Bisphosphonate-associated osteonecrosis of the auditory canal

Denosumab-related osteonecrosis of the external auditory canal-benefit of the early surgical management

Background: Antiresorptive drugs are widely used to reduce bone mineral loss in patients with osteoporosis and to prevent skeletal-related events in patients with metastatic cancers and multiple myeloma (MM). Both the bisphosphonates (BP) and denosumab typically used in this indication were shown to be effective and relatively safe. Obviously, this medication could have some adverse effects; one of them is osteonecrosis of the external auditory canal. Only sporadic cases of external auditory canal osteonecrosis have been published yet. Here, we provide a case of denosumab-related osteonecrosis of the external auditory canal successfully treated surgically in the early stage of the disease. Case report: A 68-year-old patient with breast cancer underwent comprehensive oncological treatment, including denosumab administration. She was diagnosed with osteonecroses in the jaw and ear canal. The necrotic bones in both regions were resected with primary wound closure. Both affected sites healed well with no signs of necrosis recurrence. Conclusions: Osteonecrosis of the external auditory canal is a rare but probably underdiagnosed complication of antiresorptive medication. It has a negative impact on patient quality of life if left untreated. Early surgical treatment appears to be effective. The authors highlight several similarities with medication-related osteonecrosis of the jaw. Therefore, an analogous disease staging and treatment rationale is suggested.

Medication-related osteonecrosis of the external auditory canal - A rapid review of the literature and relevance to special care dentists

AIMS

There is growing evidence that anti-resorptive and anti-angiogenic medications can cause medication-related osteonecrosis of the external auditory canal (MROEAC). It is possible that patients taking risk medications may also suffer from concomitant medication -related osteonecrosis of the jaw (MRONJ) or temporomandibular joint (TMJ) involvement. The aim of this paper is to conduct a rapid review of the literature on MROEAC, and, its relevance to special care dentists.

METHODS AND RESULTS

A rapid review of the literature was carried out using PubMed, Science Direct and Google Scholar to identify papers relating to MROEAC. The grey literature and non-English papers were also consulted. Overall, 19 papers were identified from 2005 until December 2022.

CONCLUSIONS

Patients at risk of MRONJ may also be at risk of MROEAC and present to special care dentists. Dental/orofacial disease may cause signs and symptoms suggestive of MROEAC. It should be considered as a potential cause of orofacial pain in special care patients. MROEAC can have a significant impact on a patient's dental treatment, including access, the provision of sedation, communication difficulties, and consent issues.

Denosumab and bisphosphonate associated bilateral osteonecrosis of the external auditory canal

We present a case of non-surgically managed bilateral osteonecrosis of the external auditory canal with a history of long-term medical therapy for osteoporosis. A 79-year-old woman with severe osteoporosis and destructive osteoarthritis received >10 years of once weekly bisphosphonate therapy before switching to denosumab. Four months later, the patient presented with bilateral loss of hearing and right-sided otalgia. Necrotising otitis externa, cholesteatoma and malignancy were considered but with histology, microbiological and CT assessment, bilateral osteonecrosis of the external auditory canal was diagnosed. Surgical debridement with canalplasty was avoided due to our patient's comorbidities. Treatment continued for 5 months with regular aural toilet, Terra-Cortril ointment and bismuth-iodine-paraffin paste packing. At 1-year follow-up, bilateral external auditory canals were completely re-epithelialised with no pain or affected hearing. We report the first case of bilateral osteonecrosis of the external auditory canal associated with denosumab and bisphosphonates with successful conservative management.

Infection as an Important Factor in Medication-Related Osteonecrosis of the Jaw (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) has become a well-known side effect of antiresorptive, and antiangiogenic drugs commonly used in cancer management. Despite a considerable amount of literature addressing MRONJ, it is still widely accepted that the underlying pathomechanism of MRONJ is unclear. However, several clinical and preclinical studies indicate that infection seems to have a major role in the pathogenesis of MRONJ. Although there is no conclusive evidence for the infection hypothesis yet, available data have shown a robust association between local infection and MRONJ development. This observation is very critical in order to implement policies to reduce the risk of MRONJ in patients under antiresorptive drugs. This critical review was conducted to collect the most reliable evidence regarding the link between local infection and MRONJ pathogenesis.

Sinusitis and oroantral fistula in patients with bisphosphonate-associated necrosis of the maxilla

Background

The management of bisphosphonate related necrosis of the jaw has become clinical routine. While approximately two thirds of the lesions are in the mandible, one third is located in the maxilla. In 40–50 % of maxillary necrosis the maxillary sinus is involved, leading to maxillary sinusitis and oro-antral communications.

Methods

This retrospective single center study includes all patients with diagnosis of BP-ONJ of the maxilla and concomitant maxillary sinusitis. The information collected includes age, gender, primary disease, bisphosphonate intake, involving type of bisphosphonate, route of administration and duration of BP treatment previous to surgical treatment and treatment outcome.

Results

A total of 12 patients fulfill the criteria of the diagnosis of maxillary sinusitis associated to maxillary necrosis, of which 6 Patients showed purulent sinusitis. All patients underwent surgical treatment with complete resection of the affected bone and a multilayer wound closure. A recurrence appeared in one patient with open bone and no sign of sinusitis and was treated conservatively.

Conclusions

Purulent maxillary Sinusitis is a common complication of bisphosphonate-related necrosis of the maxilla. The surgical technique described can be suggested for the treatment of these patients.

Diagnosis and management of osteonecrosis of the jaw: a systematic review and international consensus

This work provides a systematic review of the literature from January 2003 to April 2014 pertaining to the incidence, pathophysiology, diagnosis, and treatment of osteonecrosis of the jaw (ONJ), and offers recommendations for its management based on multidisciplinary international consensus. ONJ is associated with oncology-dose parenteral antiresorptive therapy of bisphosphonates (BP) and denosumab (Dmab). The incidence of ONJ is greatest in the oncology patient population (1% to 15%), where high doses of these medications are used at frequent intervals. In the osteoporosis patient population, the incidence of ONJ is estimated at 0.001% to 0.01%, marginally higher than the incidence in the general population (<0.001%). New insights into the pathophysiology of ONJ include antiresorptive effects of BPs and Dmab, effects of BPs on gamma delta T-cells and on monocyte and macrophage function, as well as the role of local bacterial infection, inflammation, and necrosis. Advances in imaging include the use of cone beam computerized tomography assessing cortical and cancellous architecture with lower radiation exposure, magnetic resonance imaging, bone scanning, and positron emission tomography, although plain films often suffice. Other risk factors for ONJ include glucocorticoid use, maxillary or mandibular bone surgery, poor oral hygiene, chronic inflammation, diabetes mellitus, ill-fitting dentures, as well as other drugs, including antiangiogenic agents. Prevention strategies for ONJ include elimination or stabilization of oral disease prior to initiation of antiresorptive agents, as well as maintenance of good oral hygiene. In those patients at high risk for the development of ONJ, including cancer patients receiving high-dose BP or Dmab therapy, consideration should be given to withholding antiresorptive therapy following extensive oral surgery until the surgical site heals with mature mucosal coverage. Management of ONJ is based on the stage of the disease, size of the lesions, and the presence of contributing drug therapy and comorbidity. Conservative therapy includes topical antibiotic oral rinses and systemic antibiotic therapy. Localized surgical debridement is indicated in advanced nonresponsive disease and has been successful. Early data have suggested enhanced osseous wound healing with teriparatide in those without contraindications for its use. Experimental therapy includes bone marrow stem cell intralesional transplantation, low-level laser therapy, local platelet-derived growth factor application, hyperbaric oxygen, and tissue grafting.