Bone scan manifestations of osteonecrosis of the jaw (ONJ) in cancer patients: Three unique clinical presentations

Learning Objectives 1. Discuss different clinical settings, other than biphosphonate use, that are associated with higher risk of ONJ. 2. Discuss how an early recognition of ONJ may lead to a proper medical management and help to minimize unnecessary biopsies and allow early treatment of ONJ.

Osteonecrosis of the jaw is usually a potential complication of bisphosphonate therapy. Our aim is to highlight clinical settings associated with a higher risk of ONJ to prevent possible misdiagnosis and initiate early treatment. We present 3 different cases of ONJ, each occurring in unique clinical setting of which 2 were misdiagnosed initially. First is a case with osteonecrosis of the mandible after multiple teeth extractions while on oral bisphosphonate therapy and was treated by discontinuation of the drug. Second is a case of breast cancer and multiple bone metastases on intravenous bisphosphonate therapy who underwent palliative radiation therapy for a presumed metastatic left mandibular angle lesion. Her jaw lesion and pain got progressively worse. A Tc99m bone scan and CT scan done suggested ONJ. Third is a case with osteonecrosis of the mandible that occurred after multiple teeth extractions. The patient underwent incision and drainage for a presumed massetric space infection. When her pain did not improve a Gallium-67 scan was obtained which showed no evidence of infection or inflammation but rather ONJ. Conclusions: Correlating a patient’s clinical information with findings on diagnostic imaging studies, such as SPECT bone and CT scans can help identify this potential complication. Early diagnosis helps minimize unnecessary biopsies and allows for the proper treatment to be instituted