P13-06ROLE OF HPV VIRAL LOADS IN GUIDING BIOPSY UNDER COLPOSCOPY FOR ASC-US AND HPV POSITIVE WOMEN

13. Screening methods
X.Q. Xu 1, L. Zhang 1, S.Y. Hu 1, Q. Zhang 1, R.M. Feng 1, R. Rezhake 1, X.L. Zhao 1, F. Chen 1, X. Zhang 2, Q.J. Pan 3, Y.L. Qiao 1, F.H. Zhao 1.
1Department of Epidemiology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China), 2Department of Pathology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China), 3Department of Cytology, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

Background / Objectives

Improvement remains on subsequent management of women with concurrent atypical squamous cells of undetermined significance (ASC-US) cytology and positive HPV results. The aim of our study was to explore the role of HPV viral loads in guiding biopsy under colposcopy for ASC-US and HPV positive women.


Methods

We performed a pooled analysis of 17 population-based cross-sectional studies conducted in China from 1999 to 2008. 30,371 women were screened with liquid-based cytology (LBC), HPV testing (hybrid capture 2, HC2) and visual inspection with acetic acid test (VIA) and diagnosed by colposcopically-directed biopsies. HPV viral loads were stratified as low[1.0, 10.0), intermediate[10.0, 100.0) and high [100.0, +∞) in RLU/CO value. Risks of cervical intraepithelial neoplasia grade 2 or worse(CIN2+) among different viral load groups were analysed with linear trend Chi-square test and relative CIN2+ risks among groups were calculated with logistic regression analysis.


Results

908 ASC-US women with positive HPV and complete biopsy results were included in final analysis, among whom, 649, 170 and 89 women were diagnosed as normal, CIN1 and CIN2+, with median value of HPV viral loads as 23.15(4,46,121.91), 85.53(18.73,367.90) and 95.68(18.95, 370.34), respectively. CIN2+ risks increased significantly with elevating of viral load levels(p trend<0.001). Women with intermediate and high viral loads showed at least 67.60(20.52,222.50) times higher CIN2+ risk than ASC-US but HPV negative women. Among 37 CIN2+ cases missed by colposcopy, 72.9% were at intermediate to  high viral load range and this proportion achieved 81.8% among cervical intraepithelial neoplasia grade 3 or worse(CIN3+) cases.  As for ASC-US women at low viral load and relative lower CIN2+ risk, though an abnormal colposcopy result did not increase the CIN2+ risk significantly, it showed 7.61(1.36, 42.62) times higher CIN3+ risk than a negative colposcopy result.


Conclusion

​Intermediate to high HPV viral loads in ASC-US and HPV positive women effectively predict a significantly increased risk of existing CIN2+ and should be biopsied regardless of colposcopy results. As to those with low HPV viral loads, only abnormal colposcopy result are supposed to be referred to guide biopsy, ensuring high CIN2+ detection rate and less biopsy harms concurrently.


References