AUTHOR=Xie Li , Jiang Xiyi , Li Qian , Sun Zujun , Quan Wenqiang , Duan Yuping , Li Dong , Chen Tianhui TITLE=Diagnostic Value of Methylated Septin9 for Colorectal Cancer Detection JOURNAL=Frontiers in Oncology VOLUME=Volume 8 - 2018 YEAR=2018 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2018.00247 DOI=10.3389/fonc.2018.00247 ISSN=2234-943X ABSTRACT=Background: Methylated Septin9 (mSEPT9) has been suggested as a reliable biomarker in colorectal cancer (CRC) detection. We aimed to determine the diagnostic value of mSEPT9 for blood-based CRC detection in Chinese patients. Additionally, we compared the diagnostic efficacy of mSEPT9 to traditional screening method (FOBT) and two blood-based tumor biomarkers (CEA and Ca-199). Methods: Overall 248 subjects including 123 patients with CRC and 125 controls were included. Plasma and fecal samples were collected for CEA, Ca-199, mSEPT9 and FOBT tests. Sensitivity and specificity were calculated to evaluate the diagnostic efficacy of each method; receiver operating characteristic (ROC) curve was plotted for the assessment of diagnostic accuracy, and comparisons among FOBT, mSEPT9 and the combination were assessed through area under the ROC curve (AUC). Results: MSEPT9 achieved overall sensitivity and specificity of 61.8% [95% confidence interval (CI): 53.0-69.9%)] and 89.6% (83.0-93.8%), respectively, with an AUC value of 0.757 (95%CI: 0.701-0.807), superior to FOBT [sensitivity: 61.4% (50.9-70.9%); specificity: 70.3% (59.1-79.5%); AUC: 0.658 (0.578-0.723)], CEA [sensitivity: 35.0% (27.1-43.7%); specificity: 62.6% (53.8-70.7%); AUC: 0.485 (0.411-0.559)] and Ca-199 [sensitivity: 17.9% (12.1-25.6%); specificity: 55.7% (48.9-64.1%); AUC: 0.353 (0.283-0.423)]. The combination of mSEPT9 and FOBT further improved sensitivity and AUC value of 84.1% (75.1-90.3%) and 0.807 0.752-0.863), respectively, while specificity was declined, reaching 62.2% (50.8-72.4%). Conclusions: MSEPT9 demonstrated best diagnostic ability in CRC detection compared to FOBT, CEA and Ca-199. The combination of mSEPT9 and FOBT further improved diagnostic sensitivity especially for early stage disease, which may provide a new approach for future CRC screening, though further investigations are warranted.