The incidence of cervical cancer has dropped dramatically due to the success of the Papanicolaou (Pap) test, (the cytologic examination of cervical cells) in the detection of high-grade premalignant lesions that can be treated before they progress to invasive cervical carcinoma. Although the Pap test is the most effective tool ever deployed for cancer screening, it has been limited by problems of low sensitivity for high-grade premalignant lesions of the cervical mucosa.
Epidemiologic and molecular studies over the past three decades have firmly established that human papillomavirus (HPV) infection is the etiologic agent for virtually all cases of cervical squamous cell carcinoma (SCC) and also for the vast majority of cases of endocervical adenocarcinoma. Although the development of HPV-based test strategies can be used to enhance sensitivity for the detection of clinically significant lesions, HPV testing has been less effective as a primary screening assay in patient populations that have a high prevalence of HPV infection, including adult women under age 30 in both industrialized nations and many third-world countries. In addition, the incidence of death due to cervical cancer has not changed in many developing countries due to difficulties in introducing cost-effective and highly sensitive and specific cervical cancer screening programs that do not require a large clinical laboratory infrastructure and trained cytotechnologists to analyze results. Hence, there is a significant need for a new generation of molecular tests that can augment the existing Pap test, and potentially replace the HPV or Pap tests as the frontline screen in developing countries.
Unmet clinical needs in cervical cancer screening
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