Lyufang Duan

The effectiveness of HPV viral load, reflected by Cobas 4800 HPV-Ct values for the triage of HPV-positive women in primary cervical cancer screening: Direct endocervical samples

To explore the relationship between the viral load reflected by the Ct value of Cobas 4800 HPV test and cervical lesions, and the effectiveness of the viral load for secondary triage of HPV-positive women. The Chinese Multi-Center Screening Trial (CHIMUST) evaluated both self-collected samples and physician-collected samples from women, aged 30 to 59, who were screened for cervical cancer in 6 regions across China. Using physician collected samples, the relationship between the HPV-Ct values of different subtypes and the cervical lesions was analyzed. Then the combined use of the HPV-Ct values with the HPV subtypes was evaluated as a secondary screening algorithm for the women who were HPV positive. The Ct values of HPV16 and 12 other HPV subtypes(12-type pool), tested with Cobas decreased with the progression of cervical lesion (HPV16: r = -0.429, P0.05). Compared with HPV16/18 and cytology (HPV16/18 positive and 12-type pool plus cytology ≥ ASC-US), the sequential secondary screening using HPV16/18 and the viral load of 12-type pool (cut-point HPV-Ct≤31) had equal sensitivities for CIN2+ and CIN3+ (83.1%vs.80.3%,100%vs.92.6%,P>0.05), with slightly lower specificities (96.2%vs.94.4%,96.5%vs.93.9%,P<0.001) and higher colposcopy referral rate (4.90%vs.6.59%, P<0.05), but required no cytology. Type-specific HPV viral load is closely related to cervical lesions severity. It is feasible and efficient to use HPV16/18 and the viral load of 12 other HPV subtypes (with cut-point HPV-Ct≤31) as the secondary screening for HPV positive women. This algorithm may be useful in low resource regions.

The application of BMRT-HPV viral load to secondary screening strategies for cervical cancer

Evaluate the significance of BMRT HPV assay viral load and its performance for secondary screening. BMRT-HPV reports type-specific viral loads/10,000 cells. We tested 1,495 physician collected, stored specimens from Chinese Multiple-center Screening Trial (CHIMUST), that were positive by Cobas, SeqHPV, and/or Cytology (≥LSIL); and 2,990 age matched, negatives in a nested case control study. We explored the relationship between BMRT HR-HPV viral load and cervical lesions, determined alternative CIN2+ cut-points by ROC curve, and evaluated BMRT HR-HPV for primary / secondary cervical cancer screening. The viral loads of HPV16/18, 12 other subtypes HR-HPV and 14 HR-HPV were statistically different in all grades of cervical lesions (P0.05), specificity was higher than Cobas (84.8% vs 83.3%, 83.5% vs 82.0%, P0.05). However, the BMRT HR-HPV viral load combined with subtypes did not require cytology. BMRT is as sensitive as Cobas4800 for primary cervical cancer screening. BMRT HR-HPV viral load combined with subtypes can be used as a secondary strategy for cervical cancer screening, especially for areas with insufficient cytological resources.