Related Experiment Video
Updated: Jun 23, 2025
A Practical Guide for the Production and PET/CT Imaging of 68Ga-DOTATATE for Neuroendocrine Tumors in Daily Clinical Practice
Published on: April 17, 2019
Reasons for Discordance between 68Ga-PSMA-PET and Magnetic Resonance Imaging in Men with Metastatic Prostate Cancer
Jade Wang1, Elisabeth O'Dwyer2, Juana Martinez Zuloaga2
1Department of Internal Medicine, New York-Presbyterian Hospital, New York, NY 10065, USA.
Background:
PSMA PET has emerged as a "gold standard" imaging modality for assessing prostate cancer metastases. However, it is not universally available, and this limits its impact. In contrast, whole-body MRI is much more widely available but misses more lesions. This study aims to improve the interpretation of whole-body MRI by comparing false negative scans retrospectively to PSMA PET.
Methods:
This study was a retrospective sub-analysis of a prospectively collected database of patients who participated in a clinical trial of PSMA PET/MRI comparing PSMA PET and whole-body MRI from 2018-2021. Subjects whose separately read PSMA PET and MRI diagnostic reports showed discrepancies ("false negative" MRI cases) were selected for sub-analysis. The cases were reviewed by the same attending radiologist who originally read the scans. The radiologist noted specific features on MRI indicating metastatic disease that were initially missed.
Results:
Of 263 cases, 38 (14%) met the inclusion criteria and were reviewed. Six classes of mpMRI false negatives were identified: anatomically normal (18, 47%), atypical MRI appearance (6, 16%), mischaracterization (1, 3%), undercall (6, 16%), obscured (4, 11%), and no abnormality on MRI (3, 8%). Considering that the atypical and undercalled cases could have been adjusted in retrospect, and that 4 additional cases had positive lesions to the same extent and 11 further cases had disease confined to the pelvis, only 11 (4%) of the original 263 would have had disease outside of a conventional radiation treatment plan.
Conclusion:
Notably, almost 50% of the cases, including most lymph node metastases, were anatomically normal using standard criteria. This suggests that current anatomic criteria for evaluating prostate cancer lymph node metastases are not ideal, and there is a need for improved criteria. In addition, 32% of cases involved some element of human interpretive error, and, therefore, improving reader training may lead to more accurate results.
Insights
Whole-body MRI misses prostate cancer metastases, but reviewing false negatives against PSMA PET reveals missed lesions. Improving MRI interpretation and reader training can enhance accuracy for detecting cancer spread.
Area of Science:
- Oncology
- Radiology
- Medical Imaging
Background:
- Prostate cancer (PCa) metastases assessment relies on PSMA PET, the gold standard, but its availability is limited.
- Whole-body MRI is more accessible but less sensitive in detecting metastatic lesions compared to PSMA PET.
- This study addresses the underutilization of whole-body MRI by analyzing discrepancies with PSMA PET to improve its diagnostic performance.
Purpose of the Study:
- To enhance the interpretation of whole-body MRI for prostate cancer metastases by retrospectively comparing false-negative MRI scans with PSMA PET findings.
- To identify specific MRI features that were initially overlooked in cases of missed metastatic disease.
Main Methods:
- Retrospective sub-analysis of a prospectively collected database of patients from a PSMA PET/MRI clinical trial (2018-2021).
- Inclusion criteria: patients with discrepancies between PSMA PET and whole-body MRI reports, identified as "false negative" MRI cases.
- Review of selected cases by the original attending radiologist to identify initially missed MRI findings indicative of metastatic disease.
Main Results:
- 38 (14%) of 263 cases met inclusion criteria for review.
- Six classes of MRI false negatives were identified: anatomically normal (47%), atypical appearance (16%), mischaracterization (3%), undercall (16%), obscured (11%), and no abnormality (8%).
- Nearly 50% of false negatives were anatomically normal on MRI, and 32% involved interpretive errors, suggesting limitations in current criteria and training.
Conclusions:
- Current anatomic criteria for evaluating prostate cancer lymph node metastases on MRI are suboptimal, necessitating improved diagnostic standards.
- Enhancing reader training in interpreting whole-body MRI can significantly reduce interpretive errors and improve detection rates.
- Despite limitations, optimizing MRI interpretation could reduce the number of cases with disease outside conventional treatment plans.
More Related Videos
06:08A Cognitive Fusion-guided Prostate Biopsy Using Multiparametric Magnetic Resonance Imaging and Transrectal Ultrasound
Published on: March 21, 2025
10:28Gene Regulation and Targeted Therapy in Gastric Cancer Peritoneal Metastasis: Radiological Findings from Dual Energy CT and PET/CT
Published on: January 22, 2018
Related Concept Videos
01:29Positron Emission Tomography
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body...
01:25Imaging Studies II: Positron Emission Tomography and Scintigraphy
Fundamental Principles of PET