Cystic Renal Masses: Old and New Paradigms

Abstract

Cystic renal masses describe a spectrum of lesions with benign and/or malignant features. Cystic renal masses are most often identified incidentally with the Bosniak classification system stratifying their malignant potential. Solid enhancing components most often represent clear cell renal cell carcinoma yet display an indolent natural history relative to pure solid renal masses. This has led to an increased adoption of active surveillance as a management strategy in those who are poor surgical candidates. This article provides a contemporary overview of historical and emerging clinical paradigms in the diagnosis and management of this distinct clinical entity.

Keywords: Active surveillance; Bosniak; Complex renal cysts; Cystic renal masses; Renal biopsy; Renal cyst; Small renal mass; Surgery.