Figure 12a. Small squamous cell lung cancer of the right upper lobe in a 78-year-old man. The patient was undergoing home oxygen therapy and was a poor candidate for surgery or irradiation. (a) CT scan obtained with the patient prone shows a mass into which a single RF electrode has been inserted. (b) Conventional radiograph shows a chest tube that was required because of development of a pneumothorax. The patient underwent 1 week of chest tube treatment. Extensive subcutaneous emphysema is also noted.