AUTHOR=Guo Rui , Xu Pengpeng , Cheng Shu , Lin Mu , Zhong Huijuan , Li Weixia , Huang Hengye , Ouyang Bingsheng , Yi Hongmei , Chen Jiayi , Lin Xiaozhu , Shi Kuangyu , Zhao Weili , Li Biao 

TITLE=Comparison of Nasopharyngeal MR, 18 F-FDG PET/CT, and 18 F-FDG PET/MR for Local Detection of Natural Killer/T-Cell Lymphoma, Nasal Type

JOURNAL=Frontiers in Oncology

VOLUME=10

YEAR=2020

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2020.576409

DOI=10.3389/fonc.2020.576409

ISSN=2234-943X

ABSTRACT=<sec><title>Objectives</title><p>The present study aims to compare the diagnostic efficacy of MR, <sup>18</sup>F-FDG PET/CT, and <sup>18</sup>F-FDG PET/MR for the local detection of early-stage extranodal natural killer/T-cell lymphoma, nasal type (ENKTL).</p></sec><sec><title>Patients and Methods</title><p>Thirty-six patients with histologically proven early-stage ENKTL were enrolled from a phase 2 study (Cohort A). Eight nasopharyngeal anatomical regions from each patient were imaged using <sup>18</sup>F-FDG PET/CT and MR. A further nine patients were prospectively enrolled from a multicenter, phase 3 study; these patients underwent <sup>18</sup>F-FDG PET/CT and PET/MR after a single <sup>18</sup>F-FDG injection (Cohort B). Region-based sensitivity and specificity were calculated. The standardized uptake values (SUV) obtained from PET/CT and PET/MR were compared, and the relationship between the SUV and apparent diffusion coefficients (ADC) of PET/MR were analyzed.</p></sec><sec><title>Results</title><p>In Cohort A, of the 288 anatomic regions, 86 demonstrated lymphoma involvement. All lesions were detected by <sup>18</sup>F-FDG PET/CT, while only 70 were detected by MR. <sup>18</sup>F-FDG PET/CT exhibited a higher sensitivity than MR (100% vs. 81.4%, χ<sup>2</sup> = 17.641, <italic>P</italic> &lt; 0.001) for local detection of malignancies. The specificity of <sup>18</sup>F-FDG PET/CT and MR were 98.5 and 97.5%, respectively (χ<sup>2</sup> = 0.510, <italic>P</italic> = 0.475). The accuracy of <sup>18</sup>F-FDG PET/CT was 99.0% and the accuracy of MR was 92.7% (χ<sup>2</sup> = 14.087, <italic>P</italic> &lt; 0.001). In Cohort B, 72 anatomical regions were analyzed. PET/CT and PET/MR have a sensitivity of 100% and a specificity of 92.5%. The two methods were consistent (κ = 0.833, <italic>P</italic> &lt; 0.001). There was a significant correlation between PET/MR SUVmax and PET/CT SUVmax (<italic>r</italic> = 0.711, <italic>P</italic> &lt; 0.001), and SUVmean (<italic>r</italic> = 0.685, <italic>P</italic> &lt; 0.001). No correlation was observed between the SUV and the ADC.</p></sec><sec><title>Conclusion</title><p>In early-stage ENKTL, nasopharyngeal MR showed a lower sensitivity and a similar specificity when compared with <sup>18</sup>F-FDG PET/CT. PET/MR showed similar performance compared with PET/CT.</p></sec>