Women who self-screened for high-risk human papillomavirus (hrHPV) had similar test results to those who were screened by a clinician, according to a study published in BMJ.

A research team assessed the accuracy and utilization of self-sampling for hrHPV testing by reviewing 2 meta-analyses that included research published through April 15, 2018.  The first meta-analysis (n=56) included studies that assessed the diagnostic accuracy of self-sample vs clinician sample for hrHPV testing to detect cervical intraepithelial neoplasia grade 2 (CIN2+) or worse (CIN3+) and compared results based on clinical setting, assay, self-sampling device, and storage medium. The second meta-analysis (n=25) included randomized clinical trials that assessed response rates to an offer of self-sampling kits vs a mailed invitation/letter to women who were underscreened.

The accuracy studies were eligible if the following criteria were met: a vaginal sample was collected by the patient herself (self-sample) followed by a cervical sample collected by a clinician (clinician sample); hrHPV assay was performed on both samples; and the presence or absence of CIN2+ was verified by colposcopy or biopsy in all enrolled women or women with 1 or more positive test results. The participation studies were eligible if the following criteria were met: the study population comprised women who were never or irregularly screened; women in the intervention group obtained a self-sample; women in the control group were invited or reminded to undergo clinician sampling; all participation was documented; and at least 400 women were included in the study.

The pooled absolute sensitivity of hrHPV assays for CIN2+ was found to be lower in self-samples (77%; 95% CI, 69%-82%) than in clinician samples (93%; 95% CI, 89%-96%). The pooled absolute sensitivity of hrHPV assays for CIN2+ based on polymerase chain reactions was 96% for both self-samples and clinician samples.  The relative accuracy of hrHPV assays on self-samples vs clinician samples did not vary substantially by clinical setting.  


Continue Reading

hrHPV assays based on signal amplification were less sensitive (ratio, 0.85) and less specific (ratio, 0.96) on self-samples vs clinician samples. The test positivity rate was 14% higher and the positive predictive value was significantly lower for both CIN2+ and CIN3+ for self-samples. hrHPV assays based on polymerase chain reaction were equally sensitive (ratio, 0.99 for CIN2+; ratio, 0.98 for CIN3+) but less specific (ratio, 0.98 to exclude CIN2+) on self-samples vs clinician samples.

The percentage of women in the self-sampling arm who completed a self-sampling test when mailed to her home varied between 6.4% and 34.0% (average, 19.2%) in the per-protocol analysis. The pooled percentage of participating women in the intention-to-treat analysis of the self-sampling arm was 17.7% in the opt-in scenario and 94.6% in the door-to-door scenario. The average percentage of women who participated in the control arm was 11.5% in the mail-to-all scenario, 13.4% in the opt-in scenario, 6.0% in the community campaigns scenario, and 53.3% in the door-to-door scenario. Participation was not significantly different when hrHPV testing was performed vs cytology (P =.60 vs P =.76).

The relative participation rate was 1.87-times and 2.33-times higher in the self-sampling arm compared with the control arm of the trials with a mail-to-all scenario, in the per-protocol and intention-to-treat analyses, respectively. For trials with opt-in scenarios, per-protocol analysis revealed a lower participation rate in the self-sampling vs control arm (0.73), whereas in the intention-to-treat analysis, relative participation of the self-sampling arm exceeded the control arm (1.22). Participation rates decreased with increasing length of time since last screening in both arms.

Related Articles

In women with self-samples that tested positive for hrHPV, 80.6% had a follow-up examination. Adherence to follow-up was lower in the self-sampling arm vs in the control arm, but this finding was not statistically significant. The CIN2+ detection rate in the self-sampling arm varied between 0 and 11 per 1000 screened women. On average, the detection rate of CIN2+ was 2.28-times higher in the self-sampling arm vs the control arm. The detection rate ratio varied with a greater detection rate ratio (P =.031) in women with a self-sample that tested positive for hrHPV who were directly referred for colposcopy. The detection rate varied between 0 and 35 per 1000 screened women. The detection rate per number of screened women was similar in the 2 arms (relative proportion, 1.13).

The authors conclude that “hrHPV testing with an appropriate assay offers a promising new strategy that could increase population coverage substantially.”

Reference

Arbyn M, Smith SB, Temin S, Sultana F, Castle P; on behalf of the Collaboration on Self-Sampling and HPV testing. Detecting cervical precancer and reaching underscreened women by using HPV testing on self samples: updated meta-analyses. BMJ. 2018;363:k4823.