1.The incorrect diagnosis ratio: 11.22%, less than our retrospective analysis; 31.25% and other reported analysis: 28.08-35%. 2.Overcoming used methods: endoscopic examination and biopsy; DNA extraction from tumor sample and PCR-EBV with primer EBNA2A, additionally by Dot Blot hybridization in accordance with ECL protocol and technique (Amersham RPN-3000). Obtained results of investigated 31 NPC patients showed that: 27/28 case with Undifferentiated carcinoma Nasopharyngeal Type (UCNT): (96.43%) are in conformity with histology, of which 2/27 cases (7.40%) are positive before histological diagnosis (6 months and 9 months). 1/28 cases (3.75%) are not in conformity with histology. In all 3 cases with Spinocellular carcinoma (S.C): (100%) the DNA-EBV is negative in tumor samples.
Nasopharyngeal Neoplasms ; Endoscopy