Screening history of cervical cancers in Emilia-Romagna, Italy: defining priorities to improve cervical cancer screening.

Most invasive cervical cancers in industrialized countries are due to the lack of Pap test coverage, very few are due to screening failures. This study aimed at quantifying the proportion of invasive cancers occurring in nonscreened or underscreened women and that in women with a previous negative screening, that is, screening failure, during the first two screening rounds (1996-2002) and in the following rounds (2003-2008) in the Emilia-Romagna region. All cases of invasive cancers registered in the regional cancer registry between 1996 and 2008 were classified according to screening history through a record linkage with the screening programme registry. The incidence significantly decreased from 11.6/100 000 to 8.7/100 000; this decrease is due to a reduction in squamous cell cancers (annual percentage change -6.2; confidence interval: -7.8, -4.6) and advanced cancers (annual percentage change -6.6; confidence interval: -8.8, -4.3), whereas adenocarcinomas and microinvasive cancers were essentially stable. The proportion of cancers among women not yet invited and among nonresponders decreased over the two periods, from 45.5 to 33.3%. In contrast, the proportion of women with a previous negative Pap test less than 5 years and 5 years or more before cancer incidence increased from 5.7 to 13.3% and from 0.3 to 5.5%, respectively. Although nonattendance of the screening programme remains the main barrier to cervical cancer control, the introduction of a more sensitive test, such as the human papillomavirus DNA test, could significantly reduce the burden of disease.