A Study to Evaluate the Performance of Confocal Microscopy to Detect Positive Margins During Radical Prostatectomy

Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexMale
Age18+
SponsorUniversity College, London

About this trial

The goal of this study is to find out whether a new method called "LaserSAFE" can accurately detect cancer at the edge of the prostate (called a positive margin) during prostate surgery. LaserSAFE uses a special microscope in the operating room to quickly scan the prostate after it has been removed from the body. This information can help surgeons decide whether it is safe to preserve the nerves around the prostate. This is especially important for patients who are not usually considered suitable for nerve-sparing surgery using current methods. The study will also assess how quickly and reliably LaserSAFE provides this information during surgery.

The main questions it aims to answer are:

Can LaserSAFE accurately detect cancer at the edges of the prostate during surgery? Can LaserSAFE help surgeons safely decide whether to preserve or remove the surrounding nerves?

Researchers will evaluate the use of the LaserSAFE technique during surgery to see if it improves decision-making about nerve preservation compared to standard practice.

Participants will:

Complete a quality of life questionnaire before surgery Undergo standard prostate surgery, where the surgeon will initially try to preserve the nerves Have their removed prostate analysed during surgery using the LaserSAFE technique Have additional tissue removed if LaserSAFE detects cancer at the edges of the prostate Attend routine follow-up visits as part of standard care Complete quality of life questionnaires at 3 and 12 months after surgery

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Patients diagnosed with clinically significant operable cT2-T3a N0 M0 PC.

Medically fit to undergo RARP.

Scheduled for robot-assisted RARP with a recommendation against intrafascial nerve sparing on at least 1 side based on multidisciplinary meetings informed by MRI, biopsy result and clinical factors.

Ability to read English sufficiently to understand PIS and able to give informed consent.

Disqualifiers

Patients who received neo-adjuvant ADT.

MRI informed very low likelihood for extra prostatic extension in the proximity of NVB (Based on EPE Likert 1 score or tumour away from the posterolateral areas of the prostate)

MRI informed high likelihood for extra prostatic extension in the proximity of NVB (based on Likert 5 score or bulging tumour on MRI T2 images)

Patients in whom preoperative imaging shows rectal involvement or seminal vesicle invasion in which nerve-sparing is deemed not feasible due to oncological safety concerns.

Trial design

Design model

Single group

Treatments tested in this trial

  • LaserSAFE

    Diagnostic test

    The LaserSAFE intervention uses the Histolog® fluorescence confocal microscope to provide real-time tissue visualization at near-cellular resolution. The CE/UKCA/FDA-approved system uses non-ionizing 488nm laser light to capture high-resolution images of areas up to 48×36mm in approximately 60 seconds. Specimen preparation involves cleaning the excised prostate, staining with Histolog Dip® solution for 10 seconds, rinsing with saline, and positioning on the scanner. Both posterolateral surfaces are imaged sequentially, with total acquisition under 5 minutes before standard formalin processing. Image interpretation by trained pathologists identifies positive surgical margins (PSMs), documenting margin dimensions and multifocality. Findings are communicated intraoperatively to guide nerve preservation decisions. Secondary resection of the ipsilateral neurovascular bundle is performed when posterolateral PSMs exceed 3mm (single margin) or multiple PSMs are detected.

Treatment groups

No treatment groups listed

Trial outcomes

Primary outcomes

1

Sensitivity

Sensitivity of LaserSAFE to detect positive margins in the posterolateral area of the prostate of more than 3 mm compared against final paraffin analysis Sensitivity will be monitored across the trial when the first 150, 300 and 500 participants have been recruited. If sensitivity decreases below 85%, trial methodology will be reviewed and if considered appropriate the trial will be stopped.

Time frame
12 months

Secondary outcomes

1

Accuracy metrics for any size of positive margin

Overall sensitivity, specificity, PPV and NPV of LaserSAFE compared to FFPE analysis for any length of PSM

Time frame
12 months
2

Determination of Margin Length Cut-off for Secondary Resection

The study will evaluate the optimal cut-off for positive margin length that should trigger a secondary resection, with the aim of maximising nerve-sparing without compromising oncological safety

Time frame
12 months
3

Accuracy metrics for positive margins more than 3 mm

Overall specificity, PPV and NPV of LaserSAFE compared to FFPE analysis for any PSM \> 3 mm.

Time frame
12 months
4

Residual prostate cancer rate

Rate of residual prostate cancer in secondary resections of the neurovascular bundle

Time frame
12 months

Other outcomes

Sponsors and contacts

Click on the lead sponsor to view all of their trials.