Cancer that spreads to the bones from another site is called metastases. The spine is a common place for metastases from certain kinds of cancer. Lung, breast, and thyroid cancer can spread to the cervical spine (neck). Colon and stomach cancer are more likely to metastasize to the lumbar spine.
Treatment decisions for cancer patients often do require a team of experts. Your oncologic status must be taken into consideration. What kind of primary cancer is present? Is the cancer in your spine really from the original cancer? Or do you have a second kind of tumor? This is important in looking at whether or not radiation or chemotherapy is the best approach.
The orthopedic surgeon will discuss the stability of your spine and what's needed there. Are the bones too brittle for screws? Would a fusion help? Usually, even a single level needs stabilization above and below to hold it in place. Further testing may be needed to see if the tumor is wrapped around important blood vessels.
The goals of treatment are to improve or maintain neurologic function. At the same time, they try to control tumor growth and give you pain relief. Stabilizing the spine with a neck fusion or other spine surgery may help. They may recommend further chemotherapy or radiation therapy either before or after surgery to stabilize your spine.
Your overall general health is part of the equation. Are you stable enough to have surgery or further cancer treatment if needed? There's actually a model proposed for use in such decision-making. It's called the NOMS framework. By taking each area (neurologic, oncologic, mechanical, systemic) into consideration, a plan of care can be determined.