Molecular epidemiology of human papillomavirus genotype in women with high-grade squamous intraepithelial lesion and cervical cancer: will a quadrivalent vaccine be necessary in Thailand?

This study was designed to investigate the distribution of human papillomavirus (HPV) genotypes among a group of patients with high-grade squamous intraepithelial lesion (HSIL) or worse cytology. Consequently, the genotype-specific HPV infection in a group of HSIL and invasive cervical cancer (ICC) samples was described. Specimens were collected prospectively from 132 women referred for colposcopic examination. All the women underwent Papanicolaou (Pap) smears and colposcopies and some also underwent cervical excision procedure biopsy. The HPV genotype was determined using the INNO-LiPA assay. Among the 132 genotyped samples, 90.91% (120/132) were diagnosed HSIL, whereas 9.09% (12/132) were ICC. From the overall prevalence of HPV in the patients, 77.27% (102/132) and 22.72% (30/132) of cases had single and multiple genotype infections, respectively. The most common cases with statistical significance were high-risk HPV (HR-HPV) infections in 128 samples (96.97%), whereas, four individuals (3.03%) barely were low-risk HPV (LR-HPV) infected, P < 0.0001, χ(2). The most prevalent genotypes were frequently HPV-16 (65/167; 38.92%, followed by HPV-58 (25/167; 14.97%), HPV-18 (18/167; 10.78%), HPV-33 (13/167; 7.19%), and HPV-68 (11/167; 6.59%). In addition, HPV-11 (2/132; 1.51%) and HPV-6 (1/132; 0.76%) also were observed in this study, which confirmed the high distribution of HR-HPV among women with HSIL and ICC. HPV-58; a unique high-risk HPV, is prevalent in a group of HSIL and ICC cases. These data also contribute evidence that HPV-16, -18, -58, -33, and -68 genotypes are high-risk and high distribution among women with HSIL and ICC. Therefore, HPV-58, HPV-33, and HPV-68 should be considered for development of the next vaccine generation in Thailand.