Radiofrequency ablation (RFA) was introduced in 1990, but the scope and value of its application in the treatment of substantial tumors has only attracted great attention in recent years. 2001, the NIH started a clinical study on the scope of phase II clinical application of RFA for tumor treatment. At present, the treatment field of RFA has been extended from the initial liver tumor to soft tissue masses such as lung, kidney, adrenal gland, bone, thyroid and breast. This paper reports the experience and results of cold circulation RFA treatment for 23 patients with solid tumors in the chest from September 2003 to July 2006 in our department. 1. Data and parties 1.1 General data: Among the 23 tumor patients, 17 had primary lung cancer, 3 had metastatic lung cancer, 2 had mediastinal neurogenic tumors, and 1 had thyroid cancer chest wall metastasis. The age ranged from 38 to 75 years old, with a mean age of 57.2 years old, including 17 cases of men and 6 cases of women. The diagnosis was based on clinical diagnosis, surgical pathology, and biopsy pathology. 1.2 Instruments and equipment: The Cool-tip RF tumor inactivation treatment system from Radionics, which has a 100w RF generator and a set of cold circulation equipment, and is equipped with two kinds of RF electrode needles: monopolar RF with a maximum diameter of 3cm and multipolar RF with a maximum diameter of 5cm. 21 cases of RF treatment were performed on SIMENS CT machine. machine, and 2 cases were treated with radiofrequency under direct vision for open-heart surgery. 1.3 Treatment: Patients were preoperatively injected with luminal 1mg and atropine 0.5mg intramuscularly and intraoperatively with 2% lidocaine local anesthesia. Two cases of central lung cancer were treated with radiofrequency under direct vision for open-heart surgery under general anesthesia, and the large blood vessels in the hilar region were avoided during radiofrequency puncture. The remaining 21 cases were treated by inserting RF electrode needles under CT-guided percutaneous puncture. For lesions less than 3 cm in diameter, the RF electrode needles were passed through the center of the lesion as far as possible, and the needle tips reached the edge of the lesion as far as possible. For larger lesions, the angle can also be changed to perform 2-3 repetitions of RF. Each radiofrequency 12 minutes. 1.4 Observation of efficacy: Postoperative observation of patients’ symptom improvement and complications, and re-examination of CT at 1, 3, 6 and 12 months after surgery to understand the destruction of tumor foci and whether there are residual tumor foci, and if necessary, the second radiofrequency treatment. 2. Results 2.1 General: In this group of 23 patients, there were 22 pulmonary lesions (2 cases with two metastases in the lung), 2 mediastinal lesions and 1 chest wall lesion. Among them, 9 cases received single monopolar radiofrequency, 3 cases received multiple monopolar radiofrequency, 8 cases received single multipolar radiofrequency, and 3 cases received multiple multipolar radiofrequency. 2.2 Destruction of tumor foci: CT scans of lung tumors after intraoperative radiofrequency showed a 20%-50% increase in the shadow of the foci, with foci of gasification visible in some of the foci and exudative inflammatory changes in the peripheral lung tissue (Figure 1-6). Two patients with intraoperative radiofrequency showed carbonization in the periphery of the tumor and partial pneumatization in the center and exudative changes on the surface of the tumor under direct vision (Figure 7-9). The CT review 3 months after surgery showed that the tumor foci were reduced > 1/2 of the original tumor body in 15 cases, and the tumor foci were reduced 1/2 of the original tumor body), and effective in 7 cases (reduced)