OBJECTIVETo determine the accuracy and clinical value of combining 64 multi-slice spiral computer tomography (MSCT) and serum amyloid A protein (SAA) in the preoperative staging of rectal cancer.

METHODSProspectively enrolled patients with rectal cancer from October 2007 to October 2008. The patients were randomly assigned into two groups: MSCT and SAA combined group: both MSCT and SAA combinative assessment were performed for preoperative evaluation; MSCT group: only MSCT was performed preoperatively for tumor staging. The accuracy of the preoperative T, N, M, and TNM staging and the concordance rate of predictive operative strategy were compared between the two groups.

RESULTSTotal of 225 cases with rectal cancer were enrolled in this study. There were 110 cases in MSCT and SAA combined group and 115 cases in MSCT group. The baseline characteristics was comparable between the two groups. For MSCT and SAA combined group, the accuracies of preoperative staging of T, N, M and TNM was 87.3%, 85.2%, 100% and 86.4%, respectively; and for MSCT group, the corresponding rates was 85.2%, 67.0%, 100% and 66.1%, respectively. Statistical differences was found in the accuracy of preoperative N and TNM staging between the two groups (P = 0.009 and 0.001, respectively). In addition, there was statistical difference in the accuracy of prediction to operative procedures between the two groups (94.7% vs. 81.7%, P = 0.003).

CONCLUSIONCombinative assessment of MSCT and SAA could improve the accuracy of preoperative staging, and thus provide higher predictive coincidence rate of operative procedures.