Department of Pathology, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, The Netherlands.
Department of Molecular Pathology, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
Virchows Arch. 2019 Aug;475(2):191-199. doi: 10.1007/s00428-019-02595-9. Epub 2019 Jul 1.
Pre-analytical factors, such as fixation time, influence morphology of diagnostic and predictive immunohistochemical staining, which are increasingly used in the evaluation of lung cancer. Our aim was to investigate if variations in fixation time influence the outcome of immunohistochemical staining in lung cancer. From lung resections, specimen with tumor size bigger than 4 cm, 10 samples were obtained: 2 were put through the standard fixation protocol, 5 through the delayed, and 3 through the prolonged fixation protocol. After paraffin embedding, tissue microarrays (TMAs) were made. They were stained with 20 antibodies and scored for quality and intensity of staining. Samples with delay in fixation showed loss of TMA cores on glass slides and deterioration of tissue quality leading to reduction in the expression of CK 7, Keratin MNF116, CAM 5.2, CK 5/6, TTF-1, C-MET, Napsin A, D2-40, and PD-L1. Prolonged fixation had no influence on the performance of immunohistochemical stains. Delay of fixation negatively affects the expression of different immunohistochemical markers, influencing diagnostic (cytokeratins) and predictive (PD-L1) testing. These results emphasize the need for adequate fixation of resection specimen.
在分析前因素，如固定时间，影响形态学的诊断和预测免疫组织化学染色，这在肺癌的评估中越来越多地被使用。我们的目的是调查固定时间的变化是否会影响肺癌免疫组织化学染色的结果。从肺切除标本中，选取肿瘤大小大于 4cm 的标本 10 例，其中 2 例采用标准固定方案，5 例采用延迟固定方案，3 例采用延长固定方案。石蜡包埋后，制作组织微阵列（TMA）。用 20 种抗体对其进行染色，并对染色的质量和强度进行评分。固定延迟的样本在载玻片上失去 TMA 核心，组织质量恶化，导致 CK7、Keratin MNF116、CAM 5.2、CK 5/6、TTF-1、C-MET、Napsin A、D2-40 和 PD-L1 的表达减少。延长固定时间对免疫组织化学染色的性能没有影响。固定时间的延迟会对不同免疫组织化学标志物的表达产生负面影响，从而影响诊断（细胞角蛋白）和预测（PD-L1）检测。这些结果强调了充分固定切除标本的必要性。
