Diagnostic performance of whole-body [18F]FDG PET/MR in cancer M staging: A systematic review and meta-analysis

Abstract

Objectives: To calculate the pooled diagnostic performances of whole-body [¹⁸F]FDG PET/MR in M staging of [¹⁸F]FDG-avid cancer entities.

Methods: A diagnostic meta-analysis was conducted on the [¹⁸F]FDG PET/MR in M staging, including studies: (1) evaluated [¹⁸F]FDG PET/MR in detecting distant metastasis; (2) compared[ ¹⁸F]FDG PET/MR with histopathology, follow-up, or asynchronous multimodality imaging as the reference standard; (3) provided data for the whole-body evaluation; (4) provided adequate data to calculate the meta-analytic performances. Pooled performances were calculated with their confidence interval. In addition, forest plots, SROC curves, and likelihood ratio scatterplots were drawn. All analyses were performed using STATA 16.

Results: From 52 eligible studies, 2289 patients and 2072 metastases were entered in the meta-analysis. The whole-body pooled sensitivities were 0.95 (95%CI: 0.91-0.97) and 0.97 (95%CI: 0.91-0.99) at the patient and lesion levels, respectively. The pooled specificities were 0.99 (95%CI: 0.97-1.00) and 0.97 (95%CI: 0.90-0.99), respectively. Additionally, subgroup analyses were performed. The calculated pooled sensitivities for lung, gastrointestinal, breast, and gynecological cancers were 0.90, 0.93, 1.00, and 0.97, respectively. The pooled specificities were 1.00, 0.98, 0.97, and 1.00, respectively. Furthermore, the pooled sensitivities for non-small cell lung, colorectal, and cervical cancers were 0.92, 0.96, and 0.86, respectively. The pooled specificities were 1.00, 0.95, and 1.00, respectively.

Conclusion: [¹⁸F]FDG PET/MR was a highly accurate modality in M staging in the reported [¹⁸F]FDG-avid malignancies. The results showed high sensitivity and specificity in each reviewed malignancy type. Thus, our findings may help clinicians and patients to be confident about the performance of [¹⁸F]FDG PET/MR in the clinic.

Clinical relevance statement: Although [¹⁸F]FDG PET/MR is not a routine imaging technique in current guidelines, mostly due to its availability and logistic issues, our findings might add to the limited evidence regarding its performance, showing a sensitivity of 0.95 and specificity of 0.97.

Key points: • The whole-body [¹⁸F]FDG PET/MR showed high accuracy in detecting distant metastases at both patient and lesion levels. • The pooled sensitivities were 95% and 97% and pooled specificities were 99% and 97% at patient and lesion levels, respectively. • The results suggested that ¹⁸F-FDG PET/MR was a strong modality in the exclusion and confirmation of distant metastases.

Keywords: Fluorodeoxyglucose F18; Magnetic resonance imaging; Neoplasms; Positron emission tomography.