The sensitivity and specificity of MDCT for depiction and localization of urothelial carcinoma (UC) was determined retrospectively. Axial and coronal four-row MDCT of the urinary tract (unenhanced, contrast-enhanced nephrographic, CT urography) was independently reviewed for UC by a radiologist (R1) and a urologist (R2), without other patient information, in 27 patients (22 male, five female; age, 72 +/- 11 years) with previous UC and/or painless macroscopic haematuria. Urinary tract segments included bladder, right and left upper, middle, and lower caliceal groups, renal pelvis, uretero-pelvic junction, upper, middle, and lower ureter. MDCT findings were corroborated by surgery, other invasive procedures, and 1-year follow-up, including MDCT, intravenous urography, and cystoscopy. Receiver-operating characteristic analysis was undertaken and the the area under the curve (AUC) calculated. Eighteen of 27 patients had evidence of UC (pTa, n = 3; pT1-pT3, n = 15; TNM 2002). Tumor was correctly located by both R1 and R2 in 17 patients (sensitivity, 94%; 95% confidence interval, 84-100%) and ruled out in seven (specificity, 78%; 95% confidence interval, 51-100%), with complete agreement. Each detected ten of 11 upper urinary tracts affected by UC. For 35 urinary tract segments with UC and 308 without, the AUC was 0.910 +/- 0.035 (R1) and 0.74 +/- 0.055 (R2), z = 2.4772, Bonferroni-corrected P = 0.022. MDCT depicts urinary tracts affected by UC with high sensitivity and substantial agreement between readers with different training.