Detection of Human Papillomavirus Genotypes in Cervical Intraepithelial Neoplasia and Invasive Cancer Patients: Sharkia Governorate, Egypt

Background: Cervical cancer (CCA) is the 2nd most common cancer among women worldwide. For approximately 2 years now, CCA has been converted from an oncological disease to an infectious disease, almost certainly caused by Human papillomavirus (HPV). Development of effective vaccines against the virus has created considerable issue world-wide and has major implications for both primary and secondary prevention strategies. The objective of this study was to establish the prevalence and genotype distribution of HPV in preinvasive, cervical intraepithelial neoplasia (CIN II and III) and invasive CCA in Sharkia governorate, Egypt. Methods: This study included 42 patients with CIN II and III, 30 patients with invasive CCA, and 45 controls who had undergone hysterectomy for any cause other than CCA. HPV detection and genotyping in cervical biopsies by Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP). Results: HPV DNA was detected in 85.7 \% (36 / 42) patients with CIN II and III. HPV genotypes were arranged in order of decreasing frequency as follows: HPV 16 being detected in 50.0\% (21 / 42), HPV 45 in 143\% (6 / 42), HPV 33 in 11.9 \% (5 /42), HPV 18 in 95\% (4 / 42) and HPV 31 in 7.1 \% (3 / 42) cases. In patients with invasive CCA, 93.3 \% (28 / 30) were positive for HPV DNA. In order of decreasing frequency, HPV genotypes were: HPV 16 being detected in 66.7 \% (20 / 30), HPV 18 in 16.7\% (5 / 30), HPV 33 in 10.0\% /30) and both HPV 31 and HPV 45 in 6.7 \% (2 / 30) cases. About 13.3 \% invasive cervical cancer and 7.1 \% CIN II\&III specimens exhibited multiple infections without significant difference (P > 0.05). HPV 16 and 33 infections show a higher risk for development of advanced stages of invasive CCA but without a statistically significant difference. Conclusions: The high prevalence of HPV genotypes 16, 18. and 45 in Sharkia governorate, Egypt, deserves attention as it has important implications for the usefulness of vaccine in prevention of a significant proportion of CCA and the choice of diagnostic methods. (Clin. Lab. 2011;57:363-371)