Image-Guided Radiosurgery or Stereotactic Body Radiation Therapy in Treating Patients With Localized Spine Metastasis

OBJECTIVES:

Primary

• Determine the feasibility of successfully delivering image-guided radiosurgery or stereotactic body radiotherapy (SBRT) in patients with spine metastases in a cooperative group setting. (Phase II)
• Determine whether image-guided radiosurgery or SBRT (single dose of 16 Gy) improves pain control as measured by the 11-point Numerical Rating Pain Scale (NRPS) compared to conventional external beam radiotherapy (single dose of 8 Gy). (Phase III)

Secondary

• Determine whether image-guided radiosurgery or SBRT improves the rapidity of pain response and increases the duration of pain response at the treated site(s) compared to conventional external beam radiotherapy, as measured by the NRPS. (Phase III)
• Compare adverse events associated with these treatment regimens, as measured by NCI CTCAE v3.0 criteria. (Phase III)
• Evaluate the long-term effects (24 months) of image-guided radiosurgery or SBRT on the vertebral bone (e.g., compression fracture) and the spinal cord, as measured by MRI. (Phase III)

DETAILS:

This is a multicenter, phase II study followed by a randomized phase III study. Patients enrolled in the phase III portion are stratified according to the number of spine metastases to be treated (1 vs 2-3) and the type of tumor (radioresistant [including soft tissue sarcomas, melanomas, and renal cell carcinomas] vs other).

Phase II patients undergo MRI of the treated spine at baseline and at 3 months; phase III patients undergo MRI at baseline and at 3, 6, 12, and 24 months. Patients enrolled in the phase III portion also complete the Numerical Rating Pain Scale at baseline, at 1, 2, and 3 weeks after randomization, and at 1, 3, 6, 12, and 24 months. Patients are followed after completion of study treatment.

Inclusion criteria

• The patient must have localized spine metastasis from the C1 to L5 levels by a screening imaging study [bone scan, positron emission tomography (PET), computerized tomography (CT), or magnetic resonance imaging (MRI)] (a solitary spine metastasis; two separate spine levels; or up to 3 separate sites [e.g., C5, T5-6, and T12] are permitted.) Each of the separate sites may have a maximal involvement of 2 contiguous vertebral bodies. Patients can have other visceral metastasis, and radioresistant tumors (including soft tissue sarcomas, melanomas, and renal cell carcinomas) are eligible. See Figure 1 in Section 3.1.1. of the protocol for a depiction of eligible metastatic lesions: 1) a solitary spine metastasis; 2) two contiguous spine levels involved; or 3) a maximum of 3 separate sites. Each of the separate sites may have a maximal involvement of 2 contiguous vertebral bodies. Epidural compression (arrow) is eligible when there is a ≥ 3 mm gap between the spinal cord and the edge of the epidural lesion (see #10). A paraspinal mass ≤ 5 cm is allowed (see #11).

• There can be multiple small metastatic lesions shown in other vertebral bodies as shown in referenced diagram. The metastatic lesion of each spine should be less than 20% of the vertebral body as opposed to the diffuse vertebral involvement. These small lesions are often seen in the MRI even when bone scan or PET was negative. Most of these lesions are not clinically required to be treated and are therefore not included in the target volume of this protocol. Only the painful spine (pain score≥ 5) is to be treated .
• Zubrod Performance Status 0-2;
• Age ≥ 18;
• History/physical examination within 2 weeks prior to registration;
• Negative serum pregnancy test within 2 weeks prior to registration for women of childbearing potential;
• Women of childbearing potential and male participants who are sexually active must agree to use a medically effective means of birth control;
• MRI (contrast is not required but strongly recommended) of the involved spine within 4 weeks prior to registration to determine the extent of the spine involvement; an MRI is required as it is superior to a CT scan in delineating the spinal cord as well as identifying an epidural or paraspinal soft tissue component. Note: If an MRI was done as a screening imaging study for eligibility (see Section -1), the MRI can be used as the required MRI for treatment planning.
• Numerical Rating Pain Scale within 1 week prior to registration; the patient must have a score on the Scale of ≥ 5 for at least one of the planned sites for spine radiosurgery. Documentation of the patient's initial pain score is required. Patients taking medication for pain at the time of registration are eligible.
• Neurological examination within 1 week prior to registration to rule out rapid neurologic decline; see Appendix III for the standardized neurological examination. Patients with mild to moderate neurological signs are eligible. These neurological signs include radiculopathy, dermatomal sensory change, and muscle strength of involved extremity 4/5 (lower extremity for ambulation or upper extremity for raising arms and/or arm function).
• Patients with epidural compression are eligible provided that there is a ≥ 3 mm gap between the spinal cord and the edge of the epidural lesion.
• Patients with a paraspinal mass ≤ 5 cm in the greatest dimension and that is contiguous with spine metastasis are eligible.
• Patients must provide study specific informed consent prior to study entry.

Exclusion criteria

• Histologies of myeloma or lymphoma;
• Non-ambulatory patients;
• Spine instability due to a compression fracture;
• > 50% loss of vertebral body height;
• Frank spinal cord compression or displacement or epidural compression within 3 mm of the spinal cord;
• Patients with rapid neurologic decline;
• Bony retropulsion causing neurologic abnormality;
• Prior radiation to the index spine;
• Patients for whom an MRI of the spine is medically contraindicated;
• Patients allergic to contrast dye used in MRIs or CT scans or who cannot be premedicated for the use of contrast dye.