Comparing radiation exposure between ablative therapies for small renal masses

Area of Science:

• Urology
• Interventional Radiology
• Medical Physics

Background:

• Small renal masses (<4 cm) are increasingly detected, necessitating minimally invasive treatment options.
• Percutaneous ablation techniques, including cryoablation (PCA) and radiofrequency ablation (PRFA), offer alternatives to surgery.
• Quantifying radiation exposure associated with these procedures is crucial for patient safety and informed consent.

Purpose of the Study:

• To evaluate and compare the radiation exposure in patients with small renal masses undergoing percutaneous cryoablation (PCA) versus percutaneous radiofrequency ablation (PRFA).
• To assess radiation doses received during both the treatment phase and the first year of follow-up.

Main Methods:

• Retrospective review of patients with small renal masses (<4 cm) treated with PCA or PRFA over a 7-year period at a single academic center.
• Comparison of pre-operative, operative, and post-operative variables, including radiation exposure.
• Statistical analysis using Mann-Whitney U and Pearson Chi-Square tests (p<0.05 significance).

Main Results:

• No significant differences were observed in pretreatment parameters or oncologic outcomes between PCA and PRFA groups.
• Average radiation exposure during PCA treatment was significantly higher (39.7 mSv) compared to PRFA (22.2 mSv) (p=0.001).
• Total estimated radiation exposure (treatment + 1-year follow-up) was higher for PCA (134.5 mSv) than PRFA (117 mSv) when routine CT imaging was used.

Conclusions:

• This study is the first to quantify radiation exposure for PCA and PRFA in small renal masses.
• The substantial radiation doses necessitate inclusion in the informed consent process for these procedures.
• Caution is advised when using these technologies in pediatric patients due to their increased susceptibility to long-term radiation effects.