Department of Gynecology and Obstetrics, Faculty of medicine and biomedical sciences, University of Yaoundé, Cameroon.
Int J Cancer. 2015 Mar 15;136(6):E743-50. doi: 10.1002/ijc.29250. Epub 2014 Oct 18.
The World Health Organization recently advocated a two-stage strategy with human papillomavirus (HPV) testing followed by visual inspection of the cervix with acetic acid (VIA) as a suitable option for cervical cancer screening. However, its accuracy has never been directly assessed in the context of primary screening. To evaluate effectiveness of HPV testing on self-obtained specimens (self-HPV) followed by VIA (sequential testing) in a low-income setting, we recruited 540 women aged between 30 and 65 years in two Cameroonian periurban areas. Eligible women were counseled about cervical cancer and how to perform self-sampling. HPV positive and a random sample of HPV-negative women were called back for VIA and biopsy. Disease was defined by interpretation of cervical intraepithelial neoplasia Grade 2 or worse (CIN2+). Performances of VIA, self-HPV and sequential testing were determined after adjustment for verification bias. HPV prevalence was 27.0%. VIA positivity was 12.9% and disease prevalence was 5%. Sensitivity and specificity of VIA for CIN2+ were 36.4% [95% confidence interval (CI): 15.2-64.6%] and 90.4% (95% CI: 85.4-93.7%), respectively. Sensitivity of self-HPV [100.0% (95% CI: 79.6-100.0%)] was 66% higher than that of sequential testing [33.3% (95% CI: 15.2-58.3%)]. Meanwhile, specificity of self-HPV [74.5% (95% CI: 70.6-78.1%)] was 22% lower than that of sequential testing [96.7% (95% CI: 94.8-97.9%)]. A two-stage screening strategy with self-HPV followed by VIA improves specificity of cervical cancer screening, but at the cost of an important loss of sensitivity. Ways to improve VIA performance or other tools are needed to increase positive predictive value of HPV testing.
世界卫生组织最近提倡采用两步策略，即用人乳头瘤病毒（HPV）检测，然后用醋酸（VIA）对宫颈进行目视检查，作为宫颈癌筛查的合适选择。然而，其在初级筛查中的准确性从未得到过直接评估。为了评估在低收入环境中自我采集标本（自我 HPV）后进行 VIA（顺序检测）对 HPV 检测的有效性，我们在喀麦隆的两个城市周边地区招募了 540 名年龄在 30 至 65 岁之间的女性。对符合条件的女性进行了有关宫颈癌和自我采样的咨询。HPV 阳性和 HPV 阴性的随机样本的女性被召回进行 VIA 和活检。疾病的定义是根据宫颈上皮内瘤变 2 级或更高级别（CIN2+）的解释。在调整验证偏差后，确定了 VIA、自我 HPV 和顺序检测的性能。HPV 患病率为 27.0%。VIA 阳性率为 12.9%，疾病患病率为 5%。VIA 对 CIN2+的敏感性和特异性分别为 36.4%（95%置信区间：15.2-64.6%）和 90.4%（95%置信区间：85.4-93.7%）。自我 HPV 的敏感性[100.0%（95%置信区间：79.6-100.0%）]比顺序检测[33.3%（95%置信区间：15.2-58.3%）]高 66%。同时，自我 HPV 的特异性[74.5%（95%置信区间：70.6-78.1%）]比顺序检测[96.7%（95%置信区间：94.8-97.9%）]低 22%。两步筛查策略，即自我 HPV 检测后再进行 VIA 检测，提高了宫颈癌筛查的特异性，但代价是敏感性的显著下降。需要改进 VIA 性能或其他工具，以提高 HPV 检测的阳性预测值。
