Multiple myeloma vs. breast cancer patients with bisphosphonates-related osteonecrosis of the jaws: a comparative analysis of response to treatment and predictors of outcome

Multiple myeloma (MM) and breast cancer (BC) are the two most common diseases associated with bisphosphonates-related osteonecrosis of the jaws (BRONJ), for which different therapeutical approaches have been proposed. The aim of this study was to compare the clinical behaviour of BRONJ in patients with MM vs. BC and the time of healing in terms of clinical and symptomatological remission, following a standardized therapeutic protocol. METHODS:Twenty-six BRONJ patients (13 men with MM and 13 women with BC) were prospectively enroled and treated with a specific systemic and topical antibiotic therapy. Several predictors of outcome were also evaluated. RESULTS:Nine patients (69.2%) with BC and 10 patients (76.9%) with MM progressed towards a complete clinical remission (CR) in a mean healing time of 183.3 days [SD: 113.7; 95% confidence interval (CI): 95.95-207.7] and 372.0 days (SD: 308.0; 95% CI: 151.7-592.3) (P = 0.776), respectively. The clinical improvement was statistically significant (P = 0.0013 and P = 0.0014), as well as the assessment of pain (P = 0.0015 and P = 0.0015), in MM and BC group, respectively. Cox regression analysis revealed that just triggering events (P = 0.036) were found to be significant predictors of outcome of BRONJ healing. CONCLUSIONS:Both groups of cancer patients experienced clinical and symptomatological remission regardless their malignancy, but BC patients earlier than MM patients.