Multiparametric Whole-body MRI with Diffusion-weighted Imaging and ADC Mapping for the Identification of Visceral and Osseous Metastases From Solid Tumors

Abstract

Rationale and objectives: The purpose of this study was to investigate the use of multiparametric, whole-body, diffusion-weighted imaging (WB-DWI) and apparent diffusion coefficient (ADC) maps with T2-weighted magnetic resonance imaging (MRI) at 3T for the detection and monitoring of metastatic disease in patients.

Materials and methods: Fifty-four participants (32 healthy subjects and 22 patients) were scanned with WB-DWI methods using a 3T MRI scanner. Axial, sagittal, or coronal fat-suppressed T2-weighted (T2WI), T1-weighted (T1WI), and DWI images were acquired. Total MRI acquisition and set-up time was approximately 45 minutes. Metastatic disease on MRI was confirmed based on T2WI characteristics. The number of lesions was established on computed tomography (CT) or positron emission tomography (PET-CT). Whole-body ADC maps and T2WI were constructed, and region-of-interests were drawn in normal and abnormal-appearing tissue for quantitative analysis. Statistical analysis was performed using a paired t tests and P < .05 was considered statistically significant.

Results: There were 91 metastatic lesions detected from the CT or PET-CT with a missed recurrent lesion in the prostate. Multiparametric WB-MRI had excellent sensitivity (96%) for detection of metastatic lesions compared to CT. ADC map values and the ADC ratio in metastatic bone lesions were significantly increased (P < .05) compared to normal bone. In soft tissue, ADC map values and ratios in metastatic lesions were decreased compared to normal soft tissue.

Conclusion: We have demonstrated that multiparametric WB-MRI is feasible for oncologic staging to identify bony and visceral metastasis in breast, prostate, pancreatic, and colorectal cancers. WB-MRI can be tailored to fit the patient, such that an "individualized patient sequence" can be developed for a comprehensive evaluation for staging and response during treatment.

Keywords: Metastatic disease; breast; cancer; colon; diffusion-weighted imaging; magnetic resonance imaging; prostate; whole-body magnetic resonance imaging.

Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Demonstration of multiparametric whole-body MRI in a normal subject. A. T2-weighted imaging through the central slices in the body. B. T1-weighted images and C. ADC maps of the same location in the normal subject.

Figure 2

Demonstration of WB-MRI on a 66-year-old man with metastatic prostate cancer. A. Axial diffusion imaging through the thorax and pelvis shows multiple metastatic lesions in the ribs, sternum, and vertebrae. B. 3D visualization of the thorax showing the metastatic lesions in the chest. C. T2 and STIR imaging of the spine to correlate the metastatic lesions with the WB-MRI.

Figure 3

Demonstration of the of the WB-DWI in a 46-year-old- woman with metastatic breast cancer. A.) Three-dimensional visualization of metastatic lesions using different b values from the DWI. There are progressive changes in the DWI signal intensity within the metastatic sites (white arrows) of the left pelvis, thoracic and lumbar spine, and liver. B.) A coronal ADC map through the midsection of the patient. C.) Different b-values from WB-DWI sagittal images of the spine showing multiple metastatic regions.

Figure 4

Demonstration of the WB-MRI and PET/CT in a 46-year-old woman with metastatic breast cancer in the liver and pelvis. A.) The white arrows in liver and pelvis show metastatic lesions on PET and T2-weighted images. B.) The PET and ADC maps demonstrate the metastatic lesions (white arrows) in the liver. In the pelvis, the yellow arrows indicate normal bone on the ADC map and PET. The white arrows show the metastatic lesions. C.) The same metastatic sites are noted on the WB-MRI diffusion-weighted images (b=800) and the ADC map.

Figure 5

Example of WB-MRI screening in 60-year-old man with a stage T2B, Gleason 9 with increasing PSA, post external beam radiation and androgen deprivation therapy. A. CT and whole-body MRI was performed for interrogation of metastatic disease. Potential recurrence was only found in the right peripheral zone on the WB-ADC map and shown in the yellow box. B. Localized MRI with DWI/ADC and Pharmacokinetic-DCE (PK-DCE) was performed “on the fly” for confirmation of prostate cancer recurrence.