Percutaneous cryoablation (PCA) of renal masses in patients with significant comorbidities is a safe and oncologically effective alternative to extirpative surgery, according to researchers.
Eric H. Kim, MD, and colleagues at Washington University School of Medicine in Saint Louis, Mo., reviewed the outcomes of 124 patients treated with PCA for a total of 129 renal tumors. The treatment success rate was 87% after a mean follow-up of 30 months, a rate in line with previous published studies, the investigators reported online ahead of print in BJU International.
Patients had a mean age of 72.6 years and a mean tumor size of 2.7 cm. Of the 124 patients, 11 (9%) experienced complications.
In multivariate analysis, patients aged 70 years or older had a significant 4.3 times increased risk of renal disease progression after PCA compared with younger patients. Those with a tumor in the hilar location had a significant 4.7 times increased risk, and patients with an estimated glomerular filtration rate of 60 mL/min/1.73 m2 or less on post-operative day 1 had a significant seven times increased risk. Additionally, a tumor size of 3 cm or greater was associated with a significant 3.2 times increased risk of PCA failure compared with smaller tumors.
The major limitation of the study is the relatively few biopsies performed (18% of tumors), Dr. Kim’s team pointed out. Evaluation of tumor control was based on radiographic studies without pathologic confirmation, similar to other studies of percutaneous ablative treatments. Other limitations included the retrospective study design, relatively small sample size, and limited follow-up. Their study represents the largest PCA series, but “the sample size limits interpretation of the analyses because of the low rate of treatment failure for PCa,” they wrote.
Although their study has one of the longest mean follow-ups, the researchers noted, the slow growth of most renal tumors requires longer-term studies with even more substantial follow-up.