Purpose Mucin expression is a common feature of most adenocarcinomas and features prominently in current attempts to improve diagnosis and therapy of pancreatic cancer and other adenocarcinomas. We investigated the expression of a number of mucin core proteins and associated O-linked glycans expressed in pancreatic adenocarcinoma (PA) – sialyl Tn (STn), Tn, T antigen, sialyl Lewis A (CA19-9), sialyl Lewis C (SLeC), Lewis X (LeX) and sialyl Lewis X (SLeX) – during the progression of pancreatic cancer from early stages to metastatic disease. Experimental Design Immunohistochemical analyses of mucin and associated glycan expression on primary tumor and liver metastatic tumor samples were performed with matched sets of tissues from 40 autopsy patients diagnosed with PA, 14 surgically resected tissue samples, and 8 normal pancreata. Results There were significant changes in mucin expression patterns throughout disease progression. MUC1 and MUC4 were differentially glycosylated as the disease progressed from early PanINs to metastatic disease. De novo expression of several mucins correlated with increased metastasis indicating a potentially more invasive phenotype, and we demonstrate the expression of MUC6 in acinar cells undergoing acinar to ductal metaplasia. A “cancer field-effect” that included changes in mucin protein expression and glycosylation in the adjacent normal pancreas was also seen. Conclusions There are significant alterations in mucin expression and post-translational processing during progression of pancreatic cancer from early lesions to metastasis. The results are presented in the context of how mucins influence the biology of tumor cells and their microenvironment during progression of pancreatic cancer.

Leiomyomas are common benign tumors of the esophagus representing 10% of all mesenchymal tumors of the gastrointestinal tract. Prominent numbers of eosinophils involving a leiomyoma have only rarely been described. They have never been described involving a solitary leiomyoma of the esophagus. We present an unusual case of a solitary esophageal leiomyoma with a prominent number of eosinophils and mast cells, review the previous literature regarding this topic and discuss possible causes of the eosinophil infiltrate.

<p>PDF file - 320K, Supplementary Figure 2. Representative immunohistochemical results for comparison of cancer fieldeffects in autopsy and resection tissue samples from the same patients. Two different autopsy patients who underwent surgical resection are presented. Serial sections stained for the antigens indicated are shown in the resection tissue samples alongside the autopsy samples of their primary tumors. 200x magnification.</p>

<div>Abstract<p><b>Purpose:</b> Mucin expression is a common feature of most adenocarcinomas and features prominently in current attempts to improve diagnosis and therapy for pancreatic cancer and other adenocarcinomas. We investigated the expression of a number of mucin core proteins and associated O-linked glycans expressed in pancreatic adenocarcinoma—sialyl Tn (STn), Tn, T antigen, sialyl Lewis A (CA19-9), sialyl Lewis C (SLeC), Lewis X (LeX), and sialyl LeX (SLeX)—during the progression of pancreatic cancer from early stages to metastatic disease.</p><p><b>Experimental Design:</b> Immunohistochemical analyses of mucin and associated glycan expression on primary tumor and liver metastatic tumor samples were conducted with matched sets of tissues from 40 autopsy patients diagnosed with pancreatic adenocarcinoma, 14 surgically resected tissue samples, and 8 normal pancreata.</p><p><b>Results:</b> There were significant changes in mucin expression patterns throughout disease progression. MUC1 and MUC4 were differentially glycosylated as the disease progressed from early pancreatic intraepithelial neoplasias to metastatic disease. <i>De novo</i> expression of several mucins correlated with increased metastasis indicating a potentially more invasive phenotype, and we show the expression of MUC6 in acinar cells undergoing acinar to ductal metaplasia. A “cancer field-effect” that included changes in mucin protein expression and glycosylation in the adjacent normal pancreas was also seen.</p><p><b>Conclusions:</b> There are significant alterations in mucin expression and posttranslational processing during progression of pancreatic cancer from early lesions to metastasis. The results are presented in the context of how mucins influence the biology of tumor cells and their microenvironment during progression of pancreatic cancer. <i>Clin Cancer Res; 19(8); 1981–93. ©2013 AACR</i>.</p></div>