背景:细胞块(CB)广泛用于生物标志物分析,例如免疫染色。尽管福尔马林固定石蜡包埋组织的免疫组织化学是标准化的,细胞学有多种制备方法和固定剂。我们的目的是研究不同常用固定剂对转移性肺腺癌胸腔积液CBs免疫反应性的影响。
方法:这项前瞻性研究包括24例不同肺腺癌患者的恶性胸腔积液。从每个案例中,将四个相同的CB固定在10%中性缓冲的福尔马林中,PreservCyt,CytoLyt,和富含细胞的红(只有17例),分别。排除含有<100个恶性细胞的样品。所有CB均用甲状腺转录因子1(TTF-1;克隆8G7G3/1和SPT24)染色,napsinA,claudin4CEA,CK7和上皮细胞粘附分子(EpCAM;克隆BS14、Ber-Ep4和MOC-31)。评估染色细胞的分数和强度。
结果:在所研究的标记物中,TTF-1克隆8G7G3/1和EpCAM克隆MOC-31的染色比例显着差异,尤其是在CytoLyt中阴性的病例(33.3%和83.3%阳性,分别)和PreservCyt(62.5%和83.3%),而富含细胞的红(76.5%和94.1%)和福尔马林(均95.8%)呈阳性。与TTF-1克隆8G7G3/1,napsinA的福尔马林相比,所有基于酒精的固定剂的染色强度明显较弱,和EpCAM克隆MOC-31,而与福尔马林相比,EpCAM克隆Ber-Ep4仅在PreservCyt中明显更弱。
结论:免疫细胞化学表达和与福尔马林固定的CBs的一致性因使用的固定剂以及抗体和克隆而异,保证研究非福尔马林固定细胞学的每种生物标志物的可靠性。
BACKGROUND: Cell blocks (CBs) are widely used for biomarker analyses such as immunostaining. Although immunohistochemistry on
formalin-fixed paraffin-embedded tissues is standardized, there are multiple preparation methods and fixatives for cytology. Our objective was to investigate the effect of different common fixatives on the immunoreactivity of pleural effusion CBs with metastatic lung adenocarcinomas.
METHODS: This prospective study included 24 malignant pleural effusions from different patients with lung adenocarcinoma. From each case, four identical CBs were fixed in 10% neutral buffered
formalin, PreservCyt, CytoLyt, and CytoRich Red (only 17 of the cases), respectively. Samples containing <100 malignant cells were excluded. All CBs were stained with thyroid transcription factor 1 (TTF-1; clones 8G7G3/1 and SPT24), napsin A, claudin 4, CEA, CK7, and epithelial cell adhesion molecule (EpCAM; clones BS14, Ber-Ep4, and MOC-31). The fraction and intensity of stained cells were evaluated.
RESULTS: Of the investigated markers, a significant difference in staining proportion was seen for TTF-1 clone 8G7G3/1 and EpCAM clone MOC-31, especially with cases being negative in CytoLyt (33.3% and 83.3% positive, respectively) and PreservCyt (62.5% and 83.3%) whereas being positive in CytoRich Red (76.5% and 94.1%) and formalin (both 95.8%). A significantly weaker intensity of staining was seen for all alcohol-based fixatives compared to
formalin for TTF-1 clone 8G7G3/1, napsin A, and EpCAM clone MOC-31, whereas EpCAM clone Ber-Ep4 was significantly weaker only in PreservCyt compared with
formalin.
CONCLUSIONS: Immunocytochemical expression and concordance with
formalin-fixed CBs differ depending on the used fixative as well as the antibody and clone, warranting investigation of the reliability of each biomarker for non-formalin-fixed cytology.