MRI and Fusion biopsies K Sahadevan

Consultant Urologist

MRI in Prostate Cancer Diagnosis

Traditionally used for staging purposes 70 to 90% accurate detection of extra capsular disease on

MRI (cornud 2002)

3T MRI, Endorectal coil, MR spectroscpy for improved staging

Currently Diagnostic scan T1,T2, DWI, MRS, DCE Scoring systems Standards of technique

PIRADS

BI-RADS for breast cancer imaging Liberman 2002

ESUR- PIRADS v1, 2012

ESUR-ACR- PIRADS v2, 2015

Hamoen 2015; Metaanalysis Sensitivity 70 to 85 NPV 58 to 95

PIRADS V1 vs V2

Dominant sequence T2W for TZ, DWI for PZ

DCE To downgrade or upgrade PIRADS 3 in PZ

No MRS

New sectoral map

Sectoral map for reporting PIRADS 2

How reliable is MRI?

How reliable is MRI: Heterogeneity Heterogenous studies

Definition of clinically sig disease UCL1: Gleason 4+3 or higher and / or CCL >6mm UCL2: Any Gleason 4 and / or CCL 4mm Epstein criteria +/- ADC <850 mm2/s Gleason score 7 Gleason score 8 PSA >10 ng/ml, PSA density >0.15, clinical stage T2b,

Gleason 4 or 5, total CCL 10 mm Gleason 6–7 with 5% Gleason 4 + either 30% of cores positive

or CCL >8 mm Radiologist experience Variable comparator (extended bx, TR, TP, RRP)

How reliable is MRI?

Futterer 2015 Cancer detection rates of 44% to 87%, NPV 63 to 98%

Ref pts std CSig sens spec PPv NPV

2013 538 fusion G7 94 28 38 91

2015 150 fusion G7, >5% or CCL 8mm

96 50 50 96

2015 115 RRP Epstein 96 46 66 92

PROMIS

Paired cohort, mpMRI follwed by TRUS and template bx

576 pts

TPM detected 40% clinically significant cancers (UCL1)

2% clinically significant cancers missed on MRI

27% may avoid biopsy

UCL1 = Gl 4+3 +/->6mm CCL

Ref sens NPV

MRI 93 89

TRUS 48 74

How reliable is MRI: vs RRP specimen

Delongchamos 2015 14/ 137 (10%) foci of significant cancer (G7/ G6+>0.5ml) missed on mri 4% of tumour missed by targeted biopsy but detected by mrI

Baco 2015 135 pts 5%index lesions (some G6) invisible on MRI 10% index lesions missed on targetted bx

Le 2015 122 pts, 80% index lesion detection 5% targeted bx missed index lesion

Branger 2016: RRP in pts with a negative MRI 17% T3, 14% Primary Gleason 4 or above, 47.5% had secondary Gleason 4 But when MRI expertly re-read, only 4% T3, 4% primary 4

MRI can identify high volume or higher grade tumours in 80-95% of the cases

Evasive lesions!

Targetted biopsies

MR targetted biopsies In bore Not much literature Sensitivities 50 to 80% Expensive, time consuming

Cognitive Less expensive, readily available, do need expertise Variable results but negative sensitivity up to 97% 3D

Software aided

Fusion vs TRUS

Siddiqui 2015: Fusion bx showed 30 higher incidence of high risk 17% lower incidence of low risk cases

Schhots 2015 Metaanalysis approx 2000 pts Higher detection of high risk and lower detection of low risk with

targetted compared to TRUS Sensitivity of MR T bx vs TRUS bx is 91 vs 74%

Wegelin 2016: Systematic TRUS vs Cog Fusion, software fusion, MRI in bore No significant different between modalities, (? In bore >software

fusion>cognitive) Targetted bx higher yield for clinically significant prostate cancer RCT b/w cognitive vs fusion vs in bore on going

Fusion Vs TRUS in RRPSiddiui JAMA

Issues with Fusion

Radiologist Acquisition (angles, pulses, sequences etc) Interpretation (PIRADS)

Urologist Registration/fusion (deformation, position) Identification Needle track/target

Pathologist Inter observer variability

Patient Movement, bowel prep

MRI Fusion: Ideal parameters

Compatibility: In house US probes and with PACS

Suitable for transrectal and trans perineal approaches

Easy workflow and short learning curve

Rigid and elastic registration

Ability to use record needle track

Cost!

MRI/TRUS fusion platforms

Many european and American systems

Usually with own US systems

TR and TP options

Slight variation in physical form

Manual vs robotic arm

Electromagenetic vs visual tracking

Validation studies

Uronav: Philips

Uronav

Support for both transperineal and transrectal biopsy approaches -

Ultrasound-only work flow for guided navigation without the need for pre-biopsy MR data

Display of prior biopsy core locations and data from previous procedures performed with UroNav

Robust, 3D gland segmentation modeling and flexibility to perform dynamic adjustments of the ultrasound segmentation boundary

Elastic (deformable) and rigid registration options -

On-the-fly registration adjustments

Biopsee

Biopsee

Fusion with MRI Spectroscopy, dynamic MRI, PET, PET-CT, SPECT (fusion with any DICOM image type)

3D, elastography, DCE abilities

Automatic 3D ultrasound image acquisition (minimum 1mm slices)

Superb tools for delineating target areas and structures in any image set

Stereotactic biopsy planning module for plotting exact needle paths

Live stereotactic needle navigation with practical guidance tools

Automatic recording of all significant data: exact biopsy coordinates, ultrasound parameters and patient data

Documentation and reporting tool for follow-up

Artemis: Hitachi Aloka

Artemis

Prostate mapping via needle navigation and tracking

Revisit previous sample sites/overlay previous gland volumes

Integrated motion compensation

Automatic recording of all biopsy locations

Automatic 2D to 3D image conversion

BK Fusion BioJet

Triplane Transducer is the only urology transducer that allows you to shift between simultaneous biplane and endfire imaging modes at the touch of a button and without removing the transducer from the patient.

Koelis: available in US

Easote: Virtual navigator

Multiparametric US Sensitivity up to

90%

PPV 50-90%

NPV 60-100%

CEUS

Strain elastography

Shear wave elastography

Summary

MRI is good at detecting high grade, high volume CaP

MRI can influence your biopsy and therapy strategy

TRUS bx or MR guided bx only could miss significant CaP

Experience of the operator plays a major role, standardisation and audit essential

There is a role for fusion biopsy systems and TRUS bx

Biopsy Strategies

MRI can detect high risk CaP but not all

Where do you draw the line for clinically significant CaP?

Do you access to a dedicated uro-radiologist?

Is your finance director friendly?

How much spare theatre capacity do you have?

Any colleagues with interest in taking prostate cancer daignostic pathway further?

Diagnostic pathway strategy

Thank you

Pitfalls MR prostate reporting Panebianco 2015

Diagnostic Bilateral basal hypointense zones (moustache sign) Median posterior hypointense area at the middle third of the gland Transition zone prostate cancer versus BPH foci of stromal hyperplasia Ectopic BPH nodule Granulomatous prostatitis after intravesical instillation of BCG Hypertrophic anterior fibromuscular stroma Periprostatic venous plexus and neurovascular bundle

Staging T3 versus T2 (overlapping with pitfalls in primary diagnosis: granulomatous

prostatitis, periprostatic venous plexus and neurovascular bundle) Bone findings Controversial on lymph nodes

Artifacts Mispositioned endorectal coil Post-biopsy changes Lymphoceles