The expression of IL-8 by TMK-1 cells was induced by exposure to IL-1 alpha, epidermal growth factor, and transforming growth factor-alpha, shown previously to be autocrine growth stimulators for human gastric carcinoma cells. In tumor tissues, most of the tumors (28 of 34 surgical specimens and 4 of 5 biopsy specimens) expressed IL-8 at higher levels than the corresponding normal mucosa. ISH and immunohistochemical analyses revealed that IL-8 mRNA and protein were localized in the cytoplasm of tumor cells. The number of blood vessels in the gastric carcinomas was determined by using antibodies against CD34. The level of IL-8 mRNA in the neoplasms strongly correlated with vascularization (Spearman correlation, r = 0.812; P = 0.001). The data suggest that IL-8 produced by tumor cells may regulate neovascularization and, hence, the growth and spread of human gastric carcinoma.  相似文献   
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Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, is a secreted protein which may play a pivotal role in tumor-associated microvascular angiogenesis and hyperpermeability. The expression of mRNA for VEGF was examined in eight gastric carcinoma cell lines and 30 gastric carcinoma tissues as well as corresponding normal mucosa. All the cell lines expressed VEGF mRNA at various levels that correlated well with the amounts of VEGF secreted into the condition medium. The expression of VEGF mRNA by TMK-1 cells was increased by the treatment of epidermal growth factor (EGF) or interleukin-1α (IL-1α), whereas it was decreased by the treatment of interferon-β (IFN-β). In gastric carcinoma tissues, the level of VEGF mRNA in primary tumors was higher than that in the corresponding normal mucosas in six (46%) of 13 well-differentiated adenocarcinomas and in two (12%) of 17 poorly differentiated adenocarcinomas, respectively. Vessel counts in well-differentiated adenocarcinomas had a tendency to be higher than those in poorly differentiated adenocarcinomas. In well-differentiated adenocarcinomas, the levels of VEGF mRNA expression tended to be higher in carcinomas of advanced stage than in early stage carcinomas. Both in situ mRNA hybridization and immunohistochemistry demonstrated the presence of VEGF expression within the tumor cells. These results suggest that VEGF may confer angiogenesis and progression of human gastric carcinomas, especially of the well-differentiated type.  相似文献   
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We studied the expression of cell cycle regulators and growth factor-receptor systems in gastric carcinoma in young adults and tried to clarify the specific alterations associated with H. pylori. We studied 33 young patients (18-29 years old, mean age 26.4) with gastric carcinoma. The patients were classified into two groups according to the degree of atrophic gastritis. Then we examined the expression of p53, cripto, cyclin-E, c-met, c-erbB2 and TGF-alpha immunohistochemically and compared the results between the two groups. The results were compared with 66 sex-, tumor histology-, and depth-matched elder controls (36-86 years old, mean age 64.0). H. pylori was judged by Giemsa staining. Seventeen patients had atrophic changes in the corpus (Group A), while 16 showed superficial gastritis or normal mucosa (Group S). All 17 patients of Group A showed H. pylori infection, while the 3 of the 16 members of Group S did not have H. pylori. p53 overexpression was observed more frequently in Group S (88%) than in Group A (41%, p<0.05). In the 3 patients without H. pylori infection, all carcinoma specimens showed p53 overexpression. Overexpression of cyclin-E was detected in 4 patients from Group S. On the other hand, cripto was observed more frequently in Group A than in Group S. No obvious differences were observed in c-erbB2, TGF-alpha and c-met expression. Overall, p53 overexpression was detected more frequently in younger than in older patients, whereas cripto expression was less detected. These results suggest that p53 and cyclin-E may act in an H. pylori-independent or -adjunctive manner for gastric carcinogenesis. Cripto expression might be correlated tightly with H. pylori infection.  相似文献   
8.
Restriction fragment length polymorphisms of the vitamin D receptor gene have recently been reported to be associated with changes in bone mineral density. Alterations in systemic calcium balance and Ca-regulating hormones such as 1,25(OH)2 vitamin D3 and parathyroid hormone have been demonstrated in essential hypertension. We investigated the relationship between polymorphisms of the vitamin D receptor gene and systemic Ca metabolism in patients with essential hypertension and in normotensives. We compared 147 subjects with essential hypertension and 100 normotensive control subjects. The genotype distribution and derived allele frequencies for the vitamin D receptor gene were similar in the two groups (genotype bb/Bb/BB and allele B/b: 60.1/32.6/7.2 and 0.24/0.76 in hypertensives vs. 56.0/36.0/8.0 and 0.26/0.74 in normotensive subjects). Serum concentrations of total Ca in the bb, Bb, and BB groups were, respectively, 4.5+/-0.3 vs. 4.5+/-0.4 vs. 4.4+/-0.5 mmol/l in normotensives and 4.6+/-0.3 vs. 4.6+/-0.4 vs. 4.4+/-0.5 mmol/l in hypertensives. Ionized Ca levels were 1.17+/-0.04 vs. 1.16+/-0.04 vs. 1.15+/-0.04 mmol/l in normotensives and 1.16+/-0.04 vs. 1.16+/-0.04 vs. 1.14+/-0.05 mmol/l in hypertensives, respectively. These results indicate that the BB genotype of the vitamin D receptor gene is associated with lower serum Ca levels but is not a useful predictive marker for the development of essential hypertension in Japanese subjects.  相似文献   
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Fifty-eight surgically resected cases of intrahepatic cholangiocarcinoma (ICC) were examined grossly and microscopically. We microscopically categorized the ICC into two groups, "scirrhous-type" ICC (SICC) and "nonscirrhous-type" ICC (NSICC), according to the degree of the stromal desmoplasia in the tumor. We next assessed the histologic characteristics including proliferative activities and prognoses. Additionally, the prognostic factors of ICC were examined by univariate and multivariate analyses. Histologically, the incidences of lymphatic permeation and perineural invasion in SICC (85.7% and 100.0%, respectively) were significantly higher than those in NSICC (47.7% and 45.6%, respectively). The mean MIB-1 labeling index of SICC (mean+/-standard deviation, 29.9%+/-14.3%) was significantly higher than that of NSICC (mean+/-standard deviation, 19.1%+/-14.3%). Additionally, the 1- and 3-year survival rates of the SICC were 64.3% and 22.0%, respectively, and those of NSICC were 72.8% and 55.8%, respectively. The survival rate of SICC was significantly lower than that of NSICC. Overall, lymphatic permeation, intrahepatic metastasis, and lymph node metastasis were all considered to be independent prognostic factors for a worse prognosis based on the multivariate analyses, whereas our new category based on stromal desmoplasia or other variables were not. Our study thus indicates that lymphatic permeation, perineural invasion, and a higher proliferative activity of tumor cells carry a poorer prognosis in SICCs than in NSICCs. Although the overall independent prognostic factors were lymphatic permeation, intrahepatic permeation, and lymph node metastasis based on a multivariate analysis, a detailed histologic examination related to the stromal desmoplasia in the tumor is also considered to be useful for evaluating the biologic behavior of the ICC.  相似文献   
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