Cha Su-Na, Niu Yan, Wen Jian-Xun, Yan Cheng, Yang Qian, Zhu Hong-Zhe, Lin Xi, Cao Xi-Shan, Gao Wen-Hui, Wang Ya-Fei, Zhou Feng, Yan Li, Zheng Wen-Qi, Hu Zhi-De
Department of Laboratory Medicine, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China.
Key Laboratory for Biomarkers, Inner Mongolia Medical University, Hohhot, China.
Transl Lung Cancer Res. 2024 May 31;13(5):1061-1068. doi: 10.21037/tlcr-24-68. Epub 2024 May 29.
Serum carbohydrate antigen 50 (CA50) is an auxiliary diagnostic marker for various solid tumors, but it remains unclear whether CA50 in pleural fluid can assist in the diagnosis of malignant pleural effusion (MPE). This study aimed to evaluate the diagnostic accuracy of pleural fluid CA50 for MPE in pleural effusion patients with undetermined causes.
This study prospectively recruited pleural effusion patients with undetermined causes who visited the Affiliated Hospital of Inner Mongolia Medical University between September 2018 and July 2021. We measured pleural fluid CA50 level with an electrochemiluminescence assay. We analyzed the diagnostic accuracy of CA50 and carcinoembryonic antigen (CEA) for MPE with the receiver operating characteristic (ROC) curve. The net benefits of CA50 and CEA were analyzed using the decision curve analysis (DCA).
We enrolled 66 MPEs and 87 benign pleural effusions (BPEs). MPE patients had significantly higher CA50 and CEA than BPE patients. The area under the ROC curve (AUC) of CA50 was 0.72 (95% CI: 0.63-0.80). CA50 had a sensitivity of 0.30 (95% CI: 0.19-0.41) and a specificity of 1.00 (95% CI: 1.00-1.00) at the threshold of 15 IU/mL. The decision curve of CA50 was above the reference line at the calculated risk probability of between 0.30 and 1.00. Venn diagram indicated that some patients with low CEA (<50 or <150 ng/mL) and/or negative cytology can be identified by positive CA50 (>15 IU/mL).
Pleural fluid CA50 has moderate accuracy and net benefit for detecting MPE. CA50 >15 IU/mL can be used to diagnose MPE. The combination of CA50 and CEA improves the diagnostic sensitivity for MPE.
血清糖类抗原50（CA50）是多种实体肿瘤的辅助诊断标志物，但胸腔积液中的CA50能否协助诊断恶性胸腔积液（MPE）尚不清楚。本研究旨在评估胸腔积液CA50对病因不明的胸腔积液患者MPE的诊断准确性。
本研究前瞻性纳入了2018年9月至2021年7月期间就诊于内蒙古医科大学附属医院的病因不明的胸腔积液患者。我们采用电化学发光法检测胸腔积液CA50水平。我们用受试者工作特征（ROC）曲线分析CA50和癌胚抗原（CEA）对MPE的诊断准确性。使用决策曲线分析（DCA）分析CA50和CEA的净效益。
我们纳入了66例MPE患者和87例良性胸腔积液（BPE）患者。MPE患者的CA50和CEA显著高于BPE患者。CA50的ROC曲线下面积（AUC）为0.72（95%CI：0.63-0.80）。在阈值为15 IU/mL时，CA50的灵敏度为0.30（95%CI：0.19-0.41），特异性为1.00（95%CI：1.00-1.00）。在计算出的风险概率为0.30至1.00之间时，CA50的决策曲线高于参考线。维恩图表明，一些CEA低（<50或<150 ng/mL）和/或细胞学阴性的患者可通过CA50阳性（>15 IU/mL）来识别。
