Does T1- and diffusion-weighted magnetic resonance imaging give value-added than bone scintigraphy in the follow-up of vertebral metastasis of prostate cancer?

Advancing Prostate Cancer Staging: A Single-Step Approach With Bi-parametric and Whole-Body Diffusion MRI in an African Cohort

OBJECTIVES

 To document our initial experience using whole-body diffusion-weighted magnetic resonance imaging (WB-DWI/MRI) and bi-parametric magnetic resonance imaging (bpMRI) as a single exam in the staging of biopsy-proven prostate cancers.

METHODS

This retrospective study involved 120 African men with biopsy-confirmed prostate cancer (PCa). All the participants had a single exam that included both a bpMRI and a WB-DWI/MRI. The results were analyzed based on the American Urological Association's risk stratification system and evaluated using descriptive statistics.

RESULTS

The combined imaging approach confirmed PCa in all cases, identifying pelvic lymph node metastases in 21 (17.5%) patients. Among 72 high-risk patients, bpMRI+WB-DWI/MRI detected pelvic lymph node metastases in 18 (25.0%), bone metastases in 15 (20.8%), retroperitoneal lymph node metastases in six (8.3%), and extraprostatic extension in 18 (25%), with no solid organ metastases observed.

CONCLUSION

The combination of WB-DWI/MRI and bpMRI in a single-step approach demonstrates diagnostic potential in primary prostate cancer staging for high-risk groups, with the added advantage of shorter examination times, lower patients' costs, and elimination of the risks of adverse events associated with the use of contrast agents and exposure to radiation.

Differential diagnosis between metastatic and osteoporotic vertebral fractures using sagittal T1-weighted magnetic resonance imaging

BACKGROUND

Magnetic resonance imaging (MRI) is the most helpful for determining the differential diagnosis between metastatic and osteoporotic vertebral fractures; especially whole spine MRI is effective if patients have multiple spinal metastases. However, it is time-consuming to obtain all planes for all metastatic vertebrae. If we can differentiate these metastatic and osteoporotic vertebral fractures based on only one section and signal intensity, it would save time and be effective for patients with pain. This study investigated the usefulness of sagittal T1-weighted MRI findings in differentiating metastatic and osteoporotic vertebral fractures.

METHODS

We retrospectively reviewed patients diagnosed with metastatic or osteoporotic vertebral fractures. Findings characteristic of metastatic fractures were considered: (a) pedicle or posterior element involvement; (b) convex posterior border of the vertebral body; (c) epidural infiltration; and (d) diffuse homogeneous low signal intensity; findings characteristic of osteoporotic compression fractures were also considered: (e) low-signal-intensity band and (f) posterior retropulsion. Chi-square test or Fisher's exact probability test was used to investigate the usefulness of each MRI finding. Intra- and inter-observer reliability analysis was performed.

RESULTS

This study comprised 43 patients with metastases (45 vertebrae) and 118 patients with osteoporotic fractures (156 vertebrae). All findings showed significant difference with each fracture (p-value: <0.01 to 0.03). Although each MRI finding exhibited high intra- and inter-observer reliability (κ: 0.66 to 1.00), finding (c) exhibited low reliability. Finding (a) showed high sensitivity (88.9%) and usefulness for screening, and findings (b), (d), (e), and (f) showed high specificity (90.4%-100%) and usefulness for definitive diagnosis.

CONCLUSIONS

Characteristic findings with sagittal T1-weighted MRI were useful in the differential diagnosis of metastatic and osteoporotic vertebral fractures. To prevent overlooking metastatic fractures with sagittal T1-weighted MRI, findings of the pedicle or posterior element involvement should be focused on because of its reliability and sensitivity.

Spinal metastasis: diagnosis, management and follow-up

Spine metastatic disease is an increasingly common occurrence in cancer patients due to improved patient survival. Close proximity of the bony spinal column to the spinal cord limits many conventional treatments for metastatic disease. In the past decade, we have witnessed dramatic advancements in therapies, with improvements in surgical techniques and recent adoption of spine stereotactic radiotherapy techniques leading to improved patient outcomes. Multidisciplinary approaches to patient evaluation, treatment and follow-up are essential. Imaging plays an ever increasing role in disease detection, pre-treatment planning and assessment of patient outcomes. It is important for the radiologist to be familiar with imaging algorithms, best practices for surgery and/or radiotherapy and imaging findings in the post-treatment period that may indicate disease recurrence. In this review, we present a multidisciplinary discussion of spine metastases, with specific focus on pre-treatment imaging, planning, current treatment approaches, and post-treatment assessment.