Cancer Epidemiology Unit-CERMS, University of Turin, Turin, Italy.
J Clin Microbiol. 2013 Sep;51(9):2901-7. doi: 10.1128/JCM.01047-13. Epub 2013 Jun 26.
The Hybrid Capture 2 (HC2) test targets 13 human papillomavirus (HPV) types. Here, cross-reactivity with non-HC2-targeted HPV types is described. We aimed to define the proportion of HC2-positive women who had negative results with HC2-targeted HPV types and estimate its determinants and impact on women's health management. The New Technologies for Cervical Cancer (NTCC) trial was followed in two predetermined phases. Women in the experimental arm were tested for the presence of HPV DNA by HC2 following a sample collection in PreservCyt (first phase) or Digene specimen transport medium (STM) (second phase). HPV genotyping was performed on DNA samples from HC2-positive women by PCR with GP5(+)/GP6(+) primers and reverse line blot (RLB) hybridization. Untyped samples were submitted to direct sequencing or restriction fragment length polymorphism. Multivariate logistic regression analysis estimated the adjusted odds ratios (ORs) between the presence of HC2-targeted types and age, viral load, and type of transport medium. Out of 2,920 HC2-positive samples, 2,310 (79.1%) were positive on RLB for HC2-targeted types, 396 were positive (13.6%) for only non-HC2-targeted types (mostly represented by HPV-53, HPV-66, and HPV-70), and in 214 (7.33%) samples, no HPV types were detected. The probability of detecting HC2-targeted types increased with increasing viral load expressed as the relative light unit/positive-control specimen ratio (RLU/PC) (OR for unitary increase of log RLU/PC, 1.35; 95% confidence interval [CI], 1.30 to 1.42) and with STM versus PreservCyt (OR, 1.56; 95% CI, 1.25 to 1.84). If only the samples containing HC2-targeted types tested positive, the positive predictive value (PPV) would have increased from 7.0% (95% CI, 6.1% to 8.0%) to 8.4% (95% CI, 7.3 to 9.6), although 4.9% (95% CI, 2.4% to 8.8%) of cervical intraepithelial neoplasia grade 2(+) (CIN2(+)) cases would have been missed. In conclusion, STM use and an increased cutoff would reduce the HC2 analytical false-positive rate and increase the positive predictive value for high-grade CIN. The gain in clinical sensitivity by detecting non-HC2-targeted HPV types is limited.
杂交捕获 2 （HC2）测试针对 13 种人类乳头瘤病毒（HPV）类型。在这里，描述了与非 HC2 靶向 HPV 类型的交叉反应。我们旨在确定 HC2 阳性妇女中 HC2 靶向 HPV 类型阴性结果的比例，并估计其决定因素及其对妇女健康管理的影响。新的宫颈癌技术（NTCC）试验在两个预定阶段进行了随访。实验组妇女在 PreservCyt （第一阶段）或 Digene 标本运输培养基（STM）（第二阶段）采集样本后，通过 HC2 检测 HPV DNA 的存在。对 HC2 阳性妇女的 DNA 样本进行 HPV 基因分型，采用 GP5（+）/GP6（+）引物和反向线杂交（RLB）进行 PCR。未分型的样本进行直接测序或限制性片段长度多态性分析。多变量逻辑回归分析估计了 HC2 靶向类型与年龄、病毒载量和运输培养基类型之间存在的调整后比值比（OR）。在 2920 份 HC2 阳性样本中，2310 份（79.1%）RLB 检测到 HC2 靶向类型阳性，396 份（13.6%）仅检测到非 HC2 靶向类型阳性（主要由 HPV-53、HPV-66 和 HPV-70 代表），214 份（7.33%）样本未检测到 HPV 类型。检测到 HC2 靶向类型的概率随着病毒载量的增加而增加，以相对光单位/阳性对照标本比值（RLU/PC）表示（单位增加的对数 RLU/PC 的比值，1.35；95%置信区间[CI]，1.30 至 1.42）和 STM 与 PreservCyt（OR，1.56；95%CI，1.25 至 1.84）。如果仅包含 HC2 靶向类型的样本检测为阳性，则阳性预测值（PPV）将从 7.0%（95%CI，6.1%至 8.0%）增加到 8.4%（95%CI，7.3%至 9.6%），尽管会错过 4.9%（95%CI，2.4%至 8.8%）的宫颈上皮内瘤变 2+（CIN2+）病例。总之，使用 STM 和增加截止值将降低 HC2 的分析假阳性率，并增加高级别 CIN 的阳性预测值。通过检测非 HC2 靶向 HPV 类型获得的临床敏感性增益有限。
