Percutaneous Microwave Ablation Versus Robot-Assisted Partial Nephrectomy for Stage I Renal Cell Carcinoma: A Propensity-Matched Cohort Study Focusing Upon Long-Term Follow-Up of Oncologic Outcomes.

PURPOSE: To retrospectively compare long-term oncologic outcomes of percutaneous computed tomography-guided microwave ablation (MWA) and robot-assisted partial nephrectomy (RAPN) for the treatment of stage 1 (T1a and T1b) renal cell carcinoma (RCC) patients. MATERIALS AND METHODS: Institutional database research identified all T1 RCC patients who underwent either MWA or RAPN. Models were adjusted with propensity score matching. Kaplan-Meier log-rank test analyses and Cox proportional hazard regression models were used to compare the oncologic outcomes. Patient and tumor characteristics, technical success as well as oncologic outcomes were evaluated and compared between the 2 groups. RESULTS: After propensity score matching, a total of 71 patients underwent percutaneous MWA (mean age 70 ± 10 years) and 71 underwent RAPN (mean age 60 ± 9 years). At 8-year follow-up, the estimated survival rates for MWA cohort were 98% (95% confidence interval [CI] 95-100%) for overall survival, 97% (95% CI 93-100%) for recurrence-free survival, and 97% (95% CI 93-100%) for metastasis-free survival. The matched cohort that underwent RAPN exhibited survival rates of 100% (95% CI 100-100%) for overall survival, 98% (95% CI 94-100%) for recurrence-free survival, and 98% (95% CI 94-100%) for metastasis-free survival. After performing log-rank testing, these rates were not significantly different (p values of 0.44, 0.67, and 0.67, respectively). CONCLUSION: The results of the present study suggest that both MWA and RAPN are equally effective in terms of oncologic outcome for the treatment of T1 RCC.

Standards of practice: quality assurance guidelines for percutaneous treatments of intervertebral discs.

Percutaneous treatments are used in the therapy of small- to medium-sized hernias of intervertebral discs to reduce the intradiscal pressure in the nucleus and theoretically create space for the herniated fragment to implode inward, thus reducing pain and improving mobility and quality of life. These techniques involve the percutaneous removal of the nucleus pulposus by using a variety of chemical, thermal, or mechanical techniques and consist of removal of all or part of nucleus pulposus to induce more rapid healing of the abnormal lumbar disc. These guidelines are written to be used in quality improvement programs for assessing fluoroscopy- and/or computed tomography-guided percutaneous intervertebral disc ablative techniques.