Abstract C59: Human papillomavirus genotype distribution in northern India: Implications for vaccination

Abstract

Abstract Background: Cervical cancer caused by human papilloma virus (HPV), is the commonest cancer in Indian women, with an estimated 132000 new cases and 76000 deaths annually. More than 100 HPV genotypes have been identified in humans of which at least 40 HPV types are found in the genital tract. Several high-risk HPV types are known to cause the disease. There are only limited data available on the genotype distributions in this region. Methods: During the period three different cross-sectional studies were carried out: (1) a hospital-based cross-sectional study in which 106 women presenting with invasive cervical cancer; (2) a hospital-based cross-sectional study in which 524 women presenting to have an unhealthy cervix were invited to participate; (3) a community-based cross-sectional study in which 465 women also underwent HPV testing. HPV typing in these studies was done by using L1 consensus PCR followed by reverse line blot hybridization assay (Roche). Results: In the hospital-based population, among 106 invasive cervical cancers the six commonest HPV types were HPV-16, -18, -45, -59, -33 and 73. HPV-16/18, singly or in combination, were seen in 83% of cases. (2) In the hospital-based population, among the 524 symptomatic hospital subjects, the overall HPV prevalence was 15.5 % and the six commonest HPV types were as follows: HPV -16, -89, -39, -52, -33 and 18. Among the HPV positive women accounted for HPV-16/18 were associated with 34.3%, 45.4% and 65.7% of normal, low-grade and high-grade disease respectively. Among (3) the community-based women, the overall HPV prevalence was 7 % and the six commonest HPV types were as follows: HPV- 16, - 45, -52, -31, -66, and -18. Conclusions: A wide spectrum of HPV types is seen in north Indian women, with HPV-16/18 are the commonest types in all populations. However, thereafter there is considerable variation. It is estimated that the HPV -16/18 vaccine would reduce over 75% of the total cancer burden in this region. The community population is from a confined geographical area whereas the hospital population includes not only residents of Delhi and neighbouring areas but also further states of North India as well as neighboring countries of Nepal and Bangladesh. Thus more studies are required to establish the true picture of HPV type-distribution in this large and diverse region. Citation Information: Cancer Res 2009;69(23 Suppl):C59.