Bone is one of the most frequent sites of metastasis and the spine is the most common of painful skeletal sites [25
]. Spinal metastases are found in more than 2/3 of patients who die of cancer [15
]. Vertebrae are therefore frequently affected by pathologic fractures, in 10% to 20% of cases involving the posterior wall of the vertebral body [16
], which can protrude posteriorly and cause spinal canal compromise and neurologic injury [16
]. Thoracic vertebrae are the most common sites of disease (60%–80%), followed by lumbar (20%) and cervical spine (10%) [15
] classified patients with spinal metastases into the following five categories, according to the extent of neurologic compromise and bone destruction: Class 1, no major neurologic involvement; Class 2, involvement of bone without collapse or instability; Class 3, major neurologic impairment (sensory or motor) without major involvement of bone; Class 4, vertebral collapse with pain due to mechanical causes or instability but without major neurologic compromise; and Class 5, vertebral collapse or instability combined with major neurologic impairment. Treatment is palliative and aims to relieve pain, prevent development of any pathologic fracture, improve mobility and function, and, if possible, prolong survival [17
]. The initial therapeutic option (Classes 1 and 2) is a nonoperative treatment based on rest, bracing, chemotherapy/hormonal treatment, and analgesics, but in the presence of refractory pain, spinal instability or neurologic deficit from cord compression (Classes 4 and 5), surgical stabilization is necessary. Patients in Class 3 are initially treated with radiotherapy alone, but similar to those in Classes 4 and 5, they do not always respond [27
]. Furthermore, life expectancy is an important factor to justify surgical treatment, and generally, indications include a life expectancy of greater than 6 months and isolated metastasis [3
]. Radiation therapy provides local pain control in a high percentage of cases and works best if combined with chemotherapy. The aim of radiotherapy for patients with a short life expectancy may be different from that for those who have a better prognosis and require not only pain relief but also spinal function [27
]. Since its efficacy is dose-dependent, to obtain longer-lasting results, a high dose of irradiation may be required and the adverse effects of radiation therapy (eg, radiation myelitis) must be considered. Furthermore, the pain-relieving effect of radiation therapy is gradual and local response rates after repeated radiotherapy due to recurrent pain symptoms at the same port drastically decrease after the first course.
Few patients with neoplastic vertebral fractures are surgical candidates; therefore, current treatments are aimed at pain palliation and prevention of complications [25
]. Standard treatment includes analgesics, mainly opioids, and radiation therapy. However, more than 20% to 30% of patients are nonresponsive [17
], and in this case, patients are exposed to a number of deleterious consequences, such as impairment of function and quality of life, decreased mobility, and depression [26
]. Percutaneous vertebroplasty (PVP) is currently considered a reasonable alternative for treating vertebral fractures of the thoracic and lumbar spine since polymethylmethacrylate (PMMA) injection inside the vertebral body provides both pain control in approximately 97% of patients and vertebral stabilization [8
However, in the cervical spine, PVP is technically challenging because of the potential complications related to the complex anatomy of this region (spinal cord, jugular vein, cranial nerves, carotid artery, and vertebral artery). Furthermore, in the case of osteolytic lesions, the risk of cement leakage is increased, which, when involving the spinal canal, may compromise the spinal cord or nerve roots, leading to severe neurologic deficit. At present, cervical spine percutaneous vertebroplasty has been only anecdotally reported to treat lesions in selected patients with cervical lesions (Cortet et al. [8
] reported only five cases in the cervical spine), and since most cases have been in the thoracic and lumbar spines it is not known whether the procedure is technically feasible with a low complication rate and whether it reliability relieves pain in patients with cervical spine metastasis.
We therefore evaluated (1) the technical feasibility considering the complications rate; and (2) the ability of PVP to reduce pain and medication usage in cervical fractures due to metastases.