Yield of urinary tract cancer diagnosis with repeat CT urography in patients with hematuria.

OBJECTIVE. The purpose of this study was to evaluate the yield of repeat CT urography (CTU) in detecting urinary tract malignancies in patients with hematuria. MATERIALS AND METHODS. A review of 5525 patients who underwent CTU between 2000 and 2011 revealed 751 (13.6%) patients who underwent repeat CTU. We excluded 127 patients with more than 3 years between examinations, 409 with nonhematuria indications, and 13 with less than 1 year of follow-up from a negative repeat examination. An additional 54 patients with malignancy diagnosed on the initial evaluation were excluded, leaving 148 patients in the study cohort (77 men and 71 women; mean age, 57 years). Patients were categorized on the basis of the presence or absence of findings suspicious for malignancy on initial CTU reports. Repeat CTU reports were correlated with cystoscopy, pathology, and clinical follow-up to determine the incidence of malignancy. Examinations negative for malignancy were confirmed with at least 1 year of clinical follow-up. CTU examinations of patients diagnosed with malignancy on repeat examination were reviewed by two radiologists in consensus. RESULTS. Initial CTU showed no findings suspicious for malignancy in 103 (70%) of 148 patients; of these, none had malignancy identified on repeat CTU. Among 45 (30%) patients with suspicious initial CTU findings, four malignancies were identified on repeat CTU (8.9%). Three were incidental to the initial suspicious finding; in retrospect, two were present on the initial CTU examination. CONCLUSION. In patients with hematuria, repeat CTU within 3 years is unlikely to show a urinary tract malignancy. These results support currently published guidelines.