Osteonecrosis of the jaw (ONJ) in cancer patients treated with Bisphosphonates: how the knowledge of a phenomenon can change its evolution

Abstract

Osteonecrosis of the jaw (ONJ) is a severe complication of bisphosphonates treatment. Bisphosphonates reduce skeletal adverse events and give a clinical benefit to cancer patients. Therefore, it is necessary to identify appropriate procedures to reduce ONJ injures by using a successful monitoring program. In a retrospective study we analyzed the impact of a prevention program based on clinical oral cavity examination, dentists, and patients' education. The aim of the study was to evaluate if this approach might improve ONJ outcome in patients receiving pamidronate or zoledronate. We analyzed retrospectively two different groups of patients treated at our Institution: patients treated from October 2003 to June 2005 (group A) and patients treated from June 2005 to April 2007 (group B). In June 2005 the prevention program started for all our patients. One hundred and eighty-six cancer patients with bone involvement, treated with bisphosphonates, were considered. Sixteen of them developed ONJ: eight before and eight after June 2005. We observed a consistent difference in the evolution of the two groups. In the first group, four patients underwent a major surgery (one partial maxillectomy, complicated by septic shock and oronasal communication; two partial mandibulectomies; and one segmental mandibular resection), with an important impairment of their quality of life; while the eight new ONJ cases, diagnosed after June 2005, were successfully treated without aggressive dental interventions, and achieved a good control of symptoms. Bisphosphonates-related ONJ is a frequent adverse event (8.6%). The monitoring program proved very efficient to improve the clinical outcome of ONJ, avoiding an aggressive treatment and using a conservative approach and medical therapy.