Figure 8c. Nasopharyngeal carcinoma metastatic to the mediastinum in a 52-year-old man. The patient refused additional radiation therapy and chemotherapy. RF ablation was performed to retard tumor growth and prevent involvement of the left hilum. CT scan obtained prior to RF ablation showed a safe window for ablation adjacent to the manubrium of the sternum. (a) CT fluoroscopic image shows a mass into which a cluster RF electrode has been inserted. The untreated tumor grew, and a second RF ablation procedure was performed 7 months later. (b, c) Follow-up CT scans show a large tumor cavity that communicates with the left upper lobe bronchus. Note also the peripheral contrast-enhanced tumor tissue.