Radiation exposure during percutaneous ablation of small renal masses: A multi-institutional multimodality analysis

Abstract Objective: To understand the effective radiation dose during percutaneous cryoablation (CA) and radiofrequency ablation (RFA) and characterize variables that may affect the individual dose. Materials and Methods: The effective radiation dose was determined by conversion of the dose–length product from CT scans performed during percutaneous CA or RFA for patients with solitary renal masses (<4 cm) at four academic centers. Radiation dose per case was compared between patients and institutions using multivariate and univariate analysis. Lifetime attributable risk of cancer was calculated for each institution and utilized to determine the number needed to harm for a range of ages at the time of exposure. Results: One hundred twenty-three patients met the inclusion criteria with a mean age of 71 years. Sixty-nine percent of patients were male, mean body–mass index (BMI) was 29.4, and mean tumor size was 2.2 cm. The mean effective radiation dose per ablation was 40 mSv (range 3.7–147). On multivariate...