Objective:

To explore the clinical role of 18 F-FDG PET/CT in distinguishing malignant from benign pleural effusion in pretreatment non-small cell lung cancer (NSCLC) patients.

Methods:

The NSCLC patients with pleural effusion who underwent PET/CT were retrospectively reviewed. Malignant or benign pleural effusion was confirmed with thoracentesis or biopsy. When the standard uptake value (SUV) of pleural was h

igher than 2.5 (SUV＞2.5) or pleural activity was higher than mediastinal background (pleural SUV＞aorta SUV)

pleural effusion was diagnosed as malignant. The sensitivity

specificity

positive predictive value

negative predictive value

and accuracy of PET/CT for detecting malignant pleural metastases were calculated.

Results:

Forty- six patients were enrolled

and 39 were malignant. For SUV＞2.5

the sensitivity

specificity

positive predictive value

negative predictive value

and accuracy of PET/CT were 76.9%

100.0%

100.0%

43.8%

and 80.4%; and 89.7%

100.0%

100.0%

63.6% and 91.3% for pleural SUV＞aorta SUV

respectively. The areas under curve of receiver operating characteristic (ROC) curve were 0.961 and 0.972

respectively.

Conclusion:

18 F-FDG PET/CT can play a significant role in distinguishing malignant from benign pleural effusion in pretreatment NSCLC patients. The diagnostic accuracy could be improved when pleural activity higher than mediastinal background that used as diagnostic criteria.