BACKGROUND: Several options for the triage of high-risk HPV screen positive (hrHPV+) women were assessed.
METHODS: This study incorporated CIN2+ cases and controls, all of whom tested hrHPV+ and whose results of liquid-based cytology (LBC), HPV16/18 genotyping and p16/Ki67 cyto-immunochemistry were available. Sensitivity and specificity for the CIN2+ of these triage tests were evaluated.
RESULTS: Absolute sensitivities of HPV 16/18 typing, LBC and p16/Ki-67 cyto-immunochemistry for CIN2+ detection were 61.7%, 68.3% and 85.0% for women with hrHPV+ clinician-taken samples. Respective specificities were 70.5%, 89.1% and 76.7%. The absolute accuracy of the triage tests was similar for women with a hrHPV+ self-sample. P16/Ki-67 cyto-immunochemistry was significantly more sensitive than LBC although significantly less specific.
CONCLUSIONS: All three single test triage options, if positive, exceed the threshold of 20% risk at which colposcopy would be indicated. However, none of them conferred a post-test probability of CIN2+ <2%; which would permit routine recall. P16/Ki-67 cyto-immunochemistry on HPV16/18 negative women had a post test probability of CIN2+ of 1.7% and 0.6% if also LBC negative.
IMPACT: This is one of the few studies to directly compare the performance of triage strategies of hrHPV+ women, in isolation and combinations. It is the only study assessing triage strategies in women who test hrHPV+ in self-taken vaginal samples. A combined triage option which incorporated HPV 16/18 typing prior to p16/ki-67 cyto-immunochemistry in HPV 16/18 negative women yielded a post test probability of CIN2+ of >20% while women who tested negative had a probability of CIN2+ of <2%.