Cystic Renal Masses: From Malignancy Probability to Risk-Adapted Management

Cystic renal masses (CRMs) encompass a broad spectrum of conditions ranging from simple renal cysts to cystic renal cell carcinoma. Their detection has increased markedly with the widespread use of abdominal imaging, raising concern about potential overtreatment: many complex CRMs treated surgically are ultimately benign, while some malignant lesions are low grade, localized, and follow a relatively indolent clinical course. Although the Bosniak classification stratifies malignancy probability, translating lesion characteristics into preoperative assessments of biological aggressiveness and patient-specific clinical consequences remains challenging. Drawing on published evidence and common clinical decision-making scenarios, this Perspective outlines the pathologic classification of CRMs, examines the limitations of the Bosniak classification, and discusses the prospects for and current barriers to the use of radiomics and artificial intelligence for benign-versus-malignant classification. With the dual objectives of differentiating benign from malignant lesions and assessing biological aggressiveness, we focus on individualized management strategies that integrate the probability of malignancy, potential clinical harm, and patient-specific factors. These strategies include conservative management, indications for surgery, and selection of surgical approach. The aim is to inform more standardized and precise diagnosis and management of CRMs.