Role of tumor location in selecting patients for percutaneous versus surgical cryoablation of renal masses

Introduction: To characterize the relationship between tumor location and choice in selecting surgical cryoablation (SCA) versus percutaneous cryoablation (PCA) for treatment of renal masses. Materials and methods: MEDLINE search was performed to identify studies in which cryoablation was used as therapy for renal masses. Tumor location was stratified as anterior, posterior, or lateral. Lesions were also described by endophycity (endo-, meso-, or exophytic) and polarity (upper, mid, or lower pole). Treating specialty was stratified as urology, radiology, or both. Comorbidity reporting rates were indexed for each manuscript. Results: Thirty-seven manuscripts included 2344 lesions treated by SCA or PCA formed the basis for the analysis. Comparing SCA versus PCA series, anterior/posterior designation was reported in 31% versus 47% of series; endophycity designation was reported in 17% versus 40% of series; and polarity designation was reported in 48% versus 47% of series (all p values > 0.05). Amongst those lesions treated by SCA, 44% were anterior lesions and 28% were posterior, while among PCA-treated lesions 9% were anterior and 81% were posterior. Tumor location description was entirely absent in 32% (14/44) of published series. Conclusions: Despite data that tumor location is integral to choice of treatment for renal mass, anatomic tumor descriptors are vastly underreported in the cryotherapy literature. Nearly one third of masses treated with SCA are on the posterior surface of the affected kidney, and may be amenable to PCA, thus avoiding risk of general anesthesia and intraabdominal dissection in comorbid cohorts. Better reporting of objective measures of tumor anatomy and location in cryosurgery literature may facilitate standardization of treatment protocols in patients with renal mass.