Background: In spite of recent advances in cancer therapy, treatment of primary and metastatic tumors of liver remains 
a significant challenge to the health care community worldwide. Surgical resection is considered the gold standard for 
treatment of liver tumors; however, the majority of patients are not candidates for surgical resection. 
Aim: The study aims at evaluation of the role of radiofrequency ablation in the treatment of primary and metastatic liver 
tumors in patients who are not candidates for surgery. 
Patients and methods: For nine months, patients with primary or metastatic liver tumors, that were excluded from surgical treatment, were subjected to radiofrequency thermal ablation. Three cases of this series were excluded due to anatomical considerations and advanced disease. The study included 35 focal lesions in 21 patients. After the lesions were identified and biopsied, they were thermally ablated. The ablation zone was evaluated by comparing preoperative triphasic CT scanning of the liver with postoperative scan obtained one month after ablation. 
Results: The procedure was completed in all patients without complications. Twenty lesions were primary liver tumors while fifteen lesions were metastatic. The mean tumor diameter was (2.5+1.1mm) and the average number of lesions per patient was (1.67+0.7) ranging from one to three masses. Thirty-three lesions were treated with a single ablation session including overlapping technique in seven lesions while two lesions required a second session. Fifteen patients received percutaneous ablation while six patients received intraoperative ablation. The follow-up period ranged from 3 to eight months without any reported cases of recurrence; however, two new lesions appeared in two patients that were scheduled for another session of ablation. 
Conclusion: Radiofrequency ablation offers a new safe technology that should be considered for treatment of liver tumors when surgery is not a valid option.