Table 3.

The pathways of local recurrences of nasopharyngeal carcinoma

Pathways	Details of each pathway	Count	Percentage (%)
Lateral tumor extension	Nasopharynx-LVPM-Pharyngobasilar fascia-TVPM-Medial pterygoid muscle & Parapharyngeal space-Foramen ovale-Cavernous sinus; or Nasopharynx-LVPM- Pharyngobasilar fascia-Jugular foramen	8	15.4
Superior tumor extension	Nasopharynx-Bottom of sphenoid sinus- Sphenoid sinus; or Nasopharynx-Clivus & Foramen lacerum -Cavernous sinus	10	19.2
Anterior tumor extension	Nasopharynx-Posterior Nasal Cavity-Pterygopalatine fossa-Foramen rotundum & Inferior orbital fissure- Cavernous sinus & Orbit; or Nasopharynx-Posterior Nasal Cavity-Posterior ethmoid sinus-Anterior ethmoid sinus	16	30.8
Posterior tumor extension	Nasopharynx-Prevertebral muscle- Clivus & Hypoglossal canal	7	13.5
Caudal tumor extension	Nasopharynx-oropharynx	3	5.8

LVPM, Levator veli palatine muscle; TVPM, Tensor veli palatine muscle