At the recent twelfth annual International Myeloma Workshop (IMW), physicians discussed strategies for managing multiple myeloma symptoms. Their topics included deep vein thrombosis (DVT), a potentially fatal blood clot in the body's large veins, and myeloma-induced bone disease, including "soft spots" and fractures.

DVT involves blood clot formation in the deep veins of the body, and if a clot dislodges, it may travel to other areas and block blood flow to vital organs. Researchers estimate that approximately 70 percent of all critical blockages of lung blood vessels originate from DVT in the pelvis or lower extremities.

Multiple myeloma patients face a higher risk of DVT, both because of molecular abnormalities intrinsic to myeloma and because of side effects from the newer class of treatment agents. In the era before these drugs emerged, approximately two to three percent of elderly myeloma patients experienced DVT during treatment. This risk, albeit higher than that in the general population, nevertheless remained low enough that broadscale clot-preventative measures were unwarranted.

With the advent of new immunomodulatory agents, including Revlimid (lenalidomide), Velcade (bortezomib), and thalidomide (Thalomid), DVT incidence has risen to between 10 percent and 30 percent. For many myeloma patients, guidelines now advocate daily aspirin intake, which acts as a blood thinner and helps to prevent clots. Patients with a higher DVT risk, including those who are immobilized or are overweight or diabetic, should usually receive a prescription blood thinner.

These preventative measures have greatly reduced the incidence of DVT, allowing patients to continue more safely with their treatment regimens. As Dr. Sundar Jagannath explains, "Nowadays we can mitigate or prevent the occurrence of blood clot and still the patient can benefit from a life-saving drug."

In addition to DVT, multiple myeloma patients may also experience bone disease and its complications. Specifically, many patients develop soft spots where the myeloma has damaged bone structure, which causes pain and increases fracture risk. Guidelines suggest treating patients for a year with bisphosphonates, such as Aredia (pamidronate) or Zometa (zoledronic acid), which help inhibit bone breakdown. Individuals in remission may discontinue this bone therapy but resume it if their cancer returns.

Presently, the available bone treatments can only inhibit further bone deterioration, rather than stimulate bone regrowth. Promising drugs on the horizon, however, may actually restore weakened bone areas.

Already, evidence suggests that Velcade, a drug for directly treating multiple myeloma, may also function to restore bone loss; in this regard, the drug simultaneously fights the bone disease and the underlying cancer. New experimental drugs, including RANK ligand inhibitors and Wnt signaling pathway drugs, have also proved encouraging for promoting bone regrowth. One RANK ligand inhibitor, Amgen's denosumab, is currently in the final stages of FDA review, and the company expects a decision on approval by October 2009.

Physicians may also perform surgery for myeloma patients experiencing acute spinal pain from compressed vertebrae and fractures. The procedure, kyphoplasty, involves inserting a small balloon to separate compressed vertebrae and applying bone cement to stabilize the spinal column. Although not all patients are appropriate candidates, kyphoplasty can often restore lost height and, perhaps most importantly, provide instantaneous pain relief to the affected area. In contrast, non-invasive, localized radiation cannot immediately relieve spinal pain, because it functions through the slower process of destroying the underlying myeloma.

For more information, see the IMW presentation transcript (pdf) provided by the MMRF.