Diagnostic Value of Diffusion-Weighted Imaging in Simultaneous 18F-FDG PET/MR Imaging for Whole-Body Staging of Women with Pelvic Malignancies

Journal of Nuclear Medicine

Martin Heubner¹  Sonja Kinner¹  Verena Ruhlmann¹  Johannes Grueneisen¹  Thomas Lauenstein¹  Karsten Beiderwellen¹  Lale Umutlu¹  Michael Forsting¹  Antonia Schulze-Hagen¹  Benedikt Michael Schaarschmidt¹ 

关键词: PET/MRI;    diffusion-weighted imaging;    ¹⁸F-FDG PET;    gynecological cancers;   

DOI  :  10.2967/jnumed.114.146886

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

The aim of this study was to assess the diagnostic benefit of diffusion-weighted imaging (DWI) in an 18F-FDG PET/MR imaging protocol for whole-body staging of women with primary or recurrent malignancies of the pelvis. Methods: Forty-eight patients with a primary pelvic malignancy or suspected recurrence of a pelvic malignancy were included in our study. All patients underwent a whole-body 18F-FDG PET/MR imaging examination that included DWI. Two radiologists separately evaluated the PET/MR imaging datasets without DWI followed by a second interpretation with DWI. First, both readers identified all primary tumors, as well as lymph node and distant metastases. In a second session, PET and DWI data were assessed qualitatively. Image interpretation comprised lesion conspicuity defined as visual lesion-to-background contrast (4-point ordinal scale) and diagnostic confidence (3-point ordinal scale) for all tumors. The results from histopathologic examination and cross-sectional imaging follow-up (≥6 mo) were used as the reference standard. Statistical analysis was performed to assess the significance of differences between obtained values. Results: Among the 122 suspected lesions seen, 98 (80.3%) were considered malignant. PET/MR imaging without DWI had a sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of 92.9%, 87.5%, 96.8%, 75.0%, and 91.8%, respectively, for the detection of malignant lesions. PET/MR imaging with DWI had slightly higher values (94.9%, 83.3%, 95.9%, 80.0%, and 92.6%, respectively), but the difference was not significant (P > 0.05). In the qualitative assessment of lesion-to-background contrast, PET had significantly (P < 0.05) higher values (3.79 ± 0.58) than DWI (3.63 ± 0.77). Furthermore, significantly (P < 0.05) higher scores were found for diagnostic confidence using PET (2.68 ± 0.64) for the determination of malignant lesions, when compared with DWI (2.53 ± 0.69). Conclusion: DWI in PET/MR imaging has no diagnostic benefit for whole-body staging of women with pelvic malignancies. The omission of DWI for staging or restaging gynecologic cancer may significantly reduce examination times, thus increasing patient comfort without a relevant decrease in diagnostic competence.

【 授权许可】

Unknown