Treatment of bone metastases with microwave thermal ablation.

PURPOSE To retrospectively evaluate the feasibility, safety, and effectiveness of computed tomography (CT)-guided percutaneous microwave ablation (MWA) in patients with bone metastases. MATERIALS AND METHODS Twenty-one patients with metastatic bone lesions were treated in 18 MWA sessions. In patients whose lesions contained fractures, or who had a high risk for fracture (48%; n = 10), MWA was followed by cementoplasty with polymethylmethacrylate injection. The positioning of the MWA antenna into the tumor was guided by CT. Treatments were performed under conscious sedation. All patients underwent clinical (self-reported Brief Pain Inventory [BPI]; scale from 0 to 10) and radiologic evaluation at baseline and 1 month after the procedure. The reported results are data from baseline to a follow-up period of 3 months. RESULTS There were no complications. A reduction of pain and improvement in quality of life was observed in all patients as measured by BPI score. On average, the mean BPI score during the 3-month follow-up period was reduced by 92% (41%-100%). Thirteen of 18 patients (72%) were symptom-free, four patients (22%) were still symptomatic but with 85% lower average BPI scores (41%-95%), and one patient (6%) experienced a recurrence of symptoms. CONCLUSIONS Preliminary results suggest that MWA of bone metastases is a well tolerated, safe, and effective procedure. However, its efficacy still remains to be determined by medium- and long-term studies.