Fusion Versus Cognitive MRI Targeted Prostatic Biopsy

Prostate cancer is the second most frequent malignancy (after lung cancer) in men worldwide, counting 1,276,106 new cases and causing 358,989 deaths (3.8% of all deaths caused by cancer in men.

The clinical prostate cancer detection rate of TRUS-guided needle biopsies is only 25-30%. while more than 50% of cancers that require definitive treatment remain undetected during initial biopsies .

Clinical studies have shown that 75-80% of non-palpable carcinomas remain undetected during initial prostate biopsies.

Multi-parametric prostate MRI has a high sensitivity for the detection of prostate adenocarcinoma and has shown promise for targeted biopsy of lesions that may be missed on routine systematic trans -rectal ultrasound (TRUS) biopsy .

The most recent European Association of Urology guidelines recommend MRI before prostate biopsy for biopsy-naïve men with elevated PSA, the strength rating of the recommendation is weak.

A systematic 12-core trans-rectal ultrasound-guided systematic biopsy (TRUS-SB) is still carried out for biopsy-naïve men at present. However, the TRUS-SB technique has several limitations, including over-diagnosis of clinically insignificant prostate cancer (CISCa), under-diagnosis of clinically significant prostate cancer (CSCa), false negative biopsy results and biopsy-related complications, such as bleeding and infections .

Targeted prostate biopsies from MRI-suspicious lesions have been shown to improve the cancer detection rate (CDR) of CSCa compared with systematic TRUS-guided biopsies .

Currently, three biopsy techniques are used for TB from MRI-suspicious lesions: in-bore MRI biopsies, cognitive magnetic resonance imaging trans-rectal ultrasound fusion targeted biopsy (COG-TB) and software guided magnetic resonance imaging-ultrasound fusion targeted biopsies (MRUS-TB). Inbore MRI biopsies that are carried out with an MRI-compatible guidance device can target suspicious lesions accurately; however, such biopsies are time-consuming and expensive .

In the COG-TB technique, a physician samples a location that has been visually estimated using ultrasound and is considered to correspond to the location of a suspicious lesion that was detected on MRI. However, when the suspicious lesion is completely invisible (isoechoic or too small) on TRUS, the accuracy of such biopsies is likely reduced .

The accuracy of COG-TB might be influenced by multiple factors, including the alignment of prostate landmarks, the physician's experience and so on. for these reasons, MRUS-TB where software fuses the MRI images with real-time TRUS images to guide the operator to biopsy the suspicious lesions is more commonly carried out; however, the optimal TB method remains unclear.

Inclusion criteria

• prostate biopsy-naïve men
• PSA levels of up to 20 ng/mL
• Multi-parametric prostate MRI revealed a PIRAD 4 or PIRAD 5.

Exclusion criteria

• PSA level greater than 20 ng/mL
• patient with history of TRUS biopsy
• patient diagnosed as cancer prostate or with distant metastasis