EVALUATION OF PTGER4 GENE METHYLATION IN PLASMA FOR LUNG CANCER DETECTION

Objectives: To evaluate the diagnostic value of PTGER4 (Prostaglandin E Receptor 4) gene methylation in plasma for lung cancer detection compared to healthy controls. Methods: A cross-sectional, case-control study was conducted on 149 non-small cell lung cancer (NSCLC) patients and 100 healthy individuals. Peripheral blood samples were collected for PTGER4 methylation analysis using real-time methylation-specific PCR (MSP). Data were analyzed using SPSS 26.0, including group comparisons, receiver operating characteristic (ROC) analysis, and logistic regression. Results: The PTGER4 methylation positivity rate was significantly higher in lung cancer patients (18.8%) compared to healthy controls (3.0%, p < 0.001). PTGER4 methylation positivity increased the risk of lung cancer by 6.3 times (OR = 6.30; 95%CI: 1.90 - 20.40). The area under the ROC curve (AUC) was 0.58, with a sensitivity of 18.8% and a specificity of 97.0%. Conclusion: PTGER4 gene methylation is a promising biomarker for lung cancer detection. Despite its limited sensitivity, the high specificity suggests its potential as a confirmatory diagnostic tool, particularly when combined with imaging modalities such as low-dose computed tomography (LDCT).