HPV type distribution in invasive cervical cancers in Italy: pooled analysis of three large studies
1 AUSL Reggio Emilia, via Amendola 2, Reggio Emilia 42122, Italy
2 European Institute of Oncology, Milan, Italy
3 ISPO Toscana, Florence, Italy
4 National Cancer Institute Regina Elena, Rome, Italy
5 National Cancer Institute Fond Pascale, Naples, Italy
6 Agency for Public Health, Lazio Region, Rome, Italy
Infectious Agents and Cancer 2012, 7:26 doi:10.1186/1750-9378-7-26Published: 12 October 2012
The aim of this study is to describe the prevalence of HPV types in invasive cervical cancers in Italy from 1996 to 2008.
A pooled analysis of the three largest case series typed to date was performed. HPV typing was performed on paraffin-embedded slices. Molecular analyses were performed in four laboratories. Multivariate analyses were performed to test the associations between calendar time, age, and geographical area and the proportion of types 16/18.
Out of 574 cancers, 24 (4.2%) were HPV negative. HPV 16 and 18 were responsible for 74.4% (378/508) and 80.3% (49/61) of the squamous cancers and adenocarcinomas, respectively. Other frequent types were 31 (9.5%), 45 (6.4%), and 58 (3.3%) for squamous cancers and 45 (13.3%), 31, 35, and 58 (5.0%) for adenocarcinomas. The proportion of HPV 16 and/or 18 decreased with age (p-value for trend <0.03), while it increased in cancers diagnosed in more recent years (p-value for trend < 0.005).
The impact of HPV 16/18 vaccine on cervical cancer will be greater for early onset cancers. In vaccinated women, screening could be started at an older age without reducing protection.