Antiresorptive therapy in combination with radiation results in enhanced risk for necrosis and associated complications

Patients exposed to a combination of antiresorptive medication and radiotherapy of the head and neck area developing necrosis of the jaw in the course of treatment are extremely rare. Therefore, the aim of this study was to identify the outcome and complications in this highly vulnerable patient cohort. Seventeen patients who received both antiresorptive treatment and radiotherapy (medication-related osteonecrosis of the jaw/osteoradionecrosis = the [MRONJ/ORN] group) in the head and neck area were enrolled in this study. Included patients were treated in our department between 2005 and 2022. Four hundred twenty-four patients with MRONJ (the MRONJ group) and 138 patients with ORN of the jaw were enrolled as two control groups (the ORN group). Demographic data, lesion localization, date of primary diagnosis, clinical symptoms, type of therapy (surgical or non-surgical), details on antiresorptive treatment, outcome, and complications were recorded. Pathological fractures, continuity resection, and recurrence appear more often in patients who receive a combination of antiresorptive treatment and radiotherapy in the head and neck area compared with patients undergoing only one of these treatments. There was a statistically significant difference ( < .001) between the MRONJ/ORN group and the MRONJ group and the MRONJ/ORN group and the ORN group considering recurrence, fracture, and continuity resection. Patients with ORN combined with MRONJ have a 4-times higher risk for developing recurrence compared with patients with MRONJ and a 1.5-times higher risk for recurrence compared with patients with ORN. Jaw fracture and continuity resection appear more often in patients with MRONJ/ORN. Patients under antiresorptive therapy in combination with radiation therapy in the head and neck area have a higher risk for developing complications in case of osteonecrosis of the jaw. Therefore, a strict follow-up care schedule is highly recommended.