Background There is genuine need to develop interventional treatment options for management of lung tumors. Radiofrequency ablation (RFA) is one such alternative being promoted to treat lung tumors recently. Larger studies should help define RFA's further development. Furthermore fluorodeoxyglucose positron emission tomography (PET) has been reported to be an accurate indicator of treatment response in variety of tumors. This study focuses on the evaluating the feasibility of RFA and usefulness of PET scan in lung tumors after RFA procedure. Patients and methods Between November 1999 and May 2002, 50 patients with primary or metastasis pulmonary tumors underwent RFA procedure. The electrode was guided to the target areas using computerized tomography (CT). Tumors smaller than 3.5 cm were given single RFA, while tumors larger than 3.5 cm received RFA to multiple sites. Maximum 4 lesions or 6 target areas were treated during one operating procedure. Whole body and/or lung PET images were acquired; identical site CT images and chest X-ray were taken 1 week before and after RFA. Results Of the 50 patients, 17 had single lesions while rest had multiple lesions. Tumors smaller than 3.5 cm were completely dissipated after RFA. In tumors larger than 3.5 cm, the part within 3.5 cm diameter dissipated. While CT showed that tumor image became larger 1 to 2 weeks after RFA procedure. PET demonstrated tumor destruction in 70% cases, compared to 38% in CT. Conclusion The present study shows RFA to be safe and effective treatment option for lung tumors. PET is superior to CT in evaluation the effectiveness of RFA treatment shortly after the procedure.