PT - JOURNAL ARTICLE AU - Philipp Heusch AU - Christian Buchbender AU - Jens Köhler AU - Felix Nensa AU - Thomas Gauler AU - Benedikt Gomez AU - Henning Reis AU - Georgios Stamatis AU - Hilmar Kühl AU - Verena Hartung AU - Till A. Heusner TI - Thoracic Staging in Lung Cancer: Prospective Comparison of <sup>18</sup>F-FDG PET/MR Imaging and <sup>18</sup>F-FDG PET/CT AID - 10.2967/jnumed.113.129825 DP - 2014 Mar 01 TA - Journal of Nuclear Medicine PG - 373--378 VI - 55 IP - 3 4099 - http://jnm.snmjournals.org/content/55/3/373.short 4100 - http://jnm.snmjournals.org/content/55/3/373.full SO - J Nucl Med2014 Mar 01; 55 AB - Therapeutic decisions in non–small cell lung cancer (NSCLC) patients depend on the tumor stage. PET/CT with 18F-FDG is widely accepted as the diagnostic standard of care. The purpose of this study was to compare a dedicated pulmonary 18F-FDG PET/MR imaging protocol with 18F-FDG PET/CT for primary and locoregional lymph node staging in NSCLC patients using histopathology as the reference. Methods: Twenty-two patients (12 men, 10 women; mean age ± SD, 65.1 ± 9.1 y) with histopathologically confirmed NSCLC underwent 18F-FDG PET/CT, followed by 18F-FDG PET/MR imaging, including a dedicated pulmonary MR imaging protocol. T and N staging according to the seventh edition of the American Joint Committee on Cancer staging manual was performed by 2 readers in separate sessions for 18F-FDG PET/CT and PET/MR imaging, respectively. Results from histopathology were used as the standard of reference. The mean and maximum standardized uptake value (SUVmean and SUVmax, respectively) and maximum diameter of the primary tumor was measured and compared in 18F-FDG PET/CT and PET/MR imaging. Results: PET/MR imaging and 18F-FDG PET/CT agreed on T stages in 16 of 16 of patients (100%). All patients were correctly staged by 18F-FDG PET/CT and PET/MR (100%), compared with histopathology. There was no statistically significant difference between 18F-FDG PET/CT and 18F-FDG PET/MR imaging for lymph node metastases detection (P = 0.48). For definition of thoracic N stages, PET/MR imaging and 18F-FDG PET/CT were concordant in 20 of 22 patients (91%). PET/MR imaging determined the N stage correctly in 20 of 22 patients (91%). 18F-FDG PET/CT determined the N stage correctly in 18 of 22 patients (82%). The mean differences for SUVmean and SUVmax of NSCLC in 18F-FDG PET/MR imaging and 18F-FDG PET/CT were 0.21 and −5.06. These differences were not statistically significant (P &gt; 0.05). The SUVmean and SUVmax measurements derived from 18F-FDG PET/CT and 18F-FDG PET/MR imaging exhibited a high correlation (R = 0.74 and 0.86, respectively; P &lt; 0.0001). Size measurements showed an excellent correlation between 18F-FDG PET/MR imaging and 18F-FDG PET/CT (R = 0.99; P &lt; 0.0001). The lower and upper limits of agreement between 18F-FDG PET/CT and 18F-FDG PET/MR imaging using Bland–Altman analysis were −2.34 to 3.89 for SUVmean, −7.42 to 4.40 for SUVmax, and −0.59 to 0.83 for the tumor size, respectively. Conclusion: 18F-FDG PET/MR imaging using a dedicated pulmonary MR imaging protocol, compared with 18F-FDG PET/CT, does not provide advantages in thoracic staging in NSCLC patients.