Diagnostic Value of Endorectal Ultrasound in Preoperative Assessment of Lymph Node Involvement in Colorectal Cancer: a Meta-analysis

Background: Nodal invasion by colorectal cancer is a critical determinant in estimating patient survival and inchoosing appropriate preoperative treatment. The present meta-analysis was designed to evaluate the diagnosticvalue of endorectal ultrasound (EUS) in preoperative assessment of lymph node involvement in colorectal cancer.Materials and
Methods: We systematically searched PubMed, Web of Science, Embase, and China NationalKnowledge Infrastructure (CNKI) databases for relevant studies published on or before December 10th, 2014.The sensitivity, specificity, likelihood ratios, diagnostic odds ratio (DOR) and area under the summary receiveroperating characteristics curve (AUC) were assessed to estimate the diagnostic value of EUS. Subgroup analysisand meta-regression were performed to explore heterogeneity across studies.
Results: Thirty-three studiescovering 3,016 subjects were included. The pooled sensitivity and specificity were 0.69 (95%CI: 0.63-0.75) and0.77 (95%CI: 0.73-0.82), respectively. The positive and negative likelihood ratios were 3.09 (95%CI: 2.52-3.78)and 0.39 (95%CI: 0.32-0.48), respectively. The DOR was 7.84 (95%CI: 5.56-11.08), and AUC was 0.80 (95%CI:0.77-0.84).
Conclusions: This meta-analysis indicated that EUS has moderate diagnostic value in preoperativeassessment of lymph node involvement in colorectal cancer. Further refinements in technology and diagnosticcriteria are necessary to improve the diagnostic accuracy of EUS.