Survey of human papillomavirus infection in cervical intraepithelial neoplasia in Thai women.

HPV infection is known to be associated with cervical cancer development. Precancerous lesions named cervical intraepithelial neoplasia (CIN) are divided into 3 grades, i.e., CIN-1, CIN-2, and CIN-3. Here, HPV infection determined by PCR and dot hybridization was observed in these 3 different grades of formalin-fixed paraffin embedded tissues. The HPV infection was demonstrated in 33.3 per cent of CIN-1, 36.8 per cent of CIN-2 and 75 per cent of CIN-3. Using type specific probes for HPV-6, 11, 16, 18 and 33, HPV-16 was the most prevalent type (44.44%) followed by HPV-18 (16.05%) in CIN-3. Only one HPV-18 was identified in CIN-1 while CIN-2 contained one HPV-6 and one HPV-18. Mixed infection was found in CIN-3 (12.35%). All of them had HPV-16. The cervicitis cases with normal histopathology were included as control. Only 2.7 per cent of HPV infection was shown. The relative risk of HPV infection was high in CIN-3 (OR = 107.25, 95% CI = 50.29-228.73). Our data confirm the association between high-risk HPV types and development of CIN.