Monoparametric high-resolution diffusion weighted MRI as a possible first step in an MRI-directed diagnostic pathway for men with suspicion of prostate cancer

Jeroen Sebastiaan Reijnen; Una Ryg; Jon B Marthinsen; Irina Schönhardt; Therese Seierstad; Knut H Hole

doi:10.3389/fonc.2023.1102860

Monoparametric high-resolution diffusion weighted MRI as a possible first step in an MRI-directed diagnostic pathway for men with suspicion of prostate cancer

Front Oncol. 2023 Jan 31:13:1102860. doi: 10.3389/fonc.2023.1102860. eCollection 2023.

Authors

Jeroen Sebastiaan Reijnen^{1

2}, Una Ryg^{2

3}, Jon B Marthinsen¹, Irina Schönhardt⁴, Therese Seierstad³, Knut H Hole^{2

3}

Affiliations

¹ Department of Radiology, Sørlandet Hospital Trust, Kristiansand, Norway.
² Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
³ Division of Radiology and Nuclear Medicine, Radiumhospitalet, Oslo University Hospital, Oslo, Norway.
⁴ Department of Pathology, Sørlandet Hospital Trust, Kristiansand, Norway.

Abstract

Purpose: To explore if a high-resolution diffusion weighted MRI sequence (DWI-only) could be used as a first step in an MRI-directed diagnostic pathway.

Methods: Prospective single center study that between December 2017 and August 2018 included 129 consecutive patients with suspicion of prostate cancer into a PI-RADS-based MRI-directed diagnostic pathway. All patients had multiparametric MRI (mpMRI). Based on only the transversal high-resolution DWI images two consultant radiologists prospectively categorized the findings as positive, equivocal, or negative for clinically significant cancer. The radiologists then interpreted the mpMRI and assigned a PI-RADS score. A third independent reader retrospectively categorized the DWI-only exams without access to the mpMRI. The interpretations of DWI-only were compared to the PI-RADS classification from mpMRI and the histopathology from the biopsies. Non-biopsied patients were followed in a safety net monitoring for 56 months.

Results: Based on DWI-only, 29 (22.5%) of the exams were categorized as negative, 38 (29.5%) as equivocal and 62 (48.1%) as positive. Of the 56 patients with PI-RADS 4-5 at mpMRI, 55 were also categorized as positive at DWI-only. All patients diagnosed with clinically significant cancer were identified using DWI-only. 56 months of safety net monitoring did not reveal any clinically significant cancers among patients with exams categorized as negative or equivocal. There was high inter-reader agreement on positive findings, but less agreement on negative and equivocal findings.

Conclusions: In this concept study, the monoparametric DWI-only identified all patients with clinically significant cancer in a mpMRI-directed diagnostic pathway.

Keywords: algorithms (MeSH term); follow-up studies; magnetic resonance imaging; prospective studies; prostatic neoplasms.