Unexpected massive bleeding caused by extensive maxillary osteonecrosis in a breast cancer patient: a case report.

Diphosphonate application is routinely recommended to treat bone metastasis (BM) in cancer patients. However, the severe side effects of diphosphonate, especially after long-term use, are often overlooked by clinicians. In this article, we describe a case in which a heavily-treated breast cancer patient, suffered from massive bleeding as a result of maxillary osteonecrosis by zoledronic acid (ZA) and apatinib. In October 2018, a 48-year-old Chinese female with breast cancer presented at our department with brain metastases. The patient had experienced progression multiple times and had received several lines of systemic interventions. ZA was administered monthly for a rather long period of 37 months. She also took 250 mg of apatinib, a small molecular tyrosine kinase inhibitor (TKI) that targets vascular endothelial growth factor receptor 2, daily for 11 days. However, massive bleeding from the oral and nasal cavity occurred that could not be alleviated by conventional means. Computed tomography revealed severe destruction and loss of the right maxillary bone and maxillary sinus wall. A pathological examination of the exfoliated bone tissue further confirmed that the patient was suffering from necrosis rather than metastasis. An emergency interventional embolization was performed, and the bleeding was stopped. In this case, maxillary osteonecrosis developed from the antiresorptive agents. Antiangiogenesis drugs should be avoided whenever possible. In clinical practice, the high risk of osteonecrosis needs to be carefully considered. Further, care needs to be taken to ensure osteonecrosis is not misdiagnosed as BM, especially in stage IV patients. Pathology is a prerequisite for the timely and correct diagnosis and management. Life-threatening toxicity such as massive bleeding, should be avoided to ensure that patients receive adequate antitumor treatments.