Urine collection in cervical cancer screening – analytical comparison of two HPV DNA assays

BACKGROUND: To reach non-participants, reluctant to undergo clinician-based cervical cancer screening and vaginal self-sampling, urine collection for high-risk human papillomavirus detection (hrHPV) may be valuable. Using two hrHPV DNA assays, we evaluated the concordance of hrHPV positivity in urine samples in comparison with vaginal self-samples and cervical cytology samples taken by the general practitioner (GP). We also studied women’s acceptance of urine collection and preferences towards the different sampling procedures. METHODS: One hundred fifty paired self-collected urine and vaginal samples and GP-collected cervical cytology samples were obtained from 30 to 59-year-old women diagnosed with ASC-US within the Danish cervical cancer screening program. After undergoing cervical cytology at the GP, the women collected first-void urine and vaginal samples at home and completed a questionnaire. Each sample was hrHPV DNA tested by the GENOMICA CLART® and COBAS® 4800 assays. Concordance in hrHPV detection between sample types was determined using Kappa (k) statistics. Sensitivity and specificity of hrHPV detection in urine was calculated using cervical sampling as reference. RESULTS: With the COBAS assay, urine showed good concordance to the vaginal (k = 0.66) self-samples and cervical samples (k = 0.66) for hrHPV detection. The corresponding concordance was moderate (k = 0.59 and k = 0.47) using CLART. Compared to cervical sampling, urinary hrHPV detection had a sensitivity of 63.9% and a specificity of 96.5% using COBAS; compared with 51.6 and 92.4% for CLART. Invalid hrHPV test rates were 1.8% for COBAS and 26.9% for CLART. Urine collection was well-accepted and 42.3% of the women ranked it as the most preferred future screening procedure. CONCLUSIONS: Urine collection provides a well-accepted screening option. With COBAS, higher concordance between urine and vaginal self-sampling and cervical sampling for hrHPV detection was found compared to CLART. Urinary hrHPV detection with COBAS is feasible, but its accuracy may need to be improved before urine collection at home can be offered to non-participants reluctant to both cervical sampling and vaginal self-sampling.