Adverse jaw outcomes from immune checkpoint inhibitors for head-and-neck cancer? Case reports.

Abstract

Radiation treatment plays a mainstream role in the management of head and neck cancers (HNSCC). Adverse effects from radiation therapy include osteoradionecrosis of the jaw, and rarely, pathological fracture. Immune checkpoint inhibitors (ICI) such as pembrolizumab are of growing relevance to the management of metastatic and recurrent HNSCC. Adverse impact on bone secondary to medications such as pembrolizumab and nivolumab have been sporadically documented in the literature. The objective of this manuscript is to raise awareness of possible increase in risk for adverse jaw outcomes in patients with HNSCC exposed to both radiation treatment to the jaws and ICI therapy. This manuscript documents adverse jaw outcomes including osteonecrosis and pathological fracture of the mandible in two patients receiving pembrolizumab for management of HNSCC and had received prior radiation treatment. A potential link between immunotherapy and adverse jaw outcomes is consistent with our growing understanding of osteoimmunology, investigating the closely interrelated processes in bone remodeling and immune system function, in health and disease. It is important to ascertain if pembrolizumab poses an incremental risk for such outcomes, beyond the risk from prior radiation, for patients managed with radiation treatment and ICI therapy for HNSCC. The general dentist may encounter such patients either in the context of facilitating dental clearance prior to initiation of chemotherapy, or rarely, with poorly explained jaw symptoms and must be alert to the possibility of occurrence of such adverse jaw events to facilitate timely diagnosis and optimal patient management.