Inclusion Criteria:

- Patients with a spinal metastasis who will be treated with Cyberknife radiosurgery.

- There are no age or gender restrictions.

- There are no life expectancy restrictions.

- Karnofsky Performance Status greater than 40.

- Negative pregnancy test or clinically assessed as not pregnant.

- Ability to understand and the willingness to sign a written informed consent
document.

Exclusion Criteria:

- Patients with benign tumors will not be included (neurofibromas, schwannomas, etc.)

- Other investigational medications or treatments will be noted, but will not preclude
inclusion.

- Pregnant or nursing patients will be not be included in the study due to radiation
exposure.