Fig. 5

Associations between clinical stage and the proposed histopathologic classification in all NPC patients. The proportions of EC cases are 71.8%, 63.3%, 61.1%, and 60.4% in patients with stages I, II, III, and IV NPC (the 1992 China and 1997 AJCC staging systems combined), respectively, whereas those of SC cases are 9.6%, 11.8%, 13.7%, and 14.6%, respectively. The proportion of SC increased with advanced stage, whereas the proportion of EC decreased with more advanced stage (Chi square test, P = 0.001)