Metastatic disease of the ureter: patterns of tumoral spread and radiologic findings.

The radiographic and sectional imaging features (ultrasound [US], computed tomography [CT], and magnetic resonance imaging [MRI]) of ureteral obstruction due to metastatic disease are reviewed. The radiologic findings depend on the pattern of the tumoral spread: hematogenous submucosal/mucosal metastasis, hematogenous adventitia metastases spreading along periureteral vessels, scirrhous metastatic spread along periureteral vessels, or metastatic spread into lymph nodes with perinodal desmoplastic reaction. Solitary or multiple extraluminal obstructions without substantial displacement of the ureter are characteristic. CT is the examination of choice for morphological analysis. Together with the patient's history and clinical data, a presumptive diagnosis of ureteral obstruction caused by metastatic disease can be made.