Irradiation of spinal metastases: should we continue to include one uninvolved vertebral body above and below in the radiation field?

Purpose: Historically, the appropriate target volume to be irradiated for spinal metastases is 1-2 vertebral bodies above and below the level of involvement for three reasons: (1) to avoid missing the correct level in the absence of simulation or (2) to account for the possibility of spread of disease to the adjacent level, and (3) to account for beam penumbra. In this study, we hypothesized that isolated failures occurring in the level adjacent to level treated with stereotactic body radiosurgery (SBRS) were infrequent and that with improved localization techniques with image-guided radiation therapy, treatment of only the involved level of spinal metastases may be more appropriate.

Methods And Materials: Patients who had received SBRS treatments to only the involved level of the spine as part of a prospective trial for spinal metastases comprised the study population.