HPV HANDBOOK - Zervita

HPV TESTING AS A SCREENING TEST: THE CASE AGAINSTSpecificity issuesSpecificitySpecificity: the probability that a test will be negative, given thatthe individual being tested does not have the diseaseThe specificity of HPV testing is almost invariably found to be lowerthan that of cytology, especially in younger women. 18 Reducing thenumber of false-positive results during screening is particularlyimportant, as they introduce unnecessary investigational costs andinduce anxiety in women. Indeed, it has long been recognized thatfocusing on high sensitivity, to the detriment of low specificity, is apoor strategy for public health purposes. Under circumstances wherethe disease has a long natural history and involves regression, andwhere repeat testing at least every 3 to 5 years is generally envisaged,undue emphasis on high sensitivity at the expense of specificity wouldbe a serious error.OverviewFor women >35 (or preferably >40) years of age with cytologicallynegative smears, HPV testing may prove valuable in confirming thatthey have no evidence of infection with an oncogenic HPV virus. Undersuch circumstances, it is probable that repeat screening would beunnecessary for at least 5 and probably 10 years. An importantrequirement would be that such women should remain in a stablerelationship and that neither they nor their partner should acquire anew HPV infection, otherwise their risk of developing progressive CINwould relapse to the same level as that for a woman aged 35 yearswho is HR HPV-positive.Simply testing for HPV infection, when the great majority of infectionsare transient, makes little sense. Testing for the consequences of suchinfection (i.e. CIN) with cytology is more logical, but only if aconservative approach to management is followed. Therefore,39