A cornucopia of screening and diagnostic techniques for human papillomavirus associated cervical carcinomas

Cervical carcinoma is one of the major consequences of human papillomavirus (HPV) infections. Although HPV infections of cervix do not always progress to cancer, 90% cases of cervical cancer have been found associated with high risk HPV (hrHPV) infection. Usually, HPV infection is asymptomatic; however, this asymptomatic infection can cause abnormal changes in cervix ultimately leading to cancer development. These changes can be detected by the application of screening tests at regular time intervals. For this purpose, morphological, cytological, and DNA based techniques are available. Nevertheless, abnormal screening tests have only the predictive value for precancerous lesions and thus require further evaluation which is usually done by using diagnostic techniques. So far, colposcopy and histological examination alone were considered as the gold standards for cervical cancer diagnosis. Currently, some tests based on expression level of host cell biomarkers are also being used along with histology for diagnostic purpose. Albeit, these tests have significant specificity and sensitivity values but they are unable to suggest a particular viral genotype involved in infection. Diagnostic methods such as PCR, HPV genotyping assays, microarray, and mRNA based assays are useful to predict the genotypes as well as the quantity of viral load in a host cell. Similarly, these diagnostic procedures have high specificity and sensitivity ranges. However, only few of them are practiced commonly, as approval of these tests as routine diagnostic tests requires clinical validation and cost effectiveness.