Stereotactic ablative radiation therapy: Role in treatment of liver metastases

There is a wide variety of minimally invasive tumor ablation technologies available for the management of liver tumors, including liver metastases. These treatments offer an alternative to surgical intervention in non-surgical candidates. The most commonly used ablation modalities make use of extreme heat to induce tumor necrosis. Although radiation has traditionally held a minor role in treatment of liver tumors, high-dose hypofractionated irradiation typically delivered with image-guidance is a new treatment modality with promising early results. This article will review the fundamental principles of ablative radiation therapy, compare it with other existing ablation technologies, and review early clinical results.