Single Arm Phase II Study of Fractionated Stereotatic Radiation Therapy (FSRT) for Bone Metastases in Breast Cancer
Fractionated stereotatic radiation therapy (FSRT) that very precisely delivers a high dose of radiation directly to the tumor may kill more tumor cells and cause less damage to normal tissue. The purpose of this study is to find out if FSRT is safe and effective in the treatment of metastatic spinal tumors of breast cancer.
• Diagnosis of invasive breast cancer
• Signed informed consent
• Bone metastases (confirmed by MRI within 4 weeks of enrollment).
• Paraosseous soft tissue ≤ 5cm. The tumour could involve the vertebral column, but did not have to, nor did it need to enter the spinal canal.
• KPS ≥ 40 or ECOG 0-2.
• The tumor is at least 2 mm away from the spinal cord. If the tumor is closer than 2 mm, surgical resection is required prior to FSRT or the total prescription dose of spinal cord is strictly limited.
• Failure of previous conventional external beam radiotherapy or surgery, residual tumor after surgery, medical inoperability, and refusal to undergo surgery.
• A maximum of three distinct noncontiguous spinal metastases per patient was allowed, and each of the separate sites may have involvement of 2 contiguous vertebral bodies.
• Patients have sufficient bone marrow reserve and liver and kidney function: neutrophil count ≥ 1500 cells / mm3; platelet count ≥ 70000 / mm3; hemoglobin (Hgb) ≥ 8.0 g / dl; if there is liver metastasis, AST and ALT \< 3x ULN
⁃ The interval between systemic chemotherapy is more than 2 weeks, and the side effects recovery from previous treatment ≤ grade 1
⁃ Patients receiving bisphosphonates, endocrine or targeted therapy at the same time were not included