Results expression of ECD was always lower in poor differentiation group than that in well differentiation group, but there was no significant correlation between ECD expression and metastasis.

Low differentiated squamous cell carcinoma is about 80-85% of NPC pathological types and well differentiated squamous cell carcinoma is 10%.

The mucinous signet-ring cancer cells in high differentiation small cell adenocarcinoma should be differential diagnosis from mesothelium signet-ringoid change.