Solid masses arising in transplanted kidneys.

Renal transplantation is an established surgical option for patients with end-stage renal failure and leads to considerable improvement in the survival and quality of life of these patients. Imaging, particularly sonography, is often used to follow-up of renal transplant patients. CT and MRI are used to further assess abnormal sonographic findings. Uncommonly, these patients present with a mass in the allograft. In this review, we discuss the causes and imaging findings of solid masses that arise in or around the renal allograft.