根据确证检测方法，游离 DNA 筛查性染色体异常的确认率。

Confirmation rate of cell free DNA screening for sex chromosomal abnormalities according to the method of confirmatory testing.

机构信息

Cenata GmbH, Tübingen, Germany.

Research and Development, Cytogenetics and Medical Genetics Unit, TOMA Advanced Biomedical Assays S.p.A., Impact Lab Group, Busto Arsizio, Italy.

出版信息

Prenat Diagn. 2021 Sep;41(10):1258-1263. doi: 10.1002/pd.5814. Epub 2020 Sep 2.

DOI:10.1002/pd.5814

PMID:32804406

Abstract

OBJECTIVE

To examine the positive predictive value (PPV) of cfDNA screening for sex chromosome aneuploidies (SCA) in a large series of over 90 000 patients.

METHODS

Retrospective study based on samples that were sent to Cenata, a private laboratory which uses the Harmony Prenatal Test. The SCA high-risk results were stratified according to the method of diagnostic testing and according to karyotype result.

RESULTS

The study population consisted of 144 cases. The CfDNA test indicated monosomy X, XXX, XXY, and XYY in 62, 37, 40, and 5 cases, respectively. The overall PPV was 38.9% (30.9-47.4), 29.0% (18.2-42.9) for monosomy X, 29.7% (15.9-47.9) for 47,XXX, 57.5% (40.9-73.0) for 47,XXY, and 80.0% (28.4-99.5) for 47,XYY). A total of 112 (77.8%) women with a high-risk result for SCAs opted for prenatal karyotyping. In this group, there were significant differences in the PPV if the karyotype was assessed by amniocentesis or by CVS: 29.5% vs 50.0%. This significant difference was driven by the monosomy X result which shows a significantly higher PPV in CVS (54.6% (23.4-83.3) vs 17.1% (6.6-33.6)). For the other SCAs, the differences were not significant.

CONCLUSION

PPV of an abnormal cfDNA test for SCAs is low, particularly for monosomy X. The confirmation rate depends on the type of confirmatory test.

摘要

目的

在超过 90,000 例患者的大型系列中，检查 cfDNA 筛查性染色体非整倍体（SCA）的阳性预测值（PPV）。

方法

基于送往 Cenata 的样本进行的回顾性研究，Cenata 是一家私人实验室，使用 Harmony 产前测试。根据诊断测试方法和核型结果对 SCA 高风险结果进行分层。

结果

研究人群包括 144 例。CfDNA 测试分别指示单体 X、XXX、XXY 和 XYY 的病例数为 62、37、40 和 5 例。总体 PPV 为 38.9%（30.9-47.4），单体 X 为 29.0%（18.2-42.9），47,XXX 为 29.7%（15.9-47.9），47,XXY 为 57.5%（40.9-73.0），47,XYY 为 80.0%（28.4-99.5）。共有 112 名（77.8%）SCAs 高风险结果的女性选择进行产前核型分析。在这组中，如果通过羊膜穿刺术或 CVS 评估核型，PPV 有显著差异：29.5%与 50.0%。这种显著差异是由单体 X 结果驱动的，CVS 中的单体 X 结果显示出显著更高的 PPV（54.6%（23.4-83.3）与 17.1%（6.6-33.6））。对于其他 SCA，差异不显著。