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A Cognitive Fusion-guided Prostate Biopsy Using Multiparametric Magnetic Resonance Imaging and Transrectal Ultrasound
Published on: March 21, 2025
Natural history of prostatic lesions on serial multiparametric magnetic resonance imaging
Samrad Ghavimi1, Hamidreza Abdi1, Jennifer Waterhouse2
1Department of Urologic Sciences.
Introduction:
The natural history of prostatic lesions identified on multiparametric magnetic resonance imaging (mpMRI) is largely unknown. We aimed to describe changes observed over time on serial MRI.
Methods:
All patients with ≥2 MRI studies between 2008 and 2015 at our institution were identified. MRI progression was defined as an increase in Prostate Imaging Reporting and Data System (PI-RADS; version 2) or size of existing lesions, or the appearance of a new lesion PIRADS ≥4. Patients on active surveillance (AS) were analyzed for correlation of MRI progression to biopsy reclassification.
Results:
A total of 83 patients (54 on AS and 29 for diagnostic purposes) underwent serial MRI, with a mean interval of 1.9 years between scans. At baseline, 115 lesions (66 index, 49 non-index) were identified. Index lesions were more likely than non-index lesions to increase in size ≥2 mm (36.2 vs. 7.3 %; p=0.002). Overall progression was more likely to be seen among the index cohort (34.8 vs. 7.6%; p<0.001). New lesions with PIRADS ≥4 were seen on second imaging in 13 (16.5%) men, and became the index lesion in 29 cases (34.9%). Eighteen men on AS showed evidence of MRI progression (five with new lesions, 13 with progression of a previous lesion). Biopsy reclassification was present in three men (16.7%) with and seven men without MRI progression (19.4%).
Conclusions:
Overall changes in size and PIRADS scores of index lesions on MRI were small. New lesions were common, but usually did not alter management.
Insights
Serial multiparametric MRI (mpMRI) shows that while index prostate lesions rarely change significantly, new lesions are common. These changes typically do not alter management for men on active surveillance.
Area of Science:
- Radiology
- Oncology
- Urology
Background:
- The natural history of prostate lesions detected by multiparametric MRI (mpMRI) is not well understood.
- Serial MRI scans are crucial for monitoring these lesions over time.
Purpose of the Study:
- To describe the changes observed in prostatic lesions on serial mpMRI.
- To evaluate the correlation between MRI progression and biopsy reclassification in patients on active surveillance.
Main Methods:
- Retrospective analysis of 83 patients with at least two MRI studies between 2008 and 2015.
- MRI progression defined by increased PI-RADS score or lesion size, or new PI-RADS ≥4 lesions.
- Analysis of active surveillance patients for MRI progression and biopsy reclassification.
Main Results:
- Index lesions were more likely to increase in size compared to non-index lesions (36.2% vs 7.3%).
- Overall progression was more frequent in the index lesion cohort (34.8%).
- New PI-RADS ≥4 lesions appeared in 16.5% of men, becoming the index lesion in 34.9% of cases.
Conclusions:
- Changes in size and PI-RADS scores of index prostate lesions on MRI were generally small.
- New lesions were frequently observed but typically did not necessitate changes in patient management.
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