Fluorodeoxyglucose versus Choline Positron Emission Tomography/Computed Tomography Response Evaluation in Two Malignant Pleural Mesothelioma Patients Treated with Talc Pleurodesis and Neoadjuvant Chemotherapy

Talc pleurodesis has been reported to increase fluorodeoxyglucose (FDG) uptake in the high attenuation areas of pleural thickening, making it difficult to distinguish between benign granulomatous inflammatory processes and malignancies, which may therefore interfere with the post-chemotherapy disease evaluation on FDG-positron emission tomography/computed tomography (PET/CT). We present two cases of malignant pleural mesothelioma treated with talc pleurodesis and neoadjuvant chemotherapy (NAC) before pleurectomy/decortication in which post-NAC FDG-PET/CT showed intense FDG uptakes in the high attenuation areas of pleural thickening with false positive result, whereas post-NAC (11)C-choline PET/CT showed mild choline uptake of pleural talc deposit, which did not interfere with the post-chemotherapy disease evaluation. Thus we suggest choline-PET/CT may show little choline uptake to granulomatous inflammation and evaluate treatment response in malignant pleural mesothelioma patients treated with talc pleurodesis and NAC.