Objective: Although cervical screening has led to a significant decline of invasive cervical cancer (ICC) in developed countries, it remains the third leading cause of cancer in women worldwide. While the majority of the decline in ICC can be attributed to a reduction in squamous cell carcinoma (SCC), the incidence of cervical adenocarcinoma (ADC), absolute and relative to SCC, has been rising steadily, especially in younger women. This paper examines oncogenic human papillomavirus (HPV) infections, the risk of developing cervical ADC and its prognosis. It analyzes differences between ADC and SCC and considers current and future methods for prevention.
Methods: PubMed, publicly available websites and congress abstracts were searched for data and literature.
Results: HPV-16, -18 and -45 account for approximately 90% of ADC worldwide. Typically, α-7 genotypes, which include HPV-18 and -45, are more commonly associated with ADC than SCC. The difficulty in detecting ADC through screening as well as changing sexual habits and increased HPV transmission may account for its increase; an increase in SCC may not be observed because of improved detection of pre-malignant SCC compared with pre-malignant ADC. HPV testing shows promise for screening women ≥30years of age, but α-7 genotypes may be underrepresented in precancerous lesions. Clinical trial data indicate that current vaccines have high efficacy against HPV-16/18-related cervical intraepithelial neoplasia. Moreover, these vaccines also demonstrate a different level of protection beyond the HPV vaccine types, therefore increasing the overall vaccine efficacy. Such broad coverage could translate into a considerable reduction in the incidence of ADC.
Conclusion: Prophylactic HPV vaccination may have a significant impact on the prevention of ADC and may significantly impact future strategies for primary and secondary prevention of cervical cancer.
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