Association of PET/CT and VATS findings with histology analysis in the study of pleural effusions.

Introduction: Histological analysis of the pleura obtained by video-assisted thoracoscopic surgery (VATS) is the best diagnostic technique in the study of neoplastic pleural effusions. This study evaluates the relationship between Positron Emission Tomography (PET)/Computed Tomography (CT) and VATS findings, the result of the first pleural biopsy, and the final diagnosis of malignancy or non-malignancy.

Methods: Prospective study of consecutive patients with pleural effusions undergoing PET/CT and VATS from October 2013 to December 2023. The following variables were recorded: PET/CT score (nodular pleural thickening, pleural nodules with standardized uptake value (SUV) > 7.5, lung mass or extra pleural malignancy, mammary lymph node with SUV > 4.5 and cardiomegaly); VATS data (drained volume, visceral and parietal pleural thickening, nodules or masses, septa, plaques, fluid appearance, trapped lung, and suspected diagnosis of the procedure), as well as the histological study of the first pleural biopsy (benign or malignant) and the final diagnosis of benign or malignant pleural effusion. A logistic regression study of the variables was performed.

Results: 95.8% of the patients with PET/CT and pleuroscopy not suggestive of malignancy had non-malignant histological findings, while 93.2% of the patients with PET/CT and pleuroscopy suggestive of malignancy had malignant histological findings. PET/CT, pleuroscopy, and the result of the first pleural biopsy showed a significant association with the final diagnosis of pleural effusion.

Conclusions: There is a strong association between PET/CT findings, VATS and pleural histology.