RESUMEN
BACKGROUND: Orbital apex syndrome (OAS) is a complex and uncommon disorder that typically damages multiple cranial nerves in association with optic nerve dysfunction. OAS is associated with several different pathologies, however; only a few cases have been reported in association with head and neck cancer (HNC) so far. MATERIAL AND METHODS: A case series of HNC patients diagnosed with OAS is described including clinicopathological data, image findings, and disease outcome. RESULTS: Ptosis and diplopia were diagnosed in four male patients with mean age of 61.2 years who were undergoing treatment for late-stage carcinomas of the tongue, larynx, and nasopharynx, eventually leading to the diagnosis of OAS. The mean overall survival rate after the diagnosis of OAS was 9.5 months. CONCLUSIONS: The current study reinforces evidence that OAS indicates poor prognosis and highlights the importance of early diagnosis.