Intraosseous Squamous Cell Carcinoma Associated with Denosumab-Induced Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ) has been associated with the use of different drugs administered in the treatment of malignant neoplasms or metastases and in antiresorptive therapies. Since 2010, denosumab, a monoclonal antibody whose mechanism of action is to prevent the activation of the RANK receptor on the surface of osteoclasts, has been associated with osteonecrosis of the jaw. Primary intraosseous squamous cell carcinoma (PIOSCC) is a rare neoplasm characterised by the presence of squamous cells within the maxillary or mandibular bone without an initial clinical association with the oral mucosa. We present a case of a PIOSCC in an osteonecrosis of the jaw related to a patient who received antiresorptive treatment with denosumab outlining the clinical and histopathological features of MRONJ and PIOSCC.