Simple Renal Cysts and Aortic Aneurysms: From Imaging Markers to Prognostic Indicators of Postoperative Outcomes.

Simple renal cysts (SRCs) have traditionally been regarded as benign, age-related incidental findings with limited clinical significance. However, accumulating evidence suggests that SRCs are associated with abdominal aortic aneurysm (AAA), thoracic aortic aneurysm (TAA), and aortic dissection (AD), indicating that they may reflect systemic extracellular matrix (ECM) degeneration rather than isolated renal aging. This narrative review summarizes the current evidence linking SRCs to aortic disease, explores the underlying biological mechanisms, and discusses their potential prognostic significance following endovascular aortic repair. Observational studies have consistently reported a 2- to 3-fold higher prevalence of SRCs in patients with aortic disease compared with controls. Shared mechanisms, including ECM remodeling, matrix metalloproteinase activation, genetic susceptibility, and arterial stiffening, provide biological plausibility for this association. Emerging evidence further suggests that SRCs are independently associated with reduced sac shrinkage after endovascular aneurysm repair (EVAR) and thoracic endovascular aortic repair (TEVAR), as well as with an increased risk of aortic-related adverse events following TEVAR for type B AD. Although the current evidence is derived predominantly from retrospective studies, SRCs represent a readily identifiable imaging marker that may enhance risk stratification and postoperative surveillance. Prospective multicenter studies are warranted to validate these findings and clarify their clinical implications.