Abstract:

Objective To determine the TN staging of rectal cancer by transrectal ultrasonography（TRUS） and magnetic resonance imaging（MRI），and to compare the diagnostic accuracy of preoperative TRUS with that of MRI in detection of locally advanced rectal cancer（LARC）. Methods A total of 159 patients with rectal cancer diagnosed in our hospital from May 2019 to December 2021 who had preoperatively undergone both TRUS and MRI were collected. With postoperative pathological staging as the gold standard，the accuracy of TRUS and MRI in TN staging of rectal cancer was retrospectively analyzed. The diagnostic value of TRUS and MRI for LARC was compared. Results The accuracy rate of TRUS and MRI for T staging of rectal cancer was 83.02% and 82.40%，respectively，consistent with postoperative pathological staging；the Kappa value was 0.73 and 0.72，respectively， with statistical significance（P < 0.05）. For the accuracy of T staging，the sensitivity of MRI for T4 stage lesions was significantly better than that of TRUS，with statistical significance（P < 0.05）. The accuracy，sensitivity and specificity of TRUS for N staging were 81.13%，79.73% and 82.35%；while those of MRI were 75.47%，90.54% and 63.35%，respectively. The sensitivity of MRI was better than that of TRUS，and the specificity of TRUS was higher than that of MRI，with statistical significance（P < 0.05）. The accuracy and specificity of TRUS in the diag⁃ nosis of LARC were higher than those of MRI，with statistical significance（P < 0.05）. Conclusions TRUS and MRI have better consistency in T and N staging and pathological staging of rectal cancer. MRI is superior to TRUS in detection of T4 lesions，whereas TRUS is better than MRI in differentiation of LARC，which has certain guidingsignificance for clinically formulating personalized treatment plans.

Key words:

locally advanced rectal cancer, transrectal ultrasonography, MRI, T staging, N staging