Variants of human papillomavirus types 16 and 18: histological findings in women referred for atypical glandular cells or adenocarcinoma in situ in cervical smear

Human papillomavirus (HPV) genotypes cannot fully explain the histological diagnosis of women with glandular abnormalities detected by cervical smear. Thus, this study was designed to analyze the distribution of HPV-16 and HPV-18 variants in women referred because of atypical glandular cells and adenocarcinoma in situ in their cervical smears and its association with histological results. Twenty-four women with HPV-16 and 6 with HPV-18, selected from 160 women with cervical smears suggestive of glandular abnormalities, were included. Histological results showed cervicitis (1 case), squamous neoplasia (18 cases), glandular neoplasia (7 cases), and glandular neoplasia associated with a squamous component (4 cases). Among the 24 cases presenting HPV-16, the European variant was detected in 15 (62%) and the Asian American in 9 (38%). Among the 15 cases associated with the European variant, 14 (93%) presented squamous neoplasia and 1 (7%) invasive adenocarcinoma. Asian-American HPV-16 variants were significantly associated with histological diagnosis of glandular neoplasia alone (odds ratio, 9.3 [1.4-60.2]) or associated with squamous neoplasia (odds ratio, 18.7 [1.5-232.3]). Adenocarcinomas were detected in 4 of 6 HPV-18-positive cases, being 2 cases had the European variant, 1 had the Asian Amerindian variant, and 1 had the African variant. The association of HPV-16 with squamous or glandular neoplasia is explained by its variants. In this study, squamous neoplasia was related to the European variant of HPV-16, whereas glandular neoplasia was related to the Asian-American variant. Glandular neoplasia is associated with HPV-18, but the results of our analysis of its variants were inconclusive.