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Evaluating the Effects of Frozen Section Technology on Oncological and Functional Outcomes at Radical Prostatectomy.

A Single Blinded, IDEAL Stage 3, Multi-Centre, Randomised Controlled Trial to Assess NeuroSAFE Robotic Assisted Radical Prostatectomy (RARP) vs Standard Robotic Assisted Radical Prostatectomy (RARP) in Men With Prostate Cancer

Status
Active, not recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03317990
Acronym
NeuroSAFEPROOF
Enrollment
407
Registered
2017-10-23
Start date
2018-04-09
Completion date
2027-12-31
Last updated
2025-09-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prostate Cancer

Keywords

Prostate Cancer, Nerve sparing, NeuroSAFE, Frozen section

Brief summary

In summary this trial will test whether this new surgical technique can be used to make surgery safer and more effective whilst allowing improved quality of life for patients having surgery for prostate cancer. If the technique is proven effective the investigators will use the experience gained to promote its use throughout the NHS through training courses and publication and dissemination of the resultant data. Staff from centres participating in this trial will be fully trained in the NeuroSAFE technique. A patient and public involvement afternoon was held for participants of the NeuroSAFE PROOF feasibility study, family members, men with prostate cancer, and staff members at UCLH. The event was supported by the charity Orchid Cancer appeal. The high levels of attendance was demonstrative of the support within our patient group for the work of this trial. The trial team listened to the comments made by participants and members of the public and have made some changes to the design of our trial as a result of this feedback.

Detailed description

Prostate cancer is very common and results in the death of many men in the developed world. Prostate cancer that has not spread outside the prostate can usually be cured by surgical removal of the prostate gland (radical prostatectomy). Radical Prostatectomy can be associated with urinary incontinence due to damage to the involuntary sphincter and erectile dysfunction due to damage of the nerves that run within the outer coverings of the prostate. Surgical sparing of these nerves to preserve quality of life may risk leaving cancer cells behind often meaning that the patients need extra treatment with radiotherapy. This trial is designed to evaluate a new method designed to decrease the risk of compromising cancer control associated with sparing of the nerves as well as evaluate effects on the need for radiotherapy after surgery if cancer is left behind. The Investigators will also evaluate effects on the quality of life in patients who have undergone RARP. The trial is needed now because the nature of prostate cancers treated surgically is changing rapidly. The techniques developed in low risk cancer to spare the nerves which run alongside the prostate, may not necessarily be safe when used on the more aggressive cancers operated on nowadays and if they are adopted without adequate investigation, the risk is that patients will be exposed to increased risk of cancer recurrence and needing extra treatment with radiotherapy with consequent side effects and extra cost to the NHS. On the outside of the prostate, within its outermost coverings, run the nerves thought to be responsible for producing erections. Preservation of these nerves has also been linked to more rapid reestablishment of urinary continence following surgical removal of the prostate. Robotic technology has been developed which allows the prostate to be removed through very small incisions. The surgeons view is magnified in 3D, which facilitates the peeling off of the outer layers, containing the nerves (so called nerve sparing). With nerve sparing the nerves controlling erections are left intact whilst the prostate itself, along with the cancer within it, is removed. This increases the patient's chances of getting erections of sufficient quality for penetrative sex. Data from several case series, including our own, suggest that the higher the degree of nerve sparing performed, the more likely a patient is to be potent and continent of urine. In our series, bilateral nerve sparing results in 85% of men being able to get usable erections\*, whereas only 45% of men will have useable erections\* when only one side is spared. Nerve sparing has largely been developed and the effects have been evaluated in the USA where prostate cancer is detected at an earlier stage because PSA screening is performed commonly. In the UK, where PSA screening is not commonly carried out, tumours resected at surgery are larger and more aggressive, often having spread through the capsule of the prostate. In addition, the move away from surgery for small low-grade tumours in the UK means that the prostate cancers treated by surgery are larger and more aggressive overall. This means that the tumours are closer to the outer limit of the prostate because the more aggressive tumours tend to work their way out through the outer capsule of the prostate. A nerve sparing approach is associated with an increased risk that tumour will be left on the surface of the resected specimen. This is referred to as a positive surgical margin (PSM). One of the principles of (radical) cancer surgery is that cancerous tissue should be removed with a covering of non-cancerous tissue to give the best chance of cure (a so called negative or clear surgical margin). Positive surgical margins are associated with an increased chance of recurrence following surgery and require further treatment, usually with radiotherapy, which is expensive and engenders its own side effects. The investigators plan to evaluate the use of a modified version of a frozen section technique called NeuroSAFE in promoting nerve sparing without diminishing the oncological effects of surgery by generating PSMs. During this frozen section technique, once the prostate is removed, the areas of prostate adjacent to the spared nerves are sliced from the surgical specimen and rapidly frozen and stained so that they can be examined carefully by a pathologist. If the pathologist identifies a significant positive surgical margin, the spared nervous tissue on that side will be surgically resected before the patient is woken up at the end of the operation. When this is done the cancer behaves as if it had been resected with a negative surgical margin at the outset. Frozen section analysis does not add much time to the surgical procedure, as once the prostate is removed, the rest of the operation (joining the bladder to the urethra and removing pelvic lymph nodes) can proceed whilst the frozen section analysis is performed. Patients enrolled to the trial will be randomised between A) standard UK nerve sparing practice, wherein the degree to which the nerves can be spared is determined by the operating surgeon based on clinical examination, biopsy results and multi-parametric MRI and B) bilateral nerve sparing with frozen section analysis. The Trial team recently surveyed UK robotic prostatectomists and confirm that currently UK surgeons predominately rely on MRI, biopsy and Digital Rectal Exam (DRE) findings to determine whether they can spare nerves, but that there is little consistency in the means by which a surgeon decides whether or not they can spare nerves in a particular case. Our survey tells us that UK surgeons do not use frozen section to direct nerve sparing with only 5% of UK prostatectomists ever having used it at all. What are the potential outcomes of this research? This trial will provide a thorough evaluation of a new technique designed to minimise the occurrence of PSM and exposure to extra treatment or cancer recurrence. It will generate vital data regarding the cost/benefit of using this procedure. The relationship between the degree and frequency of nerve sparing on quality of life will be evaluated in terms of sexual potency and urinary continence in UK patients undergoing RALP. The assessment of these functions will include patient reported outcomes. \* At 2 years following surgery using Viagra or an equivalent PDE5i.

Interventions

When the prostate is removed from within the patient as it is disconnected from its attachments. The specimen will then be painted (right=blue, left =black) by the operating surgeon and delivered expediently to the pathologist who will perform frozen section analysis of the painted areas. The pathologist will remove the pre-painted surface of the gland (which had been in contact with the neurovascular bundles) using a sharp blade. The tissue sample will be snap frozen and embedded in OCT. If a significant positive margin (on more than one section from one side or in a single section but greater than or equal to 3mm) is reported by the pathologist, the entire neurovascular bundle on the affected side will be removed and sent for formal pathological examination.

PROCEDUREStandard RARP

Patients will undergo the standard intervention - RARP without NeuroSAFE Frozen section analysis

Sponsors

North Bristol NHS Trust
CollaboratorOTHER
Sheffield Teaching Hospitals NHS Foundation Trust
CollaboratorOTHER
University College London Hospitals
CollaboratorOTHER
NHS Greater Glasgow and Clyde
CollaboratorOTHER
University College, London
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)

Masking description

Patients will be blinded as to whether the person has had NeuroSAFE procedure. The surgeon and pathologist cannot be blinded to this.

Intervention model description

A single blinded, multi-centre, randomised controlled trial. Parallel group, two-arm, with 1:1 allocation ratio between nerve sparing guided by NeuroSAFE and current UK practice (guided by MRI, biopsy and clinical examination).

Eligibility

Sex/Gender
MALE
Age
18 Years to 75 Years
Healthy volunteers
No

Inclusion criteria

1. Men opting to undergo RARP for organ confined prostate cancer. 2. Potent men (IIEF 22-25 not using PDE5i or other medications or vacuum pump) 3. Men who are continent of urine (no self-reported urinary incontinence) 4. Has given written informed consent 5. Ability to read English sufficiently to answer questionnaires and understand PIS

Exclusion criteria

1. Unable to undergo robotic prostatectomy 2. Known urinary incontinence 3. Previous treatment for prostate cancer 4. Previous/current hormone treatment for prostate cancer 5. Nerve sparing deemed futile due to locally advanced disease by surgeon and radiologist

Design outcomes

Primary

MeasureTime frameDescription
Erectile Function1 yearComparison of the erectile function at 12-months according to allocated treatment arm (i.e. NeuroSAFE RARP \[intervention\] vs. standard RARP \[control\]). Erectile function is measured using the IIEF-5 questionnaire Measure Description: The International Index of Erectile Function-5 (IIEF-5) measures erectile dysfunction severity. Total scores range from 5 to 25, calculated by summing 5 items. Higher scores indicate better erectile function. Severity categories: 22-25 = no erectile disfunction, 17-21 = mild, 12-16 = mild to moderate, 8-11 = moderate, 5-7 = severe. No subscales are used; the total score is the sum of all items.

Secondary

MeasureTime frameDescription
Functional Outcome - Urinary Continence at 6 Months6 monthsComparison of the continence at 3 months, measured using the ICIQ questionnaire between intervention and control arms. o Additional subgroup analysis: restricted to men who did not receive a pre-operative radiologist recommendation for bilateral nerve sparing The International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) assesses the frequency, severity, and impact of urinary incontinence. Total scores range from 0 to 21, with higher scores indicating more severe symptoms. Scores are calculated by summing 3 scored items. No subscales are used; higher values represent worse outcomes.
Oncological Outcome12 months after surgeryOncological outcome will be classified into four categories according to the following definition: 1. PSA persistence : PSA≥0.2 at visit 2 2. Biochemical recurrence: (PSA less than 0.2 at visit 2) and (PSA≥0.2 at visit 3 or PSA≥0.2 at visit 4) 3. Early salvage treatment: (PSA less than 0.2 at each of visit 2, visit 3, and visit 4) and (received adjuvant treatment in the first year) 4. Other (No recurrence or treatment): (PSA less than 0.2 at each of visit 2, visit 3, and visit 4) and did not receive adjuvant treatment
Quality of Life - EQ-5D-5L12 months and 24 monthsA comparison of the proportion of men achieving the best quality of life according to the EQ-5D-5L between intervention and control arms.
Functional Outcome - Urinary Continence3 monthsComparison of the continence at 3 months, measured using the ICIQ questionnaire between intervention and control arms. o Additional subgroup analysis: restricted to men who did not receive a pre-operative radiologist recommendation for bilateral nerve sparing The International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) assesses the frequency, severity, and impact of urinary incontinence. Total scores range from 0 to 21, with higher scores indicating more severe symptoms. Scores are calculated by summing 3 scored items. No subscales are used; higher values represent worse outcomes.
Oncological Outcomes - Positive Surgical MarginsAt the time of interventionDescriptive tabulation of PSM rates between NeuroSAFE RARP and standard RARP arms. PSMs will be grouped as: 1. Negative surgical margins 2. Small single positive surgical margin 3. Large or multifocal surgical margin
Health Economic Analysis12 months and 24 monthsUse of the Health Economics Questionnaires to inform a health cost analysis of NeuroSAFE RARP vs. standard RARP. * Economic analysis to assess healthcare resources use by arm and cost analysis to assess: * Cost of intervention and control * Cost of NHS resource use (medications, physiotherapy, * Cost of private health care resources (medication, physiotherapy) * Other private/societal costs (productivity losses, caregivers costs, out of pocket cost for transport, equipment)
Quality of Life - EQ-5D-5L Score12 months and 24 monthsAnalysis of EQ-5D-5L scores to produce QALYs at 12 months by arm

Countries

United Kingdom

Participant flow

Recruitment details

A total of 364 evaluable participants were required to have 80% power to detect such difference, with a two-sided α of 5%. Allowing for a 10% dropout rate, we aimed to recruit 404 participants (202 per group).

Pre-assignment details

A total of 364 evaluable participants were required to have 80% power to detect such difference, with a two-sided α of 5%. Allowing for a 10% dropout rate, we aimed to recruit 404 participants (202 per group).

Participants by arm

ArmCount
NeuroSAFE Procedure
These patients will undergo robotic radical prostatectomy with bilateral nerve spare.The pathologist will remove the pre-painted surface of the gland (which had been in contact with the neurovascular bundles) using a sharp blade.The tissue sample will be snap frozen and embedded in OCT.Using a cryostat, 10 micron thick slices will be placed on slides.The entire length of the area of interest will be sampled in this way generating ≈10 frozen sections per side.The slides will be stained with H&E and will be examined by a consultant pathologist.As soon as examination is complete the pathologist will telephone the operating surgeon to give the result.Presence of cancer cells at the margin of resection constitutes a positive margin and the neurovascular bundle on that side will be resected if the PSM is present in more than one slice on the same side or for a distance of 3 or more mm.
190
Control
These patients will undergo robotic radical prostatectomy with a nerve sparing procedure based on surgical planning performed by a consultant radiologist. The mp-MRI will be reviewed by a consultant radiologist along with the details of the prostate biopsy and DRE a decision to perform unilateral, bilateral or non-nerve sparing will be established and recorded in the clinical record form (CRF) for each patient.
191
Total381

Baseline characteristics

CharacteristicNeuroSAFE ProcedureControlTotal
Age, Continuous57.8 Years
STANDARD_DEVIATION 6.4
57.3 Years
STANDARD_DEVIATION 7
57.5 Years
STANDARD_DEVIATION 6.7
Baseline IIEF-5 Score23.3 units on a scale
STANDARD_DEVIATION 2.2
23.3 units on a scale
STANDARD_DEVIATION 2.5
23.3 units on a scale
STANDARD_DEVIATION 2.4
Baseline PSA9.1 Ng/ml
STANDARD_DEVIATION 6.5
8.6 Ng/ml
STANDARD_DEVIATION 5.9
8.9 Ng/ml
STANDARD_DEVIATION 6.2
BMI27.3 kg/m^2
STANDARD_DEVIATION 3.8
27.1 kg/m^2
STANDARD_DEVIATION 3.4
27.2 kg/m^2
STANDARD_DEVIATION 3.6
Cambridge Prognostic Group
1
6 Participants4 Participants10 Participants
Cambridge Prognostic Group
2
80 Participants83 Participants163 Participants
Cambridge Prognostic Group
3
38 Participants40 Participants78 Participants
Cambridge Prognostic Group
4
46 Participants44 Participants90 Participants
Cambridge Prognostic Group
5
7 Participants8 Participants15 Participants
Clinical T-Stage
T-1
7 Participants6 Participants13 Participants
Clinical T-Stage
T-2
135 Participants132 Participants267 Participants
Clinical T-Stage
T-3
38 Participants41 Participants79 Participants
Prostate volume38.1 cm^3
STANDARD_DEVIATION 17.6
39.7 cm^3
STANDARD_DEVIATION 20.1
38.9 cm^3
STANDARD_DEVIATION 18.9
Race/Ethnicity, Customized
Ethnicity
Asian
9 Participants9 Participants18 Participants
Race/Ethnicity, Customized
Ethnicity
Black
49 Participants53 Participants102 Participants
Race/Ethnicity, Customized
Ethnicity
Other/Mixed
5 Participants4 Participants9 Participants
Race/Ethnicity, Customized
Ethnicity
White
108 Participants103 Participants211 Participants
Sex: Female, Male
Female
0 Participants0 Participants0 Participants
Sex: Female, Male
Male
190 Participants191 Participants381 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
2 / 1902 / 191
other
Total, other adverse events
0 / 1900 / 191
serious
Total, serious adverse events
6 / 1905 / 191

Outcome results

Primary

Erectile Function

Comparison of the erectile function at 12-months according to allocated treatment arm (i.e. NeuroSAFE RARP \[intervention\] vs. standard RARP \[control\]). Erectile function is measured using the IIEF-5 questionnaire Measure Description: The International Index of Erectile Function-5 (IIEF-5) measures erectile dysfunction severity. Total scores range from 5 to 25, calculated by summing 5 items. Higher scores indicate better erectile function. Severity categories: 22-25 = no erectile disfunction, 17-21 = mild, 12-16 = mild to moderate, 8-11 = moderate, 5-7 = severe. No subscales are used; the total score is the sum of all items.

Time frame: 1 year

Population: Participants with available data

ArmMeasureValue (MEAN)Dispersion
NeuroSAFE ProcedureErectile Function12.7 units on a scaleStandard Deviation 8
ControlErectile Function9.7 units on a scaleStandard Deviation 7.5
Comparison: Normal linear regression model adjusted for recruitment site, participant's age, and IIEF-5 at baseline, in participants with available datap-value: <0.000195% CI: [1.62, 4.75]Regression, Linear
Secondary

Functional Outcome - Urinary Continence

Comparison of the continence at 3 months, measured using the ICIQ questionnaire between intervention and control arms. o Additional subgroup analysis: restricted to men who did not receive a pre-operative radiologist recommendation for bilateral nerve sparing The International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) assesses the frequency, severity, and impact of urinary incontinence. Total scores range from 0 to 21, with higher scores indicating more severe symptoms. Scores are calculated by summing 3 scored items. No subscales are used; higher values represent worse outcomes.

Time frame: 3 months

Population: Participants with available data

ArmMeasureValue (MEAN)Dispersion
NeuroSAFE ProcedureFunctional Outcome - Urinary Continence5.8 units on a scaleStandard Deviation 4.1
ControlFunctional Outcome - Urinary Continence7.4 units on a scaleStandard Deviation 5.2
p-value: 0.00695% CI: [-2.42, -0.41]Regression, Linear
Secondary

Functional Outcome - Urinary Continence at 6 Months

Comparison of the continence at 3 months, measured using the ICIQ questionnaire between intervention and control arms. o Additional subgroup analysis: restricted to men who did not receive a pre-operative radiologist recommendation for bilateral nerve sparing The International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) assesses the frequency, severity, and impact of urinary incontinence. Total scores range from 0 to 21, with higher scores indicating more severe symptoms. Scores are calculated by summing 3 scored items. No subscales are used; higher values represent worse outcomes.

Time frame: 6 months

Population: Participants with available data

ArmMeasureValue (MEAN)Dispersion
NeuroSAFE ProcedureFunctional Outcome - Urinary Continence at 6 Months4.5 units on a scaleStandard Deviation 4.2
ControlFunctional Outcome - Urinary Continence at 6 Months5.1 units on a scaleStandard Deviation 4.7
Secondary

Health Economic Analysis

Use of the Health Economics Questionnaires to inform a health cost analysis of NeuroSAFE RARP vs. standard RARP. * Economic analysis to assess healthcare resources use by arm and cost analysis to assess: * Cost of intervention and control * Cost of NHS resource use (medications, physiotherapy, * Cost of private health care resources (medication, physiotherapy) * Other private/societal costs (productivity losses, caregivers costs, out of pocket cost for transport, equipment)

Time frame: 12 months and 24 months

Secondary

Oncological Outcome

Oncological outcome will be classified into four categories according to the following definition: 1. PSA persistence : PSA≥0.2 at visit 2 2. Biochemical recurrence: (PSA less than 0.2 at visit 2) and (PSA≥0.2 at visit 3 or PSA≥0.2 at visit 4) 3. Early salvage treatment: (PSA less than 0.2 at each of visit 2, visit 3, and visit 4) and (received adjuvant treatment in the first year) 4. Other (No recurrence or treatment): (PSA less than 0.2 at each of visit 2, visit 3, and visit 4) and did not receive adjuvant treatment

Time frame: 12 months after surgery

Population: Participants with available data

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
NeuroSAFE ProcedureOncological OutcomePSA persistance7 Participants
NeuroSAFE ProcedureOncological OutcomeBiochemical recurrence10 Participants
NeuroSAFE ProcedureOncological OutcomeAdjuvant treatment8 Participants
NeuroSAFE ProcedureOncological OutcomeOther (no recurrence or treatment)157 Participants
ControlOncological OutcomeOther (no recurrence or treatment)174 Participants
ControlOncological OutcomePSA persistance5 Participants
ControlOncological OutcomeAdjuvant treatment2 Participants
ControlOncological OutcomeBiochemical recurrence7 Participants
Secondary

Oncological Outcomes - Positive Surgical Margins

Descriptive tabulation of PSM rates between NeuroSAFE RARP and standard RARP arms. PSMs will be grouped as: 1. Negative surgical margins 2. Small single positive surgical margin 3. Large or multifocal surgical margin

Time frame: At the time of intervention

Population: Participants with available data

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
NeuroSAFE ProcedureOncological Outcomes - Positive Surgical MarginsNegative124 Participants
NeuroSAFE ProcedureOncological Outcomes - Positive Surgical MarginsSmall single positive surgical margin40 Participants
NeuroSAFE ProcedureOncological Outcomes - Positive Surgical Margins>3 mm or multifocal positive surgical margin26 Participants
ControlOncological Outcomes - Positive Surgical MarginsNegative137 Participants
ControlOncological Outcomes - Positive Surgical MarginsSmall single positive surgical margin24 Participants
ControlOncological Outcomes - Positive Surgical Margins>3 mm or multifocal positive surgical margin30 Participants
Secondary

Quality of Life - EQ-5D-5L

A comparison of the proportion of men achieving the best quality of life according to the EQ-5D-5L between intervention and control arms.

Time frame: 12 months and 24 months

Secondary

Quality of Life - EQ-5D-5L Score

Analysis of EQ-5D-5L scores to produce QALYs at 12 months by arm

Time frame: 12 months and 24 months

Source: ClinicalTrials.gov · Data processed: Feb 21, 2026