A Phase II Study of Spinal Radiosurgery

A Phase II Study of Spinal Radiosurgery

Phase I of the study (motion and quality assurance [QA] study) is being used to determine intrafraction target motion and define quality assurance procedures for single fraction spinal radiosurgery. The Phase II portion of the study is being used to estimate the palliative response (pain or relief of neurologic symptoms) and local control for single fraction radiosurgery delivered with TomoTherapy and to assess the acute and late toxicity of spinal radiosurgery.

Optimal radiation plan is generated that treats the tumor (CTV) and spares normal tissue, especially the spinal cord. Motion and QA study will determine intrafraction motion for phase II portion of the study.

Dose prescription to tumor is based upon maximal dose received by 0.5 cc of spinal cord and whether patient has had prior radiation therapy to that area:

Phase I - Motion and QA Study: 20-25 Gy in 5 fractions/10-20 patients/previous RT = <50% CTV dose/No previous RT = <80% CTV dose.

Phase II - 9-24 Gy in 1 fraction/30 total in order to have 20 evaluable patients (15 patients with prior RT and 15 without prior RT/previous RT = 8 Gy/No previous RT = 10 Gy.

# Motion and QA study will treat CTV to 20-25 Gy in 5 fractions to study intrafraction motion for QA of single fraction administration. This will define treatment margins for single fraction radiosurgery.

*Previous RT:

• greater than six months since completion of RT
• at least 20 Gy, but no more than 50 Gy

Inclusion Criteria:

1. All subjects must have history of histologically confirmed neoplasm or radiographically-diagnosed AVM. Patients without a prior tissue diagnosis but who have a radiographically characteristic lesion are eligible if there is consensus agreement of the diagnosis in the UAB Neuro-oncology Tumor Board.
2. ECOG performance status of less than or equal to 2
3. Age greater than 18
4. Life expectancy greater than 12 weeks
5. Subjects given written informed consent

Exclusion Criteria:

1. Cytotoxic chemotherapy within 7 days of treatment
2. Insufficient recovery from all active toxicities of prior therapies
3. Epidural spinal cord compression requiring immediate neurosurgical decompression. If a patient requires immediate surgery for neurologic compromise, they may still be eligible post operatively if tumor was incompletely resected.
4. Patient is non-ambulatory. Optimization of pretreatment neurologic function with steroids is allowed. Ambulation with assistance of walker or cane is allowed.
5. Patient is pregnant and it is judged by the treating Radiation Oncologist that spinal radiosurgery would place the fetus in unacceptable danger.