Radiofrequency Thermal Ablation of Breast Cancer Local Recurrence: A Phase II Clinical Trial

Background: The role of radiofrequency (RF) ablation to treat local recurrence of breast cancer is unknown. Methods: We conducted a two-stage phase II clinical trial. Eligible patients had a histologically confirmed noninflammatory and <= 3 cm ipsilateral breast tumor recurrence. The tumor site was identified by intraoperative sonography. A LeVeen needle electrode (RadioTherapeutics Corp, Mountain View, Calif) was inserted into a single site within the tumor and radiofrequency ablation was performed using a RF-2000 generator (RadioTherapeutics Corp). After completion of radiofrequency, a mastectomy was performed. Conventional staining and nicotinamide adenine dinucleotide-diaphorase (NADH-diaphorase) cell viability staining were performed. Results: During the first stage, procedures were uneventful. Conventional, cytokeratin, and NADH-diaphorase staining identified persistent viable tumor cells in the RF-ablated region in three patients. This phase II trial was stopped after completion of the first stage because of insufficient efficacy. Conclusion: We demonstrate in this study that RF ablation is a potential technique to destroy local recurrence of breast tumors but the technique we tested in this phase II clinical trial had insufficient efficacy to recommend its use in routine.