Consolidation of Tumorous Mandibular Ramus Defect During Denosumab Treatment for Rapidly Progressive Metastatic Breast Cancer

BACKGROUND: Pharmacological inhibition of osteoclast activity is an essential component of oncological therapy for patients with bone metastases. In rare cases, medication-related osteonecrosis of the jaws (MRONJ) is observed. MRONJ can cause bone defects not inferior to primary or metastatic jaw neoplasms. Oral examination of patients on osteoclast-inhibiting medication aims to identify risk factors at an early stage and to initiate therapy. The current focus on osteoclast-inhibiting drugs in the maxillofacial region is MRONJ. Effects of the substances other than MRONJ are rarely reported.

CASE REPORT: The female patient with metastatic breast cancer had developed extensive osteolysis of the mandibular ramus at the time of initial diagnosis. The patient was treated with denosumab. Seven months later, a significant reduction in the mandibular osteolytic zone was recorded. However, known bone metastases from other sites had increased in size during multimodal therapy, and further metastases were recorded.

CONCLUSION: Jaw metastasis can shrink under denosumab therapy.