Objective The purpose of the study was to test the hypothesis that cardiac mucosa, carditis, and specialized intestinal metaplasia at an endoscopically normal-appearing cardia are manifestations of gastroesophageal reflux disease. Summary Background Data In the absence of esophageal mucosal injury, the diagnosis of gastroesophageal reflux disease currently rests on 24-hour pH monitoring. Histologic examination of the esophagus is not useful. The recent identification of specialized intestinal metaplasia at the cardia, along with the observation that it occurs in inflamed cardiac mucosa, led the authors to focus on the type and condition of the mucosa at the gastroesophageal junction and its relation to gastroesophageal reflux disease. Methods Three hundred thirty-four consecutive patients with symptoms of foregut disease, no evidence of columnar-lined esophagus, and no history of gastric or esophageal surgery were evaluated by 1) endoscopic biopsies above, at, and below the gastroesophageal junction; 2) esophageal motility; and 3) 24-hour esophageal pH monitoring. The patients were divided into groups depending on the histologic presence of cardiac epithelium with and without inflammation or associated intestinal metaplasia. Markers of gastroesophageal reflux disease were compared between groups (i.e., lower esophageal sphincter characteristics, esophageal acid exposure, the presence of endoscopic erosive esophagitis, and hiatal hernia). Results When cardiac epithelium was found, it was inflamed in 96% of the patients. The presence of cardiac epithelium and carditis was associated with deterioration of lower esophageal sphincter characteristics and increased esophageal acid exposure. Esophagitis occurred more commonly in patients with carditis whose sphincter, on manometry, was structurally defective. Specialized intestinal metaplasia at the cardia was only seen in inflamed cardiac mucosa, and its prevalence increased both with increasing acid exposure and with the presence of esophagitis. Conclusion The findings of cardiac mucosa, carditis, and intestinal metaplasia in an endoscopically normal-appearing gastroesophageal junction are histologic indicators of gastroesophageal reflux disease. These findings may be among the earliest signs of gastroesophageal reflux and contribute to the authors understanding of the pathophysiology of the disease process.
2563 Background: The prognosis of colon cancers with hematogenous spread remains poor at 12–20 months. We report the use of a dendritic cell based immunotherapy to improve patient survival, especially with cell culture conditions mimicking infection. Methods: After isolating monocytes from the blood of 39 patients with metastasized colon cancer, dendritic cells were generated ex vivo in the presence of recombinant cytokines (IL-4; GM-CSF) and autologous serum. The DC loaded with tumor cell lysate were administered to the patients intradermally. Culture conditions were tested for upregulation of costimulatory molecules, downregulation of IL-10 and upregulation of IL-12 secretion by ELISPOT and fluorescence cytometry. Results: DC vaccination induced a clinical response in 9 (23%) patients with a median overall survival after onset of DC-therapy of 12 months (11–44 months for responders and 1–20 months for non-responders) and 23 months after diagnosis of metastases (16–63 months for responders and 1–23 months for non-responders). These data show that a dendritic cell based immunotherapy may prolong the patients overall survival. However, complete remissions are rare. This can be due to weak stimulation of CTL response due to insufficient antigen presentation, lack of costimulatory molecules as well as secretion of IL-10 rather than IL-12 by the DC’s. Here we could show that Toll-like receptors (TLR) ligands like Poly-I:C or lipopeptides as so called danger signals in combination with interferons can induce an upregulation of costimulatory molecules accompanied by inhibition of IL-10 and induction of IL-12 secretion in vitro. By using these culture conditions we induced a clinical complete remission of liver metastases after failure of standard therapy in one patient (overall survival after onset of DC-therapy 13 months, after diagnosis 24 months). Conclusions: According to Matzinger’s hypothesis an effective immune response occurs only by responding to a danger signal associated with infection or stress. Thus, cell culture condition should be used with TLR ligands mimicking a bacterial or viral infection. In general, a dendritic cell based immunotherapy can be successful in advanced stages of colon cancer patients. [Table: see text]
