“Prostate cancer and its mimics at multiparametric prostate MRI” by Jinxing Yu et al., published in Br J Radiol

Prostate Cancer and Its Mimics at Multiparametric MRI

Multiparametric MRI (mpMRI) is a pivotal diagnostic tool for prostate cancer, but normal and abnormal conditions often mimic cancer on imaging, complicating diagnosis even for experts.

Typical MRI Features of Prostate Cancer

Cancer Type	Typical MRI Features (mpMRI)
Peripheral zone cancer	Low T2 signal; marked diffusion restriction; rapid contrast wash-in/wash-out; elevated choline peaks
Transitional zone cancer	Homogeneous low T2 signal; ill-defined lenticular mass; rapid contrast; elevated choline peaks
Recurrence post-radiation	Mass-like low T2 signal; diffusion restriction; rapid contrast; high choline, low citrate
Recurrence post-prostatectomy	High T2 signal (compared to muscle); rapid contrast enhancement

Mimics of Prostate Cancer and Their Differentiating Features

Mimic Entity	Key Features for Differentiation
Chronic prostatitis	Mild restriction; no mass effect or contour deformity; symmetric enhancement
Hypertrophic nodule (peripheral/central gland)	Well-defined round margins; symmetric enhancement; normal tissue between nodule and capsule
Post-radiation changes	No strong restriction; no rapid contrast; no increase in choline
Displaced central zone	Base location; symmetric or minimal enhancement; typical location
Pseudolesion (midline peripheral)	Midline, concave contour; no rapid enhancement
Granulomatous prostatitis	Non-enhancing necrotic zones—differentiates from cancer

Quick Summary Table: Cancer vs Mimics

Feature	Cancer	Prostatitis	Hypertrophic Nodule	Radiation Change	Displaced CZ	Pseudolesion
Mass Effect	Yes	No	Sometimes	Rare	No	No
Diffusion Restriction	Marked	Mild	Sometimes	Absent	Yes	Yes
Rapid Contrast	Yes	Mild/Symmetric	Symmetric	Absent	Minimal	Absent
Choline Peak	Elevated	Elevated	Normal/Symmetric	Absent	Variable	Absent

Clinical Application

Careful pattern recognition is essential to distinguish cancer from its mimics on mpMRI, guiding biopsy and management decisions. The PI-RADS scoring system can help structure image interpretation.

Additional Insights and Missing Entities

While the original article provides an excellent foundation on the key mimics of prostate cancer on mpMRI, the following important points and entities are missing or underrepresented:

• Acute Prostatitis: Not discussed, but clinically relevant. Acute prostatitis can present with low T2 signal and mild diffusion restriction. It often has a diffuse or wedge-shaped pattern, and may show increased perfusion and periprostatic edema. It usually does not produce mass effect characteristic of cancer.
• Benign Prostatic Hyperplasia (BPH) Nodules: Beyond hypertrophic nodules, BPH nodules can mimic cancer, especially in the transition zone, with variable MRI features but typically show symmetric enhancement and well-defined margins.
• Post-treatment Scars and Granulation Tissue: Important mimics especially in treated prostates, can cause signal changes that resemble recurrence.
• Technical and Anatomical Pitfalls: Examples include motion artifacts, mispositioned coils, and normal variants such as prominent median lobes or ectopic tissue, which may lead to false positives.

References for Additional Insights

• Prostate imaging features on MRI related to acute prostatitis (PMC9744424)
• Prostatitis - Radiopaedia
• Pitfalls in Interpreting mp-MRI of the Prostate (PMC4656245)
• Diagnosis of recurrent prostate cancer and its mimics at mpMRI (PMC4730977)

Original Article Reference: Jinxing Yu et al., Br J Radiol. Read the full article