Translational Research Program, Department of Pathology, Dartmouth Medical School, Dartmouth Hitchcock Medical Center and Norris Cotton Cancer Center, Lebanon, NH 03756, USA.
Exp Mol Pathol. 2010 Feb;88(1):1-6. doi: 10.1016/j.yexmp.2009.10.004. Epub 2009 Oct 17.
Sentinel lymph node (SLN) processing remains variable in terms of performing multiple tissue levels and immunohistochemical (IHC) or PCR-based assays. A rapid and reliable molecular pathology assay, as an adjunct to routine SLN processing, could minimize and standardize the histologic evaluation needed for an accurate and clinically significant diagnosis. We compared the recently FDA-approved Veridex GeneSearch Breast Lymph Node (BLN) Assay (Veridex, LLC; Warren, NJ), a real time reverse transcriptase-polymerase chain reaction assay that is designed to detect metastases >0.2 mm, with our standard lymph node processing.
The GeneSearch BLN assay evaluates RNA expression data for three target genes (mammaglobin, cytokeratin 19, and internal control porphobilinogen deaminase), and provides a qualitative (positive/negative) result. In 59 patients, the assay was performed on SLN tissue that would normally be deep within the tissue block and not routinely evaluated histologically. Two 1 -mm slices from the outer node portions were submitted fresh for RNA extraction; the remaining tissue was submitted for routine histology.
Of the 59 patients, the assay determined 43 as true negative, eight as true positive, one as false-negative, three as false-positive, and four as invalid. Assay sensitivity was 88.9%, specificity 93.5%.
The sensitivity of the assay sampling from the outer node tissue was high (88.9%) and identical to that validated in the large registration study in which half of the node was assessed as alternate slices (87.6%). Our protocol uses this assay as an adjunct to traditional histologic evaluation, to reduce and standardize the number of tissue sections needed for thorough SLN evaluation, and to enhance our ability to bank RNA.
前哨淋巴结 (SLN) 的处理在进行多个组织层面的检测以及免疫组织化学 (IHC) 或基于聚合酶链反应 (PCR) 的检测方面存在差异。作为常规 SLN 处理的辅助手段，一种快速可靠的分子病理学检测方法可以最大限度地减少并标准化准确且具有临床意义的诊断所需的组织学评估。我们比较了最近获得 FDA 批准的 Veridex GeneSearch 乳腺淋巴结 (BLN) 检测 (Veridex, LLC; Warren, NJ)，这是一种实时逆转录聚合酶链反应检测方法，旨在检测 >0.2mm 的转移灶，以及我们的标准淋巴结处理方法。
GeneSearch BLN 检测评估三个靶基因 (乳球蛋白、细胞角蛋白 19 和内参卟啉原脱氨酶) 的 RNA 表达数据，并提供定性 (阳性/阴性) 结果。在 59 例患者中，该检测方法在 SLN 组织上进行，该组织通常位于组织块的深处，不会常规进行组织学评估。从外节点部分的两个 1mm 切片新鲜提交进行 RNA 提取；其余组织提交进行常规组织学检查。
在 59 例患者中，检测结果确定 43 例为真阴性，8 例为真阳性，1 例为假阴性，3 例为假阳性，4 例为无效。检测的敏感性为 88.9%，特异性为 93.5%。
从外节点组织取样的检测敏感性很高 (88.9%)，与在其中一半节点作为替代切片进行评估的大型注册研究中验证的敏感性相同 (87.6%)。我们的方案将该检测方法作为传统组织学评估的辅助手段，以减少和标准化彻底评估 SLN 所需的组织切片数量，并增强我们储存 RNA 的能力。
