A group of leading myeloma specialists, known as the International Myeloma Working Group, recently collaborated to develop guidelines for the proper management of bone disease in multiple myeloma. The group recommended that patients with bone disease should be treated with standard dosages of intravenous bisphosphonates. A minimally invasive procedure called kyphoplasty may also be considered to reduce bone pain and improve functional ability.

Dr. David Roodman of the University of Pittsburgh presented these findings at the International Myeloma Workshop (IMW) on May 6 in Paris.

Most multiple myeloma patients develop bone disease, which can cause bone fractures that are extremely painful and debilitating. The current gold standard for treating myeloma bone disease is bisphosphonates, a class of drugs that slow the breakdown of bone, thereby reducing the number of fractures.

Patients diagnosed with either smoldering myeloma or monoclonal gammopathy of undetermined significance, which are both asymptomatic diseases that can progress to myeloma, may also experience bone complications. According to Dr. Roodman, it is unclear whether these patients should be treated with bisphosphonates.  For now, the guidelines recommend that patients with these conditions should only use bisphosphonates if diagnosed with osteoporosis from a DEXA scan, which measures bone density and strength. However, all patients with high-risk smoldering myeloma and bone loss should consider bisphosphonate treatment.

Solitary plasmacytoma is another precursor disease in which the patient has a single mass of myeloma cells that often result in a bone lesion.  The guidelines do not recommend bisphosphonate treatment for this type of patient.

For myeloma patients with multiple lesions, the guidelines recommend treatment with a bisphosphonate.  For myeloma patients without evidence of bone disease, it is unclear whether they should be treated with bisphosphonates. Some research has shown bisphosphonate use may have a clinical benefit even in patients without bone disease.

Some bisphosphonates are administered orally, while others are administered through intravenous injections. The guidelines recommended that patients use intravenous bisphosphonates, such as Zometa (zoledronic acid), due to results from a recent clinical trial that suggested this bisphosphonate may extend survival. In addition, they recommended that physicians administer standard doses of bisphosphonates every three to four weeks.

It is still unclear how long bisphosphonates should be used.  There is currently no randomized data on bisphosphonate use for more than two years. As a result, physicians should assess a patient’s risk and benefit of using bisphosphonate treatment after two years.

For instance, researchers have speculated that long-term use of bisphosphonates increases one’s risk of developing osteonecrosis of the jaw, a rare but serious side effect of bisphosphonate use in which there is a loss of blood supply to the jaw, causing jawbone tissue to die. To prevent osteonecrosis of the jaw, patients treated with bisphosphonates should maintain good dental hygiene and should stop bisphosphonate treatment for 90 days before and after invasive dental procedures.

Rare fractures of the upper leg and in the feet have also been reported after long-term use of bisphosphonates.

The guidelines also recommend that myeloma patients make sure to get enough vitamin D and calcium, nutrients essential for strong and healthy bones.  This is a concern because sixty percent of myeloma patients are vitamin D and calcium deficient. The guidelines say that patients may use vitamin D and calcium supplements with bisphosphonate treatment, but calcium supplementation should be used cautiously for patients with kidney problems.

Minimally invasive surgery can also be used to reduce pain associated with a spinal compression fracture and to improve a patient’s functional ability. In particular, the guidelines recommended kyphoplasty, a procedure in which a physician inserts and inflates a small balloon into the fractured vertebra, creating a space that is then filled with an acrylic cement to stabilize the spinal cord. However, there is conflicting evidence as to the benefits of vertebroplasty, a procedure in which the cement is injected directly into the fractured vertebra.

Radiation therapy may also be used for pain reduction and localized improvements in function. However, it should only be used in urgent cases, depending on a patient’s prior treatment history and response, due to its impact on bone marrow function.

For more information, please see the full guidelines (pdf), which are available on the IMW website.