Systematic Review and Meta-analysis on Renal Tumor Biopsy: Accuracy, Safety, and Impact on Clinical Decision-making

BACKGROUND AND OBJECTIVES: We performed a systematic review and meta-analysis to evaluate the diagnostic accuracy, safety, and clinical impact of renal tumor biopsy (RTB) in managing renal cell carcinoma. METHODS: MEDLINE, Embase, and Cochrane CENTRAL were systematically searched for studies evaluating diagnostic accuracy, complications, and clinical impact of RTB. Diagnostic performance was synthesized using hierarchical bivariate random-effects models; concordance between biopsy and surgical specimens was assessed using pooled proportions that were estimated using random-effects meta-analysis. Risk of bias was evaluated with QUADAS-2. KEY FINDINGS AND LIMITATIONS: Overall, 103 studies were included. The pooled diagnostic yield of RTB was 90%. Summary sensitivity and specificity for malignancy were 99% and 85%, respectively. Concordance between RTB and surgical pathology was high for benign versus malignant (96%) and histological subtype (89%), but moderate for grade (four-tier: 64%; two-tier: 78%). The overall complication rate was low (3%), with negligible (<1%) Clavien-Dindo ≥3 complications and 1% bleeding events (with only two patients requiring embolization). Tumor seeding was reported only in one study with a pooled seeding proportion of 0%. RTB findings was associated with a change in clinical management in 39% of patients and avoidance of active treatment in 28%. Most studies were at high risk of bias, mainly due to patient selection and flow/timing, and were predominantly retrospective. CONCLUSIONS AND CLINICAL IMPLICATIONS: RTB is safe and high-yield, with excellent sensitivity, high concordance for benign vs malignant and histotype, but only moderate reliability for tumor grade. RTB is therefore an important aid in refining diagnosis in patients with a renal mass and supporting individualized decision-making.