HPV testing may also have other roles within the screening programme. The most obvious is in improving the management of women with low-grade or borderline smears. In this context, HPV testing can help identify which women are in need of immediate referral for colposcopy. However, there is still uncertainty about the negative predictive value, and the safety associated with reduced surveillance in HPV-negative women. HPV testing has also been proposed for post-treatment surveillance of CIN, and early cancer, to monitor for complete excision.
Early results look very promising, but more, better designed studies are needed here.
Modelling A number of possibilities exist for introducing HPV testing at different ages and at different screening intervals. It could be used as the sole primary screening modality, as an adjunct to cytology, or in the triage of borderline and mild dyskaryosis. Published modelling studies are limited by the estimates of effectiveness, which are only now becoming available, and the cost of the test, which is still not known for high-volume applications. In the time available, only baseline calculations could be performed. These were sufficient to show that current knowledge is inadequate for assessing cost-effectiveness.