Skull base or cervical vertebral osteomyelitis following chemoradiotherapy for pharyngeal carcinoma: A serious but treatable complication.

Osteomyelitis, infection of the bone and marrow, following high dose (chemo-)radiotherapy for head and neck cancer is uncommon and rarely seen in the cervical spine or temporal bone. Due to its proximity to critical structures, osteomyelitis in the latter regions could carry potentially important consequences. Furthermore, involvement near the skull base (e.g. temporal bone and high cervical vertebrae) presents unique challenges in diagnosis (especially in the differentiation from disease recurrence) and treatment, making early detection and timely intervention critical. In this report, we describe two cases of osteomyelitis, one involving the temporal bone and the other affecting the 2nd and 3rd cervical vertebrae, diagnosed and treated with good outcome in the setting of definitive chemoradiotherapy for locally advanced pharyngeal carcinomas. We suggest that for new or evolving post-radiotherapy osseous changes in regions that have received a high dose of radiotherapy, associated with unexpected and deteriorating spinal symptoms such as pain and spasm, radiation-related osteomyelitis should be considered in the differential diagnosis from tumor progression. Timely referral to a surgical oncologist and infectious diseases specialist is paramount in achieving satisfactory clinical outcomes.