Preoperative staging by multidetector-row computed tomography in patients with rectal carcinoma

Background: Multidetector-row computed tomography (MDCT, or multi-slice CT) has been introduced in 2000. So far, there has been no published study on this modality in patients with rectal carcinoma. Methods: Twenty patients with rectal carcinoma were preoperatively examined by MDCT and conventional CT (CCT). Diagnostic accuracies of both modalities were compared regarding the evaluation of depth of tumor invasion (Tis/T1/T2, T3, T4) and lymph node metastasis based on the pathologic findings. Results: Although CCT detected a tumor in 13 (65%) of 20 patients, MDCT revealed a tumor in all 20 patients (P = 0.004). Regarding depth of tumor invasion, the concordance rate was significantly higher for MDCT (20/20: 100%) than for CCT (12 of 20: 60%; P = 0.002). Regarding lymph node metastasis, the overall accuracy was 70.0% in CCT, and also 70.0% in MDCT. Conclusions: MDCT was superior to CCT in the evaluation of depth of tumor invasion, but was equal to CCT in the evaluation of lymph node metastasis.