Epigenetic silencing of NDRG2 induces proliferation and invasion of CRC and may be associated with proximal CRC and advanced T stage. NDRG2 methylation might serve as novel biomarker of CRC.

Although colorectal cancer (CRC) is considered one of the most preventable cancers, no non-invasive, accurate diagnostic tool to screen CRC exists. We explored the potential of urine nuclear magnetic resonance (NMR) metabolomics as a diagnostic tool for early detection of CRC, focusing on advanced adenoma and stage 0 CRC. Urine metabolomics profiles from patients with colorectal neoplasia (CRN; 36 advanced adenomas and 56 CRCs at various stages, n = 92) and healthy controls (normal, n = 156) were analyzed by NMR spectroscopy. Healthy and CRN groups were statistically discriminated using orthogonal projections to latent structure discriminant analysis (opLs-DA). the class prediction model was validated by threefold cross-validation. The advanced adenoma and stage 0 CRC were grouped together as pre-invasive CRN. The OPLS-DA score plot showed statistically significant discrimination between pre-invasive CRN as well as advanced CRC and healthy controls with a Q2 value of 0.746. In the prediction validation study, the sensitivity and specificity for diagnosing pre-invasive CRN were 96.2% and 95%, respectively. The grades predicted by the OPLS-DA model showed that the areas under the curve were 0.823 for taurine, 0.783 for alanine, and 0.842 for 3-aminoisobutyrate. In multiple receiver operating characteristics curve analyses, taurine, alanine, and 3-aminoisobutyrate were good discriminators for CRC patients. NMR-based urine metabolomics profiles significantly and accurately discriminate patients with pre-invasive CRN as well as advanced CRC from healthy individuals. Urine-NMR metabolomics has potential as a screening tool for accurate diagnosis of pre-invasive CRN. Colorectal Cancer (CRC) is one of the most common causes of cancer-related deaths globally. The incidence of CRC is expected to exceed 2 million new cases by 2030, resulting in more than 1 million deaths. Rapid increases in CRC incidence and mortality have been described in many low/middle-income countries 1,2. CRC development is characterized by very slow progression from adenoma to carcinoma due to the accumulation of various genetic and epigenetic mutations over decades 3. A large proportion of CRC cases and deaths could be prevented by screening and early detection and removal of colorectal adenomas or early stage CRC 4,5. Therefore, the development of reliable and non-invasive screening tools for early stage CRC and precancerous lesions, such as adenoma, is indispensable. Colonoscopic screening and surveillance have a well-documented benefit in reducing the risk of CRC by direct removal of precancerous lesion and early detection of CRC 6,7. However, the use of colonoscopy as a screening tool is limited because it is an invasive and unpleasant procedure that necessitates bowel preparation and sedation. Instead, the fecal occult blood test (FOBT) has been commonly used in the clinic. An unacceptably wide range or the lack of sensitivity and specificity of the FOBT has hampered its clinical application in CRC diagnosis, especially for precancerous lesions...

BACKGROUND Self-expandable metallic stent (SEMS) is widely used for malignant colorectal obstruction. Recently, SEMS has been used for palliative option for colorectal obstruction caused by extracolonic malignancy (ECM). AIM To evaluate the efficacy of SEMS for colorectal obstruction caused by ECM, and to identify the factors associated with stent occlusion. METHODS Seventy-two patients who were treated with uncovered SEMS insertion for malignant colorectal obstructions caused by colorectal metastasis or peritoneal seeding of ECM at Samsung Medical Center between April 2012 to March 2016 were enrolled. We analyzed technical and clinical outcomes of stent insertion, the factors associated with stent occlusion and long term outcomes after stent insertion. RESULTS Technical success rate was determined as 90.3% with a clinical success rate of 87.7%. Stent occlusion developed in 28.1%, with a median duration of 51 d. Further, 81.3% with stent occlusion could be treated with secondary stent insertion. Clinical failure was observed to be related to the male sex ( P = 0.020) and right colon obstruction ( P = 0.017). Stent length ≤ 10 cm was found to be associated with stent occlusion ( P = 0.003). Median survival time after stent insertion was 4.7 mo and 40.4% were able to receive their oncological treatments after stent insertion without surgery. CONCLUSION Uncovered SEMS is effective for the treatment of colorectal obstruction caused by ECM, considering life expectancy of patients with ECM.

No abstract