Radiation enteritis

Acute radiation enteritis is almost inevitable in the curative treatment of malignant tumors of the abdomen and pelvic area. It is frequently a self-limiting disorder of intestinal function associated with reversible mucosal changes of the intestine. The prevalence of chronic radiation enteritis has been underestimated in most surgical series and the majority of patients with symptoms probably do not seek medical advice until a serious complication occurs. Although associated with specific histologic features, the mechanism of chronic radiation injury is poorly understood. The prevalence, pathogenesis, diagnosis and approaches to the treatment and prevention of acute and chronic radiation enteritis are discussed herein. Recent investigative techniques should lead to a better understanding of the physiopathologic characteristics of radiation enteritis and, thereby, provide a more rational basis for treatment which, at the present time, is unsatisfactory. Attempts to reduce the prevalence of radiation enteritis should be directed toward careful patient selection for radiation treatment of the pelvis and to minimize injury to the small intestine, by reducing the volume of small intestine in the radiation area and providing more individualized dosimetry.     

CDX2 expression is progressively decreased in human gastric intestinal metaplasia, dysplasia and cancer.

Intestinal metaplasia is a key event in multistep gastric carcinogenesis. CDX2, a master regulator of intestinal phenotype, was shown to play a tumor-suppressive role in colon cancer. However, it was reported to be expressed in nearly all gastric intestinal metaplasia and many gastric cancers. As CDX2 is differentially expressed in normal stomach and intestine, we sought to relate the CDX2 expression to gastrointestinal differentiation along gastric carcinogenesis. The expression of CDX2 protein in gastric intestinal metaplasia, dysplasia and cancer was examined and related to their gastrointestinal differentiation. CDX2 expression was significantly decreased in incomplete intestinal metaplasia, which expresses both gastric mucins (MUC5AC and MUC6) and intestinal mucin (MUC2), compared with complete intestinal metaplasia, which expresses intestinal mucin (MUC2) only. Although incomplete intestinal metaplasia morphologically resembles colon, its CDX2 expression was apparently lower than that in the normal colon. Moreover, CDX2 expression was progressively reduced in gastric dysplasia and cancer. The CDX2 expression in gastric cancer was also inversely correlated with the expression of gastric mucins. As incomplete intestinal metaplasia is associated with higher risk of gastric cancer, its lower CDX2 expression compared with that in complete intestinal metaplasia and normal colon epithelium resolved the current contradiction between the tumor-suppressive role of CDX2 in the colon and the high prevalence of CDX2 in intestinal metaplasia. Further decrease of CDX2 expression in gastric dysplasia and cancer suggests that CDX2 plays a similar anticarcinogenic role in intestinal metaplasia as it does in colon. Intestinal metaplasia or dysplasia with low expression of CDX2 may serve as predictive markers for gastric cancer.     

A solid-phase blocking ELISA for detection of antibodies to Nipah virus

A monoclonal antibody (MAb) based solid-phase blocking ELISA was developed for detection of antibodies to Nipah virus. The ELISA was designed to detect remaining antigens on the plate with anti-Nipah MAb conjugate after the reaction with sample serum, and enabled simple procedure, detection of neutralizing antibody to Nipah virus, and application of samples from different animal species. Forty of 200 swine reference sera examined were positive by the ELISA, of which thirty seven were found positive by serum neutralization test. Sera from a total of 131 fruit bats captured in Malaysia were also tested and all found negative by the both tests. It is considered that the solid-phase blocking ELISA can be used as a screening test for Nipah virus infection followed by the serum neutralization test as confirmatory test.     

Esophageal bezoar due to karaya gum granules used as a laxative

Esophageal obstruction from soluble fiber laxatives, such as karaya gum, has been rarely reported in the literature. However, as such preparations are widely commercially available, it is important for gastroenterologists to be aware of their potential to form a bezoar in the esophagus due to swelling on contact with liquid. This report highlights such a case and discusses its challenging management.     

Androgen receptor in salivary gland carcinoma: A review of an old marker as a possible new target

The role of the androgen receptor (AR) as an immunomarker for diagnosis of salivary gland duct carcinoma (SDC) is well known. Other non‐squamous cell head and neck cancers (NSCC‐HN), including a small subset of salivary gland cancers (SGCs), can also express AR. With the increase in effective and powerful new generation of anti‐androgen agents and drugs administered orally, more targetable AR‐driven NSCC‐HN, such as subsets of SGCs, should be investigated for possible expression of AR. In this review, we focus on SGC subtypes, which could express AR and describe the main androgen deprivation therapy (ADT) strategies.     

Expression of proteins associated with hypoxia and Wnt pathway activation is of prognostic significance in hepatocellular carcinoma

In the development and progression of hepatocellular carcinoma, tumor hypoxia plays an important role, as does activation of the Wnt pathway. The aim of this study was to characterize the expression and interrelationship between hypoxia and Wnt-pathway-associated proteins as prognostic factors for hepatocellular carcinoma. Expression of HIF-1α, CA-IX, E-cadherin, β-catenin, and Ki-67 was assessed by immunohistochemistry in 179 primary hepatocellular carcinoma cases. Univariate and multivariate analyses were performed to assess the relationship between the clinicopathological factors, protein expression, overall survival (OS), and recurrence-free survival (RFS). By univariate analysis, tumor stage, size, satellitosis, and vascular invasion were confirmed as prognostic factors for worse OS and RFS. High expression of HIF-1α, CA-IX, β-catenin, Ki-67, and E-cadherin was observed in 60, 15, 64, 8, and 64 % of tumors, respectively, and this was significantly associated with poor OS. CA-IX, HIF-1α, and E-cadherin were independent predictors of poor prognosis. We stratified 169 patients into four groups according to the expression level of hypoxia and Wnt pathway markers. The group with high expression of both hypoxia and Wnt-pathway-associated proteins showed worst OS. The poor survival of this group was also significant in patients with early stage disease and tumor size of less than 5 cm (p?<?0.05). We identified a subgroup of hepatocellular carcinoma patients with high expression of both hypoxia and Wnt pathway proteins and found this predictive of poor survival. The therapeutic options for this group might need to be revisited.