Preoperative staging of mesothelioma by 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography fused imaging and mediastinoscopy compared to pathological findings after extrapleural pneumonectomy.

OBJECTIVES Extrapleural pneumonectomy (EPP) in MPM may be confined with both morbidity and mortality and careful preoperative staging identifying resectable patients is important. Staging is difficult and the accuracy of preoperative CT scan, 18F-FDG PET/CT scan (PET/CT), and mediastinoscopy is unclear. The objectives were to compare these staging techniques to each other and to surgical-pathological findings. METHODS Patients had epithelial subtype MPM, age <or=70 years, and lung function test allowing pneumonectomy. Preoperative staging after 3-6 courses of induction chemotherapy included conventional CT scan, PET/CT, and mediastinoscopy. Surgical-pathological findings were compared to preoperative findings. RESULTS Forty-two consecutive patients were without T4 or M on CT scan. PET/CT showed inoperability in 12 patients (29%) due to T4 (7 patients) and M1 (7 patients). Among 30 patients with subsequent mediastinoscopy, including 10 with N2/N3 on PET/CT, N2 were histologically verified in 6 (20%). Among 24 resected patients, T4 occurred in 2 patients (8%), and N2 in 4 (17%), all being PET/CT negative. PET/CT accuracy of T4 and N2/N3 compared to combined histological results of mediastinoscopy and EPP showed sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios of 78% and 50%, 100% and 75%, 100% and 50%, 94% and 75%, not applicable and 5.0, and 0.22 and 0.67, respectively. CONCLUSIONS Non-curative surgery is avoided in 29% out of 42 MPM patients by preoperative PET/CT and in further 14% by mediastinoscopy. Even though both procedures are valuable, there are false negative findings with both, urging for even more accurate staging procedures.