Percutaneous microwave ablation for local control of metastatic renal cell carcinoma.

PURPOSE: The purpose of the article is to evaluate the safety and oncologic efficacy of microwave ablation for metastatic renal cell carcinoma (mRCC).

MATERIALS AND METHODS: From September 2011 to December 2016, 33 mRCC were ablated in 18 patients using percutaneous microwave ablation. Sites of mRCC include retroperitoneum (n = 12), contralateral kidney (n = 6), liver (n = 6), lung (n = 5), adrenal gland (n = 5). Technical success, local, and distant tumor progression, and complications were assessed at immediate and follow-up imaging. The Kaplan-Meier method was used for survival analysis.

RESULTS: Technical success was achieved for 33/33 (100%) mRCC tumors. Ablation provided durable local control for 28/30 (93%) mRCC tumors in 17 patients at a median duration of clinical and imaging follow-up of 1.6 years (IQR 0.7-3.6) and 0.8 years (IQR 0.5-2.7), respectively. In-hospital and perioperative mortality was 0%. There were 5 (15%) procedure-related complications including one high-grade event (Clavien-Dindo III). Four patients have died from mRCC at a median of 1.3 years (range 0.7-5.1) following ablation. Estimated OS (95% CI number still at risk) at 1, 2, and 5 years were 86% (53-96%, 11), 75% (39-92%, 8), and 75% (39-92%, 3), respectively.

CONCLUSIONS: Microwave ablation of oligometastatic renal cell carcinoma is safe and provides durable local control in appropriately selected patients.