Genital human papillomavirus (HPV) infections and their importance for the handling of precancerous lesions of the cervix uteri

GENITAL HUMAN PAPILLOMAVIRUS (HPV)INFECTIONS AND THEIR IMPORTANCE FOR THEHANDLING OF PRECANCEROUS LESIONS OF THE CERVIX UTERI Keng-Ling Chua Background: The developmentof cervical carcinoma, in a vast majorityof cases, is closely related to infectionswith certain types of the humanpapillomavirus (HPV). The virus is sup-posed to exert its oncogenic effect mainlythrough interference with two proteinsthat are responsible for growth arrest asa response to DNA damage. The infectionis an early event in the development of thistumour, and the further carcinogenesisprobably necessitates additional co-fac-tors. The development of invasive car-cinoma of the cervix uteri can to some ex-tent be prevented through cytologicalhealth control screening and subsequenttreatment of detected precursor lesions.Many cases of such cancer will, however,develop in spite of screening, mainly dueto lack of sensitivity of the cytological test. One way to improve the sensitiv-ity in detecting patients at risk for devel-oping cervical carcinoma may be an addi-tional search for HPV infections. This canbe done using morphology, molecular bi-ology or immunology; all these techniquesvary in sensitivity and specificity. Aims: These studies were under-taken to evaluate the diagnostic signifi-cance of various cytomorphological find-ings; to validate and compare different di-agnostic methods for the diagnosis of anHPV infection and to exploit the possi-ble clinical use of HPV testing as a meanto detect precancerous lesions in other-wise healthy women and as follow-upafter treatment for such lesions. Findings: All tested cytomor-phological criteria were significantlymore common among infected patients,although only three of them: koilocytosis,parakeratosis and/or dyskeratosis andkaryorrhexis, were of major diagnosticimportance. These morphological crite-ria, Southern blot and PCR analysis canall be used to specifically diagnose HPVinfections. The clinical sensitivity of thecytological algorithm is