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Bone destruction is a major feature of multiple myeloma with about 75% of patients exhibiting some form of bone abnormalities including areas of bone destruction (osteolytic lesions seen on X-rays), osteopenia (decreased bone density), osteoporosis, and pathologic fractures (fractures developing at a site that is weakened by a pre-existing condition such as osteoporosis).

Treatments for Myeloma Bone Disease:

• Radiation Therapy - to relive pain and/or to promote bone healing in patients with pathologic fractures.

• Percutaneous Vertebroplasty and Kyphoplasty - injection of polymethylmethacrylate (PMMA) bone cement into the vertebral body to relieve pain and restore the normal height of the vertebrae.

• Orthopedic Surgery - may be necessary in select cases for:

  • prevention of an impending pathologic fracture
  • treatment of an existing pathologic fracture
  • treatment of spinal instability or spinal cord compression

• Bisphosphonates - This is a class of synthetic drugs that inhibit the activity of specialized bone cells called osteoclasts that are involved in bone resorption. Increased osteoclastic activity is thought to be responsible for the bone destruction that often occurs in patients with multiple myeloma. The bisphosphonates have been widely used in the past for the treatment of osteoporosis as a means of preventing pathologic fractures. More recently, these drugs have also been used to treat patients with myeloma bone disease. A variety of bisphosphonates are available, however, of these, pamidronate is the standard drug used for the treatment of myeloma bone disease.

A major study published in 1996 in the New England Journal of Medicine (Vol. 334, pp. 488-493) involving 600 patients with multiple myeloma demonstrated that patients who were treated with pamidronate, as compared to a placebo:

• Had significantly less pathologic fractures
• Required fewer other interventions for myeloma bone disease such as radiation therapy or surgery
• Experienced less bone pain
• Had improved overall quality of life

More recently, another biphosphonate medication called zoledronic acid (Zometa) has been shown to be as effective as pamidronate for reducing skeletal (bone) complications in patients with multiple myeloma.

On September 24, 2004, the U.S. Food and Drug Administration (FDA) and Novartis notified healthcare professionals of revisions in the PRECAUTIONS and ADVERSE REACTIONS sections of labeling, describing spontaneous reports of osteonecrosis of the jaw mainly in cancer patients, who have received bisphosphonates as a component of their therapy. A dental examination with appropriate preventive dentistry should be considered prior to treatment with bisphosphonates in patients with concomitant risk factors (e.g. cancer, chemotherapy, corticosteroids, poor oral hygiene).