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Cancer and Bone Pain Dealing with the severe bone pain that can accompany bone metastases

How does cancer cause bone pain?

The form of cancer known as Bone metastases can cause bone pain (2). The pain can be caused by the metastasis stretching the cover of the bone (the periosteum), by the metastasis pressing on a nerve root, or by chemicals that the metastasis secretes into the area around it (1). In addition, the metastasis can press on muscles, causing reflex muscle spasm that pulls on the bone and can cause pain (1). Bone pain is often not just felt in the area of the bone metastasis (1). Cancer-related bone pain may have an aching quality or may burn with episodes of stabbing pain (1).

Treating cancer-related bone pain directly

Bone pain should be treated with appropriate analgesics (pain medication) (5). However, more can be done to reduce the pain.

Cancer-related bone pain can be treated directly by targeting the metastasis alone or by treating the tumor and all its metastases. A common direct treatment for bone pain is radiation (1). Local radiation is used for single sites of pain (1). When there are multiple, scattered, and painful sites, wide field radiation is used (1). Another type of direct treatment involves using chemicals given by mouth or intravenously (in a vein) to prevent all the tumor cells from reproducing (1). This is called systemic therapy (1). Systemic therapy to shrink the mass of tumor throughout the body reduces the amount of chemicals that the tumor secretes, decreasing the stimulation of osteoclasts and the breakdown of bone (1). The systemic therapy chosen depends on the tumor type (1). Systemic therapy can be chemotherapy (medications designed to treat the cancer), endocrine therapy (using hormones to treat the cancer), or bone-seeking isotope radiation therapy (injection of radioactive chemicals that specifically target bone metastases) (1).

Treating cancer-related bone pain indirectly

Indirect therapy for cancer-related bone pain uses systemic therapy to block the effects of the chemicals secreted by the tumor (1). Indirect therapies prevent the normal cells, especially the osteoclasts, from responding to the tumor products. Bisphosphonates are synthetic (man-made) compounds similar to a naturally occurring chemical that is part of normal bone (3). Bisphosphonates bind strongly to bone (3). They are more resistant than the natural chemical to being broken apart by osteoclasts, so they prevent the osteoclasts from breaking down bone (3). They are the most widely used indirect therapy for cancer-related bone pain (4). Another indirect treatment is a hormone that is normally secreted in the body, called calcitonin (4). Normally, calcitonin decreases the reabsorption of calcium from bone; calcitonin therapy gives extra calcitonin to combat bone breakdown (4). Unfortunately, with time, the effects of extra calcitonin decrease, so this is a secondary therapy (4)

Surgery

Finally, surgery may be necessary (1). Ten percent of patients with spinal bone pain have spinal instability that requires surgery to stabilize the bone in order to relieve the pain (1).

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