Diagnostic accuracy of computed tomography for colon cancer staging: A systematic review

Background. Computed Tomography (CT) is a frequently used staging modality for colon cancer patients in clinical practice. Our aim was to systemically review the available literature on diagnostic accuracy of CT for TNM staging of colon cancer. Methods. A systematic review of literature was performed. PubMed was searched using MeSH terms with the following search terms: "Tomography, X-Ray Computed" or "Tomography, Spiral Computed" and Colonic Neoplasms. Studies on rectal cancer and studies without separate analyses for the colon were excluded. We identified 779 publications, of which 11 were included for review. Overall and sample-size-weight sensitivity, specificity, accuracy, true-positive, truenegative, false-positive, false-negative, positive and negative predictive values were calculated for T, N and M stages. Results. In the 11 studies, a total of 753 patients with 759 colon cancers underwent CT for staging. Sample-size-weighted sensitivity, specificity and accuracy for T-staging was 77%, 3% and 67%, respectively; for N-staging 76%, 55% and 69%, respectively; and for M-staging 85%, 98% and 95%, respectively. Additional clinical findings were reported in 59/372 (16%) patients, with 12 having a malignant and 47 a benign origin. Conclusions. While accuracy of CT for TN-staging of colon cancer is only reasonable, the real value of CT is its high accuracy to detect distant metastases.