Longitudinal cohort study of skeletal-related events (SRE) and long-term prognosis in patients with multiple myeloma (MM) with bisphosphonate-related osteonecrosis of the jaw (ONJ).

e19645 Background: Nitrogen containing bisphosphonates (BIS) have been shown to decrease SRE and improve survival in patients with MM. BIS use has been tempered by the occurrence of ONJ. Little is known about the prognosis incidence of SRE in MM patients with ONJ. Could the development of ONJ be a biomarker of enhanced sensitivity to BIS, with reduced SRE and better survival? Methods: In this retrospective cohort study, 11 MM patients who met diagnostic criteria for ONJ between June 2005 and June 2010 were matched to 39 MM patients without ONJ from our institution’s database. Patients were matched based on age, stage, histology, gender, ethnicity, and performance status. Skeletal surveys were used to evaluate bone disease at the start of BIS infusions and during follow-up. SRE’s were defined as: a pathological fracture, surgery to treat pathological fractures, radiation to bone, spinal cord compression or hypercalcemia. SRE were recorded from start of BIS, events needed to be > 21 days apart to be counted...