Diagnostic Accuracy and Risks of Biopsy in the Diagnosis of a Renal Mass Suspicious for Localized Renal Cell Carcinoma: Systematic Review of the Literature.

PURPOSE: Clinical practice varies widely on the diagnostic role of biopsy for clinically localized renal masses suspicious for renal cell carcinoma. Therefore, we performed a systematic review of the available literature to quantify the accuracy and rate of adverse events of renal mass biopsy.
MATERIALS AND METHODS: MEDLINE®, Embase® and the Cochrane databases were searched (January 1997 to May 2015) for relevant studies. The systematic review process established by the Agency for Healthcare Research and Quality was followed. Nondiagnostic biopsies were excluded from diagnostic accuracy calculations.
RESULTS: A total of 20 studies with 2,979 patients and 3,113 biopsies were included in the study. The overall nondiagnostic rate was 14.1% with 90.4% of those undergoing surgery found to have malignancy. Repeat biopsy led to diagnosis in 80% of patients. The false-positive rate was low (4.0%), histological and renal cell carcinoma subtype concordance was substantial, and Fuhrman upgrading notable (16%) from low grade (1 to 2) to high grade (3 to 4). Core biopsy was highly sensitive (97.5%, CI 96.5-98.5) and specific (96.2%, CI 90.7-100) when a diagnostic result was obtained, but most patients (∼80%) did not undergo surgery after a benign biopsy. Among patients undergoing extirpation 36.7% with a negative biopsy had malignant disease on surgical pathology (negative predictive value 63.3%, CI 52.4-74.2). Direct complications included hematoma (4.9%), clinically significant pain (1.2%), gross hematuria (1.0%), pneumothorax (0.6%) and hemorrhage (0.4%).
CONCLUSIONS: Diagnostic accuracy was generally high for biopsy of localized renal masses with a low complication rate, but the nondiagnostic rate and negative predictive value were concerning. Renal mass sampling should be used judiciously as further research will determine its true clinical utility.