Percutaneous Image-Guided Non-Target Renal Biopsy in Cancer Patients: A Tertiary Cancer Center Experience

Objective: To assess the safety and diagnostic outcomes of image-guided, non-target renal biopsies performed in cancer patients. Materials and Methods: We retrospectively identified patients who underwent percutaneous, image-guided, non-target renal biopsy between January 2017 and December 2020 in our institution. We recorded demographics, clinical, procedural, and pathologic details. Univariate and multivariable logistic regression models were used to assess the association between various variables and diagnostic yield or development of adverse events. Results: A total of 318 biopsies were performed in 318 patients (178 male, 140 female) with a median BMI of 28.4 kg/m². Median systolic and diastolic BP at the time of biopsy were 133 mmHg and 74 mmHg, respectively. Tissue was obtained using 18-gauge needles (99%). Adverse events were documented in 57 cases (18%), with 12 cases (3.8%) classified as grade 2 or higher per SIR classification. Diagnosis was achieved in 310 biopsies (97%). The median number of the glomeruli identified by light microscopy, immunofluorescence, and electron microscopy was 25, 8, and 3, respectively, and a higher number of identified glomeruli was associated with diagnostic yield in univariate analysis, although not in multivariable analysis. Diastolic BP higher than 80 mmHg and CT imaging guidance were associated with the development of adverse events in univariate analysis, and CT use remained so in the final multivariable analysis (p < 0.001). No other variables, including pre-biopsy anticancer or immunotherapy medications, were associated with increased risk of adverse events. Conclusions: Percutaneous, image-guided, non-target renal biopsy in cancer patients using an 18-gauge needle has a high diagnostic yield and safety profile.