The combination of transrectal ultrasonography and serum CEA in preoperative staging of rectal carcinoma

Abstract

Objective To evaluate the diagnostic accuracy of the combination of endorectal ultrasonography and serum CEA in preoperative diagnosis of rectal wall invasion (T staging) and nodal involvement (N staging) of rectal carcinoma.Methods We retrospectively analyzed clinical records of 310 patients with rectal carcinoma who underwent endorectal ultrasonography and serum CEA evaluation in Shanxi Province Tumor hospital from January 2007 to January 2010.The positive standard of CEA is more than 5 μg/L.The endorectal ultrasonography staging with postoperative pathological staging,and calculated the overall accuracy of T staging and N staging based on TRUS alone or on TRUS combined with serum CEA level were compared.Results The difference in serum CEA level was statistically significant from T1 to T4 (P ＜ 0.05).The accuracy rate of preoperative T staging of rectal carcinoma by TRUS alone was 71％ (219/310) and was 82 ％ (254/310) with TRUS combined with serum CEA level,showing significant statistical difference (x2 =10.92,P ＜ 0.01).The accuracy rate of preoperative N staging of rectal carcinoma was 69 ％ (211/308)with TRUS alone and was 77 ％ (238/308) with TRUS combined with serum CEA level,the difference of which was statistically significant (x2 =5.00,P ＜ 0.05).Conclusion Serum CEA level increases with an increasing pathological stage of rectal cancer.The combination of TRUS and serum CEA improves the accuracy of preoperative staging of rectal cancer. Key words: Rectal neoplasm; Endosonography; Neoplasm staging; Carcinoembryonic antigen