Stereotactic intensity-modulation radiation therapy for vertebral body and paraspinal tumors

Therapeutic doses of radiation for paraspinal tumors are often limited by the dose-related tolerance of the spinal cord. Intensity-modulated radiation therapy (IMRT) is an advanced form of three-dimensional conformal radiation therapy that provides improved coverage of tumor volumes while reducing the radiation dose to the spinal cord. Computer-controlled multileaf collimation provides high conformality, which makes it feasible to treat tumors of any shape, even those that are wrapped around the spinal cord. The use of a newly developed, noninvasive body frame, the capability of fusing computerized tomography and magnetic resonance images, and on-line portal films provide precise target immobilization and target identification. In this paper the authors discuss their preliminary experience in six cases in which IMRT was used to treat paraspinal lesions in patients who harbored locally recurrent tumors and/or tumors that previously received the maximum doses of radiation that could be tolerated by the spinal cord.