Abstract
Osteoradionecrosis is one of the late complications after radiation therapy for head and neck cancer. Osteoradionecrosis generally occurs in the mandible, but it can also occur in the skull base depending on the radiation field. Once it occurs in the skull base, it may cause serious complications such as cranial nerve disorders, intracranial infection and carotid rupture due to the anatomical features of the skull base. Here, we report three cases of skull base osteoradionecrosis.
Case 1 was a 55-year-old man, who received CyberKnife treatment for nasopharyngeal cancer. Four months after the initial treatment, local recurrence was confirmed and he selected re-irradiation using CyberKnife after understanding the risk of bone necrosis. Since FDG accumulation in the nasopharynx appeared in FDG-PET 5 months after re-irradiation, a biopsy was performed but it indicated no evidence of malignancy. Then, long-term administration of antibiotics was given for skull base osteoradionecrosis in accordance with skull base osteomyelitis.
Case 2 was a 78-year-old man, who received intensity modulated radiation therapy for nasopharyngeal cancer. Eight months after the treatment, necrotic tissue was seen in the nasopharynx and he suffered from headache. It was strongly suspected to be due to skull base osteoradionecrosis. His condition was stabilized by long-term administration of antibiotics.
Case 3 was a 55-year-old man, who received chemo-radiotherapy for sinonasal cancer. Six months after the treatment, endoscopic findings showed bone necrosis in sphenoidal bone and he suffered from headache. His condition was stabilized once after administration of antibiotics, however, he died due to carotid rupture 12 months later.
Early diagnosis and long-term administration of antibiotics are essential for the management of skull base osteoradionecrosis in accordance with that of osteomyelitis. Clinicians must obtain enough informed consent from patients and their family, including the possibility of sudden death due to carotid rupture.
