Multiple Myeloma

Multiple myeloma is a cancer that affects a certain type of blood cell, called the plasma cell. Plasma cells live in the bone marrow, where they produce and release antibodies that fight germs and disease. When a plasma cell grows out of control, it can produce a tumor. These tumor cells are unable to help the body fight infections. In multiple myeloma, plasma tumors are spread throughout the bone marrow.

Multiple myeloma also affects bone health. Bone undergoes a constant remodeling process. Cells, called osteoblasts, make bone. And cells, called osteoclasts, dissolve bone. Multiple myeloma cells produce a substance that causes the osteoclasts to work harder, causing bone to dissolve faster than it is rebuilt. The bones become weak and are susceptible to fracture.

Multiple myeloma is an uncommon form of cancer. This year, the American Cancer Society estimates 16,570 new cases will be diagnosed in the U.S. About 13,310 Americans will die from the condition. About two-thirds of patients are over 65 at the time of diagnosis. For unknown reasons, multiple myeloma is twice as common in African-Americans as in whites.

Osteonecrosis of the Jaw

Osteonecrosis is a disease in which the blood supply to the bone is temporarily or permanently cut off. Bone is living tissue, and without blood, can die, leading to a collapse of the bone. Signs include jaw pain, swelling of the soft tissue, infection, drainage, loosening of the teeth and exposed bone.

Since 2000, health care professionals have reported more than 2,000 cases of osteonecrosis of the jaw in patients taking a class of medications, called bisphosphonates. These drugs inhibit the break down of bone by osteoclasts, helping bones to stay stronger. The medications are often prescribed for patients who are at risk for bone loss. (Research suggests more than 73 percent of patients with osteoporosis are taking bisphosphonates.)

The exact cause of jaw osteonecrosis in patients taking bisphosphonates is unknown. However, the condition appears to be linked to trauma associated with dental surgery, tooth extraction, poorly fitting dentures or oral infection. Some people theorize the drugs impair the ability of osteoclasts to remove diseased bone. The accumulation of diseased bone may interfere with the ability of osteoblasts to build new bone. The affected area of bone becomes very dense and new blood vessels may be unable to form, further inhibiting the natural healing process.

Risk for jaw osteonecrosis is highest among those using the IV form of bisphosphonates. According to the American Dental Association, when bisphosphonates are given intravenously, the drug goes right into the circulatory system and over 50 percent of the dose can be incorporated into the bone. Whereas, only about one percent of an oral dose is absorbed into the body.

Mansoor Madani, D.M.D., Oral and Maxillofacial Surgeon, has seen several cases of jaw osteonecrosis in his personal practice. He says discontinuing bisphosphonates doesn’t necessarily reduce the risk for jaw osteonecrosis because the damage to the bone may be permanent.

Madani says that although jaw osteonecrosis is still considered rare, there are no tests to determine who is at risk. He also cautions patients should not stop taking their medication without speaking to their physician. Patients can reduce their risk by having a thorough dental examination and correcting tooth or gum problems before starting bisphosphonate therapy. Patients should also inform their dentist if they are already taking bisphosphonates. Once bisphosphonates are started, patients must pay extra attention to good oral hygiene. Dental examinations are also recommended every three months.

Madani has developed a dental clearance form for patients to take to their dentist before starting treatment with Bisphosphonates. He has also developed a consent form for physicians to give to patients to open a discussion of the personal risks and benefits of the therapy.

Drug makers are paying attention to the problem. Novartis, the maker of Aredia® and Zometa®, has issued an advisory to alert health professionals about the risks of osteonecrosis of the jaw. The company advises patients to have a thorough dental examination before starting bisphosphonate therapy. In addition, dentists are advised to avoid invasive dental procedures, when possible, while a patient is taking the medication.

Merck, the manufacturer of FOSAMAX®, FOSAMAX Plus D™, and Boniva®, has acknowledged receiving reports of jaw osteonecrosis associated with these drugs. The label for FOSAMAX, the most commonly prescribed oral bisphosphonate, has been revised to reflect precautions for osteonecrosis of the jaw. If you are concerned about your osteoporosis medication, speak with your health care provider and dental professional.

For information on bisphosphonates and jaw osteonecrosis:

Academy of General Dentistry

American Association of Oral and Maxillofacial Surgeons

American Dental Association

National Institute of Dental and Craniofacial Research

For general information on osteoporosis or bone loss:

National Osteoporosis Association

For information on Multiple Myeloma:

American Cancer Society

The International Multiple Myeloma Foundation