A recent article in the Annals of Oncology discusses how preventive measures can be taken to reduce the occurrence of osteonecrosis of the jaw (ONJ) in patients taking Zometa. Zometa ^[1] (zolendronic acid) is a common bisphosphonate (BP) therapy given to treat bone damage due to myeloma, but like other BPs, the medication causes an unwanted side-effect, ONJ.

ONJ occurs when there is a loss of blood supply to the jaw, eventually causing jawbone death. In this study, patients were diagnosed with ONJ if there was exposed bone in the mouth six weeks after adequate treatment, pain and discharge in the mouth, and no earlier radiotherapy treatment.

In this study, patients underwent a full dental work-up before beginning treatment with Zometa. Dentists checked for infections, if tooth extractions were needed, and made sure dentures fit correctly. Any patient who needed such major procedures as tooth extractions were sent to a specialized dental surgeon. Dental surgery was kept to a minimum by using less invasive techniques. For example, instead of a whole tooth extraction, the root was preserved. Zometa was given after patients had fully healed from dental procedures, and while on therapy, patients practiced good oral hygiene. All patients in the study were educated on ONJ.

Zometa was given in four milligram doses over 15 minutes every four weeks. Treatment with Zometa was started six to eight weeks after dental work. In patients who developed ONJ, Zometa therapy was stopped and only reintroduced if the condition healed. Other therapies the patients were undergoing, including dexamethasone ^[2], thalidomide ^[3] (Thalomid), and Velcade ^[4] (bortezomib), were not changed.

The researchers compared two groups: group A had preventive dental measures done before Zometa treatment and group B had preventive dental measures done after Zometa treatment was initiated. There was nearly a three-fold decrease of ONJ resulting from Zometa treatment after preventive measures were taken. Additionally, ONJ developed 33.5 months after Zometa treatment in group A compared to only 29.5 months of Zometa treatment in group B. Out of the 128 total patients, only 12.5 percent developed ONJ.

Also, it was observed that three-month intervals of Zometa reduced the risk of developing ONJ when compared to monthly intervals.

Patients who take Zometa to treat bone damage resulting from multiple myeloma should be aware of the risks associated with this therapy and consult their doctors for information. Another study ^[5] mentioned earlier on the Beacon has shown that esophageal cancer is also a risk associated with BP therapy.

For more information on this study, see the full article in the Annals of Oncology ^[6].