Plasma DNA Methylation for Preoperative Classification of Renal Masses

Inclusion Criteria:1.Age 18 years or older. 2.A renal mass identified by computed tomography and/or magnetic resonance imaging. 3.Partial nephrectomy or radical nephrectomy planned as part of routine clinical care. 4.Preoperative peripheral blood collection feasible before surgery or other treatment of the index lesion. 5.Final postoperative histopathological diagnosis expected to be available. 6.Written informed consent provided. \- Exclusion Criteria:7.Systemic anticancer therapy, radiotherapy, local ablation, or surgery/pathological sampling of the index renal lesion before study blood collection. 8.Concurrent active malignancy requiring systemic treatment that, in the investigator's judgment, could materially interfere with interpretation of the methylation assay. 9.Severe acute infection or another uncontrolled systemic condition that could compromise biospecimen quality or study procedures. 10.Inadequate preoperative blood specimen or failure of prespecified analytical quality-control requirements. 11.No definitive pathological diagnosis of the index renal lesion. Any condition that, in the investigator's judgment, makes participation inappropriate. \-