Role of human papillomavirus in the pathogenesis of genital tract warts and cancer.

During the last decade a large number of clinical, epidemiological, and experimental studies have elucidated the role of HPV in the pathogenesis of anogenital cancer. Although the clinical and epidemiological studies have been criticized for a variety of technical and design shortcomings, for the most part they have independently reached the same conclusion--there is a strong association between the presence of specific types of HPV and the development of anogenital cancer. Similarly, laboratory studies clearly indicate that specific types of HPV act in concert with other cellular changes to transform a variety of cell types in vitro, including human cervical epithelial cells. Over the next decade the challenge is twofold. First we need to define precisely the mechanisms by which HPV either by itself or in concert with other factors, acts to transform anogenital epithelial cells. These studies will, it is hoped, identify important cofactors in the transformation process and determine the role of host immunity. Second, we need to determine the clinical applicability of the association between HPV and anogenital cancer. Large clinical studies will determine whether HPV testing of asymptomatic patients facilitates the detection of patients at risk for developing cervical cancer and whether the presence of a specific type of HPV in a cervical cancer actually affects a patient's prognosis. As the answers to these and other questions become available, we will be in a better position to assess the clinical importance of the associations between HPV and anogenital cancer.