University of Szeged, Faculty of Medicine, Department of Pathology, Allomás u. 2., H-6720 Szeged, Hungary.
J Clin Pathol. 2012 Mar;65(3):193-9. doi: 10.1136/jclinpath-2011-200301. Epub 2011 Nov 16.
One-step nucleic acid amplification (OSNA) is a novel method introduced for the lymph node staging of breast cancer and has been tested in multiple series. The present review summarises current literature and concerns related to the new method. The results of this automated molecular assay based on the quantification of cytokeratin 19 mRNA show a 96% concordance rate with detailed histopathology complemented with immunohistochemistry when alternative slices of the same lymph node are used for the two tests. The low false-negative rate makes OSNA suitable for the intraoperative evaluation of sentinel lymph nodes. The false-positive rate also seems very low. Most discordant cases are explainable by low volume metastases (micrometastases), which may be missing from the material submitted for one test, but not from the different part used for the other test. It is tempting to change the gold standard for comparisons between the methods, and if this is done, histology seems to come out as a weaker test for the identification of metastases. OSNA detects more low volume nodal involvement, but it is uncertain whether these require further axillary treatment, and this will be a subject for future investigations. Therefore, it is also uncertain whether the advantage of OSNA of detecting practically all metastases due to complete sampling of lymph node tissue is clinically more important than the exclusion of metastases greater than micrometastasis that can be reliably done by intraoperative microscopy followed by permanent section histology.
一步法核酸扩增（OSNA）是一种新方法，用于乳腺癌淋巴结分期，已在多项系列研究中进行了测试。本综述总结了当前与这种新方法相关的文献和关注点。基于细胞角蛋白 19 mRNA 定量的这种自动化分子检测的结果，当同一淋巴结的不同切片用于两种检测时，与补充免疫组织化学的详细组织病理学检查具有 96%的一致性率。该检测的假阴性率较低，使其适用于前哨淋巴结的术中评估。假阳性率似乎也非常低。大多数不一致的病例可通过低体积转移（微转移）来解释，这些微转移可能会从一种检测方法提交的材料中丢失，但不会从另一种检测方法使用的不同部分中丢失。改变方法之间比较的金标准是很诱人的，如果这样做，组织学似乎成为一种更弱的检测转移的方法。OSNA 检测到更多的低体积淋巴结受累，但尚不确定这些是否需要进一步的腋窝治疗，这将是未来研究的主题。因此，由于完整地对淋巴结组织进行采样，OSNA 检测到几乎所有转移的优势是否比术中显微镜检查加永久性切片组织学可靠地排除微转移以上的转移更具有临床重要性也尚不确定。
