OBJECTIVETo determine the association between viral load of high risk type human papillomavirus (HR-HPV) and stage of cervical intraepithelial neoplasia (CIN) lesion.

METHODSCervical exfoliated cells were collected from 1997 women aged 35-45 in a cross-sectional screening study. HPV DNA was detected by hybrid capture 2 (HC2) system, and viral load was measured by the ratios of relative light units compared to standard positive control (RLU/PC). Log10RLU/PC were categorized into four groups: negative (< 0), low viral load (0 - 1.12), medium viral load (1.13 - 2.23), and high viral load (2.24 - 3.37). Cervical lesions were diagnosed by biopsies as normal, CIN 1, CIN 2-3, and squamous cervical cancer (SCC). Association between HR-HPV and CINs were evaluated by unconditional multinomial logistic regression.

RESULTS100% (12/12) SCC, 97.3% (72/74) of CIN 2-3, 58.3% (74/127) of CIN 1, and 11.5% (205/1784) of normal women were positive for HPV DNA. The median log10RLUs for the positive women with SCC, CIN 2-3, CIN 1 and in normal women were 2.60, 2.32, 2.18 and 1.18 respectively. The odds ratio (OR) between low viral load of HPV DNA and CIN 1 was 3.8 (1.9 - 7.3) while between high viral load and CIN 2-3 was OR=865.9 (200.1 - 3738.0) which showed that higher viral load could increase the risk of cervical lesions (P <0.001).

CONCLUSIONBoth cervical cancer and CINs were highly influenced by HR-HPV viral load.