Related Experiment Video
Updated: Sep 2, 2026

Models of Bone Metastasis
Published on: September 4, 2012
Bone metaplasia in the urinary tract: a new radiological sign
E Garcia-Cuerpo1, F Lovaco, A Berenguer
1Department of Urology, Hospital Ramón y Cajal, Madrid, Spain.
Abstract:
We report 7 cases of bone tissue in the upper urinary tract. Routine excretory urography was suspicious for renal lithiasis. However, pathological evaluation of the kidney tissue revealed bone metaplasia in all 7 cases. Retrospective examination of the first 6 cases showed a typical radiological sign, consisting of a radiopaque eccentric halo surrounding an area of lesser radiological density that, in turn, connected with the urothelium. These findings permitted a correct preoperative diagnosis of bone metaplasia in case 7. Accurate preoperative differentiation of bone metaplasia (false calculi) and true renal lithiasis is important owing to the different treatments required.
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Cellular Adaptation IV: Dysplasia and Metaplasia

