Varl Jerneja, Ivanus Urska, Marinsek Ziva Pohar, Jerman Tine, Valencak Anja Ostrbenk, Poljak Mario, Prevodnik Veronika Kloboves
Department of Experimental Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia.
University of Ljubljana, Faculty of Medicine, Ljubljana, Slovenia.
Radiol Oncol. 2019 Sep 24;53(3):316-322. doi: 10.2478/raon-2019-0044.
Background The Hybrid Capture 2 (HC2) High-Risk HPV DNA assay serves as a triage test in the Slovenian national cervical cancer screening programme ZORA. To improve the limited analytical accuracy of HC2 test results near the cut-off value (1.0 relative light units/cut-off (RLU/CO)), we follow an internal protocol of repeating the test on all samples with borderline results within the 0.7-2.0 RLU/CO interval. The aim of the study was (i) to determine the clinical relevance of HC2 test results within three different "grey zones" for samples stored in Specimen Transport Medium (STM) and (ii) to determine whether the current algorithm of retesting "grey zone" STM specimens with the HC2 assay is clinically relevant. Patients and methods The study included 594 women between 20 and 65 years of age. All participating women were referred for colposcopy, and in cases of abnormal results, biopsy was performed. We assessed the distribution of HC2 test results and the corresponding proportion of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) lesions in three different "grey zones" (1.0-2.5, 0.4-4.0 and 0.7-2.0 RLU/CO), retested specimens with results within a 0.4-4.0 RLU/CO interval and calculated the sensitivity and specificity for HC2 at different RLU/CO values. Results The proportion of specimens within 1.0-2.5, 0.4-4.0 and 0.7-2.0 RLU/CO intervals was 3.9%, 10.8% and 4.5%, respectively. The proportion of CIN2+ lesions within these "grey zones" was 2.5%, 5.6% and 1.2%, respectively. Retesting the samples did not detect any additional CIN2+ cases. Within the 1.0-2.5 RLU/CO interval, the sensitivity decreased from 93.8% to 91.4%, while the specificity increased from 63.3% to 67.5%; for the 0.4-4.0 RLU/CO interval, the sensitivity decreased from 95.1% to 89.5%, while the specificity increased from 56.8% to 69.4%; and for the 0.7-2.0 RLU/CO interval, the sensitivity remained nearly constant (94.4 vs. 93.2%), while the specificity increased from 60.6% to 66.4%. Conclusions Our results show that retesting STM samples within the "grey zones" is not necessary. Retesting samples in the negative "grey zone" does not increase sensitivity, and retesting in the positive "grey zone" is not followed by a less intensive management of women, since these women are recalled regardless of the results of the retest. Furthermore, the majority of samples retain the original HC2 results after retest, and the number of CIN2+ lesions among women with "grey zone" HC2 results is low.
杂交捕获2（HC2）高危型人乳头瘤病毒（HPV）DNA检测在斯洛文尼亚国家宫颈癌筛查项目ZORA中用作分流检测。为提高HC2检测结果在临界值（1.0相对光单位/临界值（RLU/CO））附近有限的分析准确性，我们遵循一项内部方案，对所有结果在0.7 - 2.0 RLU/CO区间内的临界样本重复进行检测。本研究的目的是：（i）确定储存在样本运输介质（STM）中的样本在三个不同“灰色区域”内HC2检测结果的临床相关性；（ii）确定目前用HC2检测对“灰色区域”STM样本进行重新检测的算法是否具有临床相关性。
本研究纳入了594名年龄在20至65岁之间的女性。所有参与研究的女性均被转诊进行阴道镜检查，结果异常者进行活检。我们评估了HC2检测结果的分布情况以及在三个不同“灰色区域”（1.0 - 2.5、0.4 - 4.0和0.7 - 2.0 RLU/CO）中宫颈上皮内瘤变2级或更严重病变（CIN2 +）的相应比例，对结果在0.4 - 4.0 RLU/CO区间内的样本进行重新检测，并计算不同RLU/CO值下HC2的敏感性和特异性。
结果在1.0 - 2.5、0.4 - 4.0和0.7 - 2.0 RLU/CO区间内的样本比例分别为3.9%、10.8%和4.5%。这些“灰色区域”内CIN2 +病变的比例分别为2.5%、5.6%和1.2%。对样本进行重新检测未发现任何额外的CIN2 +病例。在1.0 - 2.5 RLU/CO区间内，敏感性从93.8%降至91.4%，而特异性从63.3%升至67.5%；在0.4 - 4.0 RLU/CO区间内，敏感性从95.1%降至89.5%，而特异性从56.8%升至69.4%；在0.7 - 2.0 RLU/CO区间内，敏感性几乎保持不变（94.4%对93.2%），而特异性从60.6%升至66.4%。
我们的结果表明，对“灰色区域”内的STM样本进行重新检测没有必要。对阴性“灰色区域”的样本进行重新检测不会提高敏感性，而对阳性“灰色区域”的样本进行重新检测后，女性并不会接受强度较低的管理，因为无论重新检测结果如何，这些女性都会被召回。此外，大多数样本重新检测后仍保留原来的HC2结果，且HC2结果处于“灰色区域”的女性中CIN2 +病变的数量较少。
