HPV/Pap triage in routine primary cervical cancer screening

Abstract

Cervical cancer can be prevented by cervical cytology screening which can detect the cancer cells and its precursors. The most common abnormal cytological finding encountered in screening program is “atypical squamous cells of undetermined significance (ASC-US)”. Human papillomaviruses (HPV) have been recognized as etiologic agents of cervical cancer. HPV DNA testing has been reported to be an option in the triage of women with ASC-US since ASC-US cases carrying high risk type HPVs were found to have markedly higher risk of harboring high grade cervical cancer precursors. Under current guidelines in most developed countries with available HPV test, women with ASCUS found to be positive for HPV can be referred for colposcopy directly while women who are HPV negative can be reassured and asked to rejoin cytology screening 12 months later. Prophylactic vaccines against HPV 6, 11, 16 and 18 have been adopted for protection against cervical cancer and genital warts. It is likely that the incidence of abnormal cervical cytology caused by vaccine type HPVs can be reduced leading to socioeconomic benefit. Since the immunity conferred by vaccines is type-specific, it is important to understand the prevalence of HPV genotypes in ASC-US to better predict the impact of HPV vaccine on possible change in prevalence of the disease in the community.