Haldorsen Tor, Skare Gry Baadstrand, Ursin Giske, Bjørge Tone
Department of Research, Cancer Registry of Norway , Oslo , Norway.
Acta Oncol. 2015 Feb;54(2):200-9. doi: 10.3109/0284186X.2014.932433. Epub 2014 Jun 24.
High-risk human papilloma virus (hrHPV) testing was added to the cytology triage of women with equivocal screening smears in the Norwegian programme for cervical cancer screening in 2005. In this population-based observational before and after study we assessed the effect of changing the screening algorithm.
In periods before and after the change 75 852 and 66 616 women, respectively, were eligible for triage, i.e. they had smear results of unsatisfactory, atypical squamous cells of undetermined significance (ASC-US), or low-grade squamous intraepithelial lesion (LSIL) at routine screening. The triage was delayed as supplementary testing started six months after the initial screening. The groups were compared with respect to results of triage and later three-year cumulative incidence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+).
Before and after the change in the screening algorithm 5.2% (3964/75 852) and 8.1% (5417/66 616) of women, respectively, were referred to colposcopy. Among women referred to colposcopy cumulative incidence of CIN2+ (positive predictive value of referral) increased from 42.0% [95% confidence interval (CI): 40.3 - 43.7%] in the period with cytology only to 48.0% (95% CI 46.6 - 49.4%) after the start of HPV testing. For women recalled to ordinary screening the three-year cumulative incidence decreased from 2.7% (95% CI 2.5 - 2.9%) to 1.0% (95% CI 0.9 - 1.2%) during the same period. Among women with LSIL at routine screening and HPV testing in triage, 52.5% (1976/3766) were HPV positive.
The new algorithm with HPV testing implemented in 2005 resulted in an increased rate of referral to colposcopy, but in a better risk stratification with respect to precancerous disease.
2005年，在挪威宫颈癌筛查项目中，高危型人乳头瘤病毒（hrHPV）检测被纳入到对筛查涂片结果不明确的女性进行细胞学分流的流程中。在这项基于人群的前后对照观察性研究中，我们评估了改变筛查算法的效果。
在改变筛查算法之前和之后的时期，分别有75852名和66616名女性符合分流条件，即在常规筛查中她们的涂片结果为不满意、意义不明确的非典型鳞状细胞（ASC-US）或低级别鳞状上皮内病变（LSIL）。由于补充检测在初次筛查六个月后开始，分流被推迟。比较两组的分流结果以及随后三年宫颈上皮内瘤变2级或更高级别（CIN2+）的累积发病率。
在筛查算法改变之前和之后，分别有5.2%（3964/75852）和8.1%（5417/66616）的女性被转诊至阴道镜检查。在被转诊至阴道镜检查的女性中，CIN2+的累积发病率（转诊的阳性预测值）从仅进行细胞学检查时期的42.0%[95%置信区间（CI）：40.3 - 43.7%]增加到开始HPV检测后的48.0%（95%CI 46.6 - 49.4%）。同期，被召回进行常规筛查的女性三年累积发病率从2.7%（95%CI 2.5 - 2.9%）降至1.0%（95%CI 0.9 - 1.2%）。在常规筛查为LSIL且分流时进行HPV检测的女性中，52.5%（1976/3766）为HPV阳性。
2005年实施的包含HPV检测的新算法导致转诊至阴道镜检查的比例增加，但在癌前疾病方面实现了更好的风险分层。
