Ureteral involvement by a tumor is common, and both partial and complete obstructions can result in symptoms that are distressing and debilitating, especially in cancer patients for whom the resection of the primary tumor is not considered an option. Maintaining ureteric patency in these patients is a challenge. In addition, in cases where a patient has undergone nephroureterectomy due to primary transitional cell cancer, it becomes necessary to decompress the urinary tract to preserve the contralateral kidney from irreversible damage. This is possibly due to ureteral stenting, both retrograde and anterograde, and percutaneous nephrostomy (PCN). Since imaging plays an important role in the routine monitoring of stents, their more and more increasing use requires radiologists to be familiar with these devices, their correct position, their potential complications, and their consequences. The aim of this review is to offer a comprehensive review of the imaging features of some urinary stents and to show the complications encountered in cancer patients as a direct consequence of an invasive diagnostic or therapeutic procedure. Specifically, we focus on ureteral stents and PCN.