Longitudinal cohort study of risk factors in cancer patients of bisphosphonate-related osteonecrosis of the jaw.

PURPOSE: The reported incidence of osteonecrosis of the jaw (ONJ) ranges from 0.94% to 18.6%. This cohort study aimed to calculate the incidence of and identify the risk factors for ONJ in patients with cancer treated with intravenous zoledronate, ibandronate, and pamidronate. PATIENTS AND METHODS: Data analyzed included age, sex, smoking status, underlying disease, medical and dental history, bisphosphonates (BP) type, and doses administered. Relative risks, crude and adjusted odds ratios (aORs), and cumulative hazard ratios for ONJ development were calculated. RESULTS: We included 1,621 patients who received 29,006 intravenous doses of BP, given monthly. Crude ONJ incidence was 8.5%, 3.1%, and 4.9% in patients with multiple myeloma, breast cancer, and prostate cancer, respectively. Patients with breast cancer demonstrated a reduced risk for ONJ development, which turned out to be nonsignificant after adjustment for other variables. Multivariate analysis demonstrated that use of dentures (aOR = 2.02; 95% CI, 1.03 to 3.96), history of dental extraction (aOR = 32.97; 95% CI, 18.02 to 60.31), having ever received zoledronate (aOR = 28.09; 95% CI, 5.74 to 137.43), and each zoledronate dose (aOR = 2.02; 95% CI, 1.15 to 3.56) were associated with increased risk for ONJ development. Smoking, periodontitis, and root canal treatment did not increase risk for ONJ in patients receiving BP. CONCLUSION: The conclusions of this study validated dental extractions and use of dentures as risk factors for ONJ development. Ibandronate and pamidronate at the dosages and frequency used in this study seem to exhibit a safer drug profile concerning ONJ complication; however, randomized controlled trials are needed to validate these results. Before initiation of a bisphosphonate, patients should have a comprehensive dental examination. Patients with a challenging dental situation should have dental care attended to before initiation of these drugs.

Bisphosphonate-related osteonecrosis of the jaws: a case-control study of risk factors in breast cancer patients.

PURPOSE: Osteonecrosis of the jaws (ONJ) was initially described in 2001 in patients receiving intravenous bisphosphonate (BP) treatment. The objective of the present study was to determine whether routine dental procedures can be considered as possible risk factors for the development of ONJ in breast cancer patients receiving BP. PATIENTS AND METHODS: Twenty breast cancer patients who developed ONJ receiving BP treatment were included in group A, whereas group B consisted of 40 matched controls (breast cancer patients who did not progress to ONJ receiving BP treatment). Routine dental care, smoking habits, history of tooth extraction, use of dentures, and root canal therapy were recorded. RESULTS: Our results indicate that history of tooth extraction during zoledronic acid treatment (adjusted odds ratio [OR] = 16.4; 95% CI, 3.4 to 79.6) and the use of dentures (adjusted OR = 4.9; 95% CI, 1.2 to 20.1) increase the risk of developing ONJ. CONCLUSION: The outcome of the present study suggests early referral by oncologists for dental evaluation for every patient to be treated with BP. These results raise the current American Society of Clinical Oncology Level of Evidence linking certain dental procedures with ONJ from V to III. Further studies are needed to assess other possible risk factors and also to highlight the etiopathogenesis mechanism of ONJ.

Incidence, risk factors and management of osteonecrosis of the jaw in patients with multiple myeloma: a single-centre experience in 303 patients.

The incidence, characteristics and risk factors for the development of osteonecrosis of the jaw (ONJ) were evaluated among 303 myeloma patients. Only patients who received bisphosphonates developed ONJ (28/254; 11%). Zoledronic acid produced 9.5-fold greater risk for developing ONJ than pamidronate alone (P = 0.042) and 4.5-fold greater risk than subsequent use of pamidronate + zoledronic acid (P = 0.018). Use of thalidomide and number of bisphosphonate infusions also increased the risk for ONJ by 2.4-fold (P = 0.043), and 4.9-fold respectively (P = 0.012). ONJ developed earlier among patients receiving zoledronic acid. Our data indicates that administration of zoledronic acid for more than 2 years or in combination with thalidomide requires caution in myeloma.