Percutaneous renal mass biopsy at Siriraj Hospital: A retrospective study

Background: Limited data on renal mass biopsies are available from Asian regions, most specifically from developing countries.
Objective: To assess the diagnostic yield of percutaneous renal mass biopsy, factors related to diagnostic yield, and immediate complications associated with the biopsy procedure.
Methodology: A single-center retrospective observational study included 144 patients who underwent 146 consecutive imaging-guided renal mass biopsies from January 2018 to June 2023. The biopsy outcomes were classified into diagnostic and nondiagnostic groups. Patient characteristics, renal mass variables, and biopsy procedure-related variables were compared to assess their significant associations with biopsy outcome. Multivariate logistic regression analysis was performed to identify an independent predictor of diagnostic biopsy.
Results: The initial biopsy result was diagnostic in 91.1% (133/146) of patients, out of which 15% were benign and 85% malignant lesions. Repeat biopsy was performed in 3/13 initial nondiagnostic cases, yielding 100% diagnostic results and an overall diagnostic yield of 93.2%. The renal mass composition, size, and the number of core biopsies were significantly associated with diagnostic biopsy outcome (p value < 0.05). The number of core biopsies significantly predicted the diagnostic biopsy results according to multivariate regression analysis (OR=0.533, CI 0.299–0.952, p=0.033). The concordance of biopsy results with available surgical histopathology reports was 92.3% (24/26), after excluding the two surgically resected specimens from initial non-diagnostic results. The immediate complications were documented in 14.4% (21/146) of patients with 11.6% mild adverse events (perinephric hematoma, perilesional and subcapsular hematoma) and 2.7% severe adverse events (expanding hematoma/ active bleeding) according to the Society of Interventional Radiology adverse event classification.
Conclusion: Considering its high accuracy and low complication rate, percutaneous renal mass biopsy can play an important role in risk stratification and guide appropriate management plans in patients with renal masses, thereby avoiding overtreatment and preventing complications associated with surgery.