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Purpose: Gallbladder carcinoma is an aggressive type of cancer that is difficult to cure by conventional procedures. There thus is a need to identify novel molecular markers for the assessment of prognosis and as potential therapeutic targets. This retrospective study was designed to investigate the prognostic significance of epithelial cell adhesion molecule (Ep-CAM) overexpression in human gallbladder carcinoma.Experimental Design: Ep-CAM expression was examined immunohistochemically on paraffin-embedded tissue specimens from 99 patients who underwent surgical treatment for gallbladder carcinoma in the period between August 1988 and May 1999.Results: Ep-CAM overexpression was found in 63 (63.6%) of the tumor samples. Kaplan-Meier curves showed that Ep-CAM overexpression was significantly related to decreased overall survival (P < 0.01). Overall survival gradually worsened with increasing Ep-CAM scores. Notably, in the subgroup of pT1 tumors (n ‫؍‬ 17), patients without Ep-CAM overexpression had a 5-year overall survival rate of 100% compared with 38% (P ‫؍‬ 0.01) for patients with Ep-CAM-overexpressing tumors. By univariate analysis, no correlation was found with conventional clinicopathological parameters. Multivariate analysis, including Ep-CAM expression, pT stage, tumor grade, and resection margin involvement, showed that Ep-CAM overexpression was an independent prognostic marker in gallbladder carcinoma (P ‫؍‬ 0.03; relative risk, 1.8).Conclusions: These results demonstrate for the first time that Ep-CAM overexpression is an independent prognostic marker in gallbladder carcinoma and that its prognostic impact should be validated prospectively. Furthermore, the Ep-CAM antigen represents an attractive target for specific therapies with monoclonal antibodies or specific vaccines in patients with Ep-CAM-overexpressing gallbladder carcinoma.

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Thermal degradation of poly(dimethylsilylene) homopolymer (PDMS) and poly(tetramethyldisilylene‐co‐styrene) copolymer (PTMDSS) was investigated by pyrolysis‐gas chromatography and thermogravimetry (TG). PDMS decomposes by depolymerization, producing linear and cyclic oligomeric products, whereas PTMDSS decomposes by random degradation along the chain resulting in each monomeric product and various other combination products. The homopolymer was found to be much less stable than the copolymer. The decomposition mechanisms leading to the formation of various products are shown. The kinetic parameters of thermal degradation were evaluated by different integral methods using TG data. The activation energies of decomposition (E) for the homopolymer and the copolymer are found to be 122 and 181 kJ/mol, respectively, and the corresponding values of order of reaction are 1 and 1.5. The observed difference in the thermal stability and the values of the kinetic parameters for decomposition of these polymers are explained in relation with the mechanism of decomposition. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006