Sang Min Lee, Abstract Co-Author: Nothing to Disclose

Jin Mo Goo MD, PhD, Presenter: Research Grant, Guerbet SA

Chang Min Park MD, PhD, Abstract Co-Author: Nothing to Disclose

To compare the accuracy of PET/MR and PET/CT in the preoperative staging of non-small cell lung cancer (NSCLC).

Institutional review board approval and informed consent from patients were obtained. From March 2013 to February 2014, 50 patients (31 men and 19 women; mean age, 62.6 years ± 10.9; range 35-84 years) who had proven or radiologically suspected lung cancer which appeared to be resectable on chest CT were enrolled in this study. After exclusion of nine patients (histology other than NSCLC [n=4]; no surgical resection [n=5]), 41 patients were included in the analyses. PET/MR was performed for NSCLC staging followed by PET/CT on the same day. In terms of MR sequences, T1 coronal, T2 HASTE axial, pre- and post-contrast VIBE axial images were obtained in 5 to 6 bed positions, and DWI in two bed positions were obtained as well. Tumor stages were determined by using the TNM and American Joint Committee on Cancer staging systems. Observers (three radiologists and two nuclear medicine physicians) evaluated PET/MR and PET/CT separately and independently. The standard reference was pathologic results and extrathoracic metastases were confirmed pathologically or by follow-up imaging. The accuracies of PET/MR and PET/CT for NSCLC staging were compared by using the McNemar test.

The primary tumor stages (n=36 patients) were correctly diagnosed in 26 patients (72.2%) on PET/MR and in 26 patients (72.2%) on PET/CT (P=1.0). The node stages (n=39 patients) were correctly determined in 24 patients (61.5%) on PET/MR and in 22 patients (56.4%) on PET/CT (P=0.688). Metastatic lesions in the brain, bone, liver, and left pleura were detected in 4 patients (9.8%). PET/MR depicted all metastatic lesions while PET/CT missed solitary brain metastasis in one patient. The accuracies of overall stages were 53.7% (22/41) on PET/MR and 53.7% (22/41) on PET/CT. There were no significant differences in accuracies of overall stages between PET/MR and PET/CT (P=1.0).

PET/MR is comparable to PET/CT in the preoperative staging of NSCLC and has the potential to provide imaging exams for NSCLC staging workup at one time. 

Except for the advantage of reduced radiation dose and the potential of one-stop examination including brain evaluation, PET/MR does not appear to be superior to PET/CT in the staging of NSCLC. Therefore, streamlining of PET/MRI protocols may be necessary in this respect.

Lee, S, Goo, J, Park, C, Preoperative Staging of Non-small Cell Lung Cancer: Comparison of PET/MR and PET/CT.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14017560.html