Human Papillomavirus Genotypes and Cofactors Causing Cervical Intraepithelial Neoplasia and Cervical Cancer in Korean Women

Infection with human papillomavirus (HPV) is a necessary cause of cervical cancer, but the risk associated with the various viral types and related cofactors have not been adequately assessed in Korean women. This study aimed to investigate the genotype distribution of HPV and cofactors related to cervical carcinogenesis in Korean women. We conducted a hospital-based case-control study in 215 women with histologically confirmed cervical neoplasia (111 cases of cervical intraepithelial neoplasia [CIN] and 104 cases of invasive cervical cancer [ICC]) and 1214 healthy control women. Polymerase chain reaction-based dot blot assays were used for detection of 16 highrisk HPV types. To clarify the cofactors, we administered questionnaires evaluating smoking, drinking, and sexual and reproductive history from women infected with HPV. Human papillomavirus was detected in 86.5% of the women with CIN and 96.2% of the women with ICC compared to 14.6% of the control women. The most common HPV types were, in descending order of frequency, types 16, 58, 18, 33, and 66 for CIN, and types 16, 18, 31, and 33 for ICC. Among the control women, HPV 16, 66, 33, 58, 18, and 31 were the most common types. Smoking and higher number of births (Q3) were associated with CIN (odds ratio [OR], 2.49; 95% confidence interval [CI], 1.21-5.15, and OR, 2.67; 95% CI, 1.36-5.28, respectively). This relationship was also found in the women with ICC (OR, 3.42; 95% CI, 1.59-7.38, and OR, 2.17; 95% CI, 1.08-4.38, respectively) compared to controls. In addition, the circumcision of sexual partner and the sexual habit of condom use were protective factors for ICC (OR, 0.47; 95% CI, 0.24-0.90, and OR, 0.19; 95% CI, 0.06-0.57, respectively). Human papillomavirus types 16, 18, 31, 33, and 58 are the major causative genotypes for cervical carcinogenesis in Korean women. Smoking and multiparity seem to be the most significant cofactors.