Osteonecrosis of the Jaw in Multiple Myeloma Patients (the IFM Registry).

PURPOSE: to describe the incidence, characteristics and risk factors for osteonecrosis of the jaw (ONJ) in multiple myeloma (MM).

PATIENTS AND METHODS : retrospective review of 51 ONJ collected from the IFM centers. For MM, age at diagnosis, isotype, DS staging, nature of chemotherapy and number of Stem-Cell Transplantation were the same that expected.

RESULTS: ONJ occurred predominantly in the mandible (70%). The median time of exposure to biphosphonates (BP) was 45 months (4 to 144 months). BP therapy included: zoledronate (85%), pamidronate (10%), clodronate (5%), all of the patients have received intravenous BP before, two patients have no BP at the time of diagnosis of ONJ.

RISK FACTORS: dental extraction (59%) other dental care (5%), dental infection (24%), others (30%), no risk factor (10%). SYMPTOMS: pain (92%), purulent discharge (37%), presence of exposed bone (60%), fracture (2%).

MANAGEMENT: BP discontinuation (84%), medical treatment (86%), removal of sequestra (51%), extensive surgery (20%).

EVOLUTION: improvement (55%), chronical symptoms (70%).

INCIDENCE: we have not the number of exposed patients but: 46 centers/73 reported no ONJ.The first report was march 2001. In the same period, 1695 patients where included in IFM trials and only 16 ONJ where observed. Year of diagnosis: before 2004: 5 cases; 2004: 11 cases; 2005:26 cases; 2006: 7 cases; 2007(6 months): 2cases.

CONCLUSION: ONJ is an adverse side effect of amino BP therapy (zoledronate>pamidronate), is time dependant and often after dental extraction. Preventive recommandations applied in 2005 can explain the decreasing incidence of ONJ in our study.