Most prevalent neoplasms with spinal metastases are breast, lung, prostate, kidney tumors and lymphoma.
Most common site for bone metastases.
Almost 40% of patients with cancer develop spinal metastasis during the course of their malignancy.
The thoracic spine, lumbar spine and cervical spine account for approximately 70%, 20% and 10% of spinal metastases, respectively.
Lesions can occur in the paraspinal region, bony vertebral column, epidural or subarachnoid spaces.
Spinal column accounts for 70% of all bone metastasis and is the third most common side metastases.
Conventional, palliative, short course external beam radiotherapy is considered first line standard treatment.
Complete response rates for pain with standard therapy are low, typically from 10-20%.
Stereotactic body radiotherapy in 2 daily fractions is superior to conventional beam therapy at a dose of 20 Gy in improving the complete response rate for pain.
Vertebral collapse occurs in as many as 70% of patients with metastatic cancer and myeloma.
Vertebral metastasis can cause back pain and lead to serious. Clinical consequences from compression fractures or spinal cord compression.
The risk of vertebral fracture is 5 fold greater in patients with recently diagnosed breast cancer and 36 fold greater with a soft tissue recurrence compared to a woman without breast cancer.
Approximately 50% of lesions are clinically silent.
Pain is the presentation in 90% of patients.
Patients suffer with pain and may have neurological complications, including metastatic epidural spinal cord compression.
Pain secondary to nociceptors activation induced by periosteal stretching by the tumor, tumor induced nerve stimulation in the endosteum, osteolysis and acidotic microenvironment caused by apoptosis of cancer cells in the filled intramedullary space.
Untreated vertebral body compression fractures can lead to adjacent level collapse, spinal cord compromise, and intractable pain.
The risk of vertebral fracture is 5 fold greater in patients with recently diagnosed breast cancer and 36 fold greater with a soft tissue recurrence compared to a woman without breast cancer.
Can cause severe pain, pathologic fractures, hypercalcemia, spinal cord compression, neurologic symptoms, decreased bone density, decreased strength, and stiffness.
Can cause deformation of the vertebra, instability of the spine, kyphosis, and fracture.
Risk for new vertebral fractures related to the number and severity of vertebral deformities.
Radiotherapy effectively controls pain for the majority of patients with spinal metastases.
Treatment for spine metastasis not requiring or amenable to surgery includes conventional, external beam, radiotherapy with palliative radiation doses.
High-dose radiotherapy, however that may be needed for durable tumor control and prevention of bone destruction of the spiral column is precluded by sensitivity of the sponal cord to radiation.
Conventional external beam radiation provides sub optimal rates of local control and pain relief for patients with longer life expectancies.
The use of conventional technique radiation therapy also precludes re-irradiation.
Stereo topic body radiation therapy for spinal lesions is an effective primary or salvage therapy for mechanically stable spinal metastases.
SBRT using image guidance can deliver high dose radiation precisely, with a steep dose gradient at the interface between spinal cord and tumor in spinal cord metastases, creating a therapeutic window by lowering the risk for spinal cord myelopathy.
In spinal metastases SBRT can be used instead of surgery, allowing patients to avoid perioperative risk factors such as bleeding infection and anesthesia.
Targeted radioablation therapy effective for pain palliation.
A phase 3 randomized clinical trial of 339 patients found the radiosurgery was not superior in terms of pain response at three months, and in fact, worse pain response was observed, compared with conventional external beam radiation therapy for vertebral metastasis (Ryu S).