Summary Human papillomavirus (HPV) typing and quantitation by polymerase chain reaction was performed on exfoliated cells from 133 women referred for colposcopy because of an abnormal smear. High levels of HPV 16 correctly predicted cervical intraepithelial neoplasia (CIN) grade II-III in 93% of its occurrences, but only 59% of cases of CIN III were associated with high levels of this type. Eighty-four per cent of CIN III lesions contained high levels of at least one of HPV types 16, 18, 31, 33 and 35, but the other types were less specific for CIN III than HPV 16. Overall HPV testing compared favourably with cytology for predicting high-grade CIN lesions, but it would appear that some combination of the two modalities will produce better performance than either alone. In particular, HPV testing appears to be helpful in determining which women with mildly abnormal smears have high-grade underlying lesions in need of immediate referral for colposcopy.Cytological screening for cervical dysplasia is an effective method of reducing the incidence of and mortality from cervix cancer (Hakama, 1982; IARC Working Group, 1986;Laara et al., 1987;Hakama et al., 1991 (Barton et al., 1989;Szarewski et al., 1991). Possibly these can be safely left until the next routine smear, but invasive cancer can also be missed (Mitchell et al., 1990). Lastly, on the scale practised today, cytological examination of slides for dyskaryotic changes is a time-consuming, tedious and eye-fatiguing activity leading to difficulty in recruiting and keeping staff, and making the cost-effectiveness of the programme less favourable than it might be.In the past two decades much effort has been devoted towards trying to automate and simplify the preparation and reading of smears, and several prototype computer-assisted screening systems are under evaluation (Banda-Gamboa et al., 1992). However, none is currently in routine use, and interest in alternative or complementary modalities is high. The most thoroughly evaluated among these is cervicography (Stafl, 1981;Tawa et al., 1988;Szarewski et al., 1991), which is highly sensitive but does not appear to be sufficiently specific. However, the possibility that has stimulated the most interst is the detection and typing of HPV DNA in exfoliated cervical cells Schiffman et al., 1991;van den Brule et al., 1991;Koutsky et al., 1992 In this paper we extend that report by increasing the number of women studied and by looking individually at several HPV types. The specific aim was to examine the value of HPV typing for deciding which women with mild cervical abnormalities detected by cytology actually harbour a highgrade (CIN II/III) lesion and are in need of immediate referral for colposcopy. We also wished to examine the relative value of the different HPV types in predicing high-grade disease. The use of HPV DNA detection, typing and quantification in primary screening will not be addressed here and is the subject of several large ongoing studies.
Patients and methodsPatients referred for colposcopy were stu...