A retrospective study evaluating frequency and risk factors of osteonecrosis of the jaw in 576 cancer patients receiving intravenous bisphosphonates

To evaluate the frequency, risk factors, and clinical presentation of bisphosphonate (BP)-related osteonecrosis of the jaw (BRONJ). We performed a retrospective analysis of 576 patients with cancer treated with intravenous pamidronate and/or zoledronate between January, 2003 and December, 2007 at the University of Minnesota Masonic Cancer Center and Park Nicollet Institute. Eighteen of 576 identified patients (3.1%) developed BRONJ including 8 of 190 patients (4.2%) with breast cancer, 6 of 83 patients (7.2%) with multiple myeloma, 2 of 84 patients (2.4%) with prostate cancer, 1 of 76 patients (1.3%) with lung cancer, 1 of 52 patients (1.9%) with renal cell carcinoma, and in none of the 73 patients with other malignancies. Ten patients (59%) developed BRONJ after tooth extraction, whereas 7 (41%) developed it spontaneously (missing data for 1 patient). The mean number of BP infusions (38.1 ± 19.06 infusions vs. 10.5 ± 12.81 infusions; P