skull bone
2.RESULTS: Of 259 patients, 218 had nodal involvements. The nodal distributions, according to Som suggested nodal classification, were 0 inⅠA, 6 inⅠB, 136 in ⅡA, 171 in ⅡB, 78 in Ⅲ, 20 in Ⅳ, 60 in V, 0 in Ⅵ and Ⅶ, 5 in supraclavicle, 102 in retropharynx, respectively. Another 55 cases had lesions medial to the border of internal carotid artery, 2 cm from inferior to the skull base to the hyoid bone.

