Impact of reflex HPV testing on interpretation and management of ThinPrep Pap tests

HPV testing for high-risk types is the preferred method to triage women with atypical squamous cells (ASC) on ThinPrep Pap tests for management. The impact of this practice on the cytopathologists' interpretation is unknown. A significant percentage of providers at the Beth Israel Deaconess Medical Center (BIDMC) are not requesting reflex HPV testing. This offers a unique opportunity to examine its impact. Consecutive ThinPreps submitted to the cytology laboratory at the BIDMC for a 3-mo period were identified retrospectively. The ThinPreps were divided into those with a request for reflex HPV testing (reflex testing request group), those without such a request, and those with a request for HPV testing regardless of the diagnosis. Cytologic diagnoses, results of HPV testing and subsequent cervical biopsies within 6 mo after the ThinPrep were recorded and correlated in these cases. A total of 4,590 ThinPreps were processed during this period. 2,659 had a request for reflex HPV testing, 1,849 did not have such a request, and 82 had a request for HPV testing regardless of diagnosis. The numbers (%) of abnormal results in these three groups were 155 (5.8%), 141 (7.6%), and 22 (27%), respectively. The ASC:SIL ratios for these three groups were 1.2, 0.86, and 0.62, respectively. 38/71 (54%) women with ASC in the reflex testing request group were positive for high-risk HPV types. Of those with ASC in the reflex testing request and no request groups, 15/73 (21%) and 12/56 (21%) underwent biopsies with 2 (of 15) and 2 (of 12) showing HSIL on histology, respectively. Our study demonstrates that at our institution a request for reflex HPV testing did not significantly affect cytopathologists' interpretation of ThinPreps. Furthermore, HPV testing did not seem to have influenced the subsequent management of women with ASC diagnosis.