An initial study on the comparison of diagnostic performance of 18F-FDG PET/MR and 18F-FDG PET/CT for thoracic staging of non-small cell lung cancer: Focus on pleural invasion

Objective: To compare the diagnostic performance of 18F-FDG PET/MR and PET/CT preliminarily for the thoracic staging of non-small cell lung cancer (NSCLC) with a special focus on pleural invasion evaluation.Methods: Fifty-two patients with pathologically confirmed NSCLC were included and followed for another year. Whole-body 18F-FDG PET/CT and subsequent thoracic PET/MR were performed for initial thoracic staging. Thoracic (simultaneous) PET/MR acquired PET images and MRI sequences including T2 weighted imaging, with and without fat saturation, T1 weighted imaging, and diffusion weighted imaging. Two radiologists independently assessed the thoracic T, N staging and pleural involvement. The McNemar Chi-square test was used to compare the differences between PET/CT and PET/MR in the criteria. The area under the receiver-operating-characteristic curves (AUC) was calculated.Results: Compared to PET/CT, PET/MR exhibited higher sensitivity, specificity in the detection of pleural invasion; 82% vs. 64% (P = .625), 98% vs. 95% (P = 1.000), PET/MR to PET/CT, respectively. The receiver-operating-characteristic analysis results of PET/CT vs. PET/MR for the pleural invasion were as follow: AUCPET/CT = 0.79, AUCPET/MR = 0.90, P = .21. Both T staging results and N staging results were approximately identical in PET/CT and PET/MR. Differences between PET/CT and PET/MR in T staging, N staging as well as pleural invasion accuracy were not statistically significant (P > .05, each).Conclusion: PET/MR and PET/CT demonstrated equivalent performance about the evaluation of preopera-tive thoracic staging of NSCLC patients. PET/MR may have greater potential in pleural invasion evaluation for NSCLC, especially for solid nodules, crucial to clinical decision-making, though our results did not demonstrate statistical significance.& COPY; 2022 Published by Elsevier Espana, S.L.U. on behalf of Sociedad Espanola de Medicina Nuclear e Imagen Molecular.