Bisphosphonate-related osteonecrosis: genetic and acquired risk factors

The objectives of this study were to review epidemiological, clinical and biological aspects associated with the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ) in multiple myeloma (MM) patients, with special emphasis on the genetic aspects. A detailed review of previously described risk factors as well as recent genetic findings mostly comprises this work. The most recent meeting abstracts and relevant articles published in journals covered by the Science Citation Index and Medline are also examined. The review pays special attention to the genetic component of BRONJ. A total of 15 series and 14 guidelines or revisions were selected to fit the aims of the review. Gene variability was reviewed in depth to give a clinical illustration on the genetic aspects of BRONJ. Crude prevalence and 5-year cumulative incidence were considered as the most important end points for predictive purposes. Several acquired factors were recognized as predictors for BRONJ in MM, especially intravenous bisphosphonates, dental trauma and advanced age. Among genetic factors, polymorphisms on CYP2C8 gene arise as a promising risk factor. Bisphosphonate-related osteonecrosis of the jaw can be predicted with a conjunction of genetic and environmental risk factors.