CT Evaluation of the Findings of Nutcracker Syndrome in Patients with Bladder Cancer after Radical Cystectomy and Ileal Neobladder Formation: A Correlation with Hematuria

PURPOSE: Patients with bladder cancer may show hematuria after radical cystectomy with ileal neobladder formation, causing anxiety regarding tumor recurrence. Here, we aim to show that the nutcracker syndrome (NCS) can be a cause of hematuria post-operation, and is a common, rather than a rare syndrome. MATERIALS AND METHODS: A retrospective review of contrast-enhanced abdominopelvic CT (CE-APCT) and urine analysis (UA) findings of 255 patients with bladder cancer who underwent radical cystectomy and ileal neobladder formation between 2011 and 2016 was performed. In the CE-APCT review, the left renal vein flow patterns were evaluated to determine the presence of NCS findings. In the UA review, patients were classified according to the percentage of UA tests with positive hematuria among the total number of UA tests. RESULTS: CT findings of NCS were present in 31.9% of the 135 patients. In the positive hematuria group, there were 26% more patients with NCS findings than those without. CONCLUSION: NCS findings are prevalent even for bladder cancer patients after surgery, and there is a strong correlation between NCS findings and hematuria. Furthermore, the prevalence of NCS findings is much higher than urinary tract recurrence after the surgery.