Characterization of herpesvirus infection in cervico-vaginal samples

: role in cervical cancer

Abstract

Introduction: Cervical cancer is the third most common cancer in women worldwide. A persistent infection by high-risk HPV is considered the etiological agent necessary but not sufficient for its development. Several studies suggest an interaction of other pathogens, such as Epstein-Barr virus (EBV) and Cytomegalovirus (CMV).Aims of the study: The aim of this study was to establish a correlation between EBV and CMV infection in the development of cervical cancer by studying its prevalence in different lesions.Materials and Methods: This study was performed in 89 cervico-vaginal samples of women with different cervical lesions, who attended the Department of Gynecology at the Portuguese Institute of Oncology of Porto. The frequency of EBV and CMV infections was evaluated by real time PCR with specific probes for the viral genes.Results: Our study revealed a frequency of 10.1% women with EBV infection and 5.20% with CMV infection. The CMV DNA was detected on: normal (1.20%), low-grade lesion (8.20%), high-grade lesion (6.80%), in situ/invasive cervical carcinoma (13.3%); EBV infection was detected in all types of lesions: normal (16.7%), with inflammation (5.26%), low-grade lesion (9.52%), high-grade lesion (4.50%) and in situ/invasive cervical carcinoma (22.2%). Both CMV and EBV infection were present in all age groups, with no predominance in any of these. In risk analysis, only CMV infection revealed an increased risk for the development of low-grade lesions (OR=7.73, p=0.043) and all kinds of lesions plus in situ/invasive carcinoma (OR=7.73, p= 0.021). In the correlation between CMV/EBV and HPV infection no statistically significant results were obtained that would indicate an increased risk in the development of lesions.Conclusion: This study demonstrated a low prevalence for both viruses under study (EBV and CMV) relative to previous studies. The results showed: 1) ubiquitous distribution of CMV and EBV in women with different lesions; and 2) CMV infection should indicate an increased risk in the development of carcinoma in situ/invasive cervical carcinoma.

Date of Award	2012
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Hugo Manuel Lopes Sousa (Supervisor)