Epstein-Barr virus, human papillomavirus, and flow cytometric cell cycle kinetics in nasopharyngeal carcinoma and inverted papilloma among Egyptian patients

It is widely accepted that the Epstein-Barr virus is etiologically associat ed with the development of nasopharyngeal carcinoma. The human papillomavir us is also associated with inverted papilloma. We used the polymerase chain reaction technique to detect both viruses in both types of tumors. Flow cy tometry was also used to study the DNA pattern and proliferative behavior o f the tumors in relation to the viruses. EBV was detected in 13/20 (65%) of NPC specimens, and in none of IP (n = 10) or control specimens (n = 10). T his indicates the contribution of EBV as an etiologic factor in NPC. Five c ases of NPC (25%) were positive for HPV 16, two of them were EBV positive. Four HPV 16 positive cases were found among cases with inverted papilloma, but none among the control cases. Flow cytometry revealed that all NPC, IF, and control samples were diploid except one aneuploid NPC sample. Prolifer ative capacity (PC) of primary tumors was predictive of tumor recurrence in NPC. Using 13.6% as a cut-off point for PC, we were able to discriminate b etween high risk and low risk groups with 100% sensitivity and 86% specific ity. PC can be used as a baseline prognostic parameter in NPC, making it po ssible to modify courses of treatment in an attempt to inhibit tumor recurr ence.