Prostate CancerVIOLETTENCT04582656
Efficacy Assessment of a Novel 3D Cartography-based Targeted Focal Microwave Therapy in Men With Localized Intermediate-risk Prostate Cancer
A study testing Targeted microwave ablation in people with Prostate Cancer, run by Koelis at 5 sites in 2 countries.
Trial summary
Multicenter, prospective, European, single-arm, open-label, 12-month follow-up clinical trial. The purpose of this study is to evaluate the efficacy of a 3D cartography-based targeted microwave ablation for the treatment of the index lesion in patients with intermediate risk prostate cancer. Read more about this study
- Who is it for?
- Ages 45 to 80 years, men only
- Conditions the study is for
- Prostate Cancer
- What is being tested?
- Targeted microwave ablation
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 76 participants
- Where
- 5 sitesin 2 countries
- Study dates
- 11 Feb 2021to 21 Aug 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 45 to 80 years
- Men only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patient aged from 45 to 80 years old
- Life expectancy >10 years at the inclusion time
- Patient diagnosed with an intermediate-risk prostate cancer, defined by:
- A T1c or T2a clinical stage
- A unique cancer focus of Gleason (3+4) (Grade Group 2). In addition to the index lesion intended for treatment, the presence of additional microfoci < 10mm on mpMRI, for which biopsies present no evidence of cancer or a Gleason score of 3+3, is accepted
- A PSA level <20 ng/mL
Show all 13Show fewer
- Cancer focus identified on a multiparametric MRI of the prostate no more than 3 months before inclusion
- Confirmation of the suspicion of cancer identified on the MRI with transrectal or transperineal targeted and systematic biopsies performed with the KOELIS TRINITY system (no more than 3 months before inclusion)
- Patient suitable for IV sedation or general anesthesia and focal microwave ablation
- No debilitating medical or psychiatric illness that would preclude giving informed consent or receiving optimal treatment and follow-up
- Known coagulopathy or bleeding disorders are controlled
- Free, informed and written consent, dated and signed before the enrollment and before any exam required by the trial
- Patient affiliated to social security regimen or beneficiary of such regimen for local regions
Who cannot join
- Past medical history of prostate surgery
- Past medical history of radiotherapy or pelvic trauma
- Past medical history of acute prostatitis
- Presently taking hormonal manipulation or androgen supplements.
- Past medical history of cancer in the 5 previous years, excluding a non-metastatic basal cell carcinoma of the skin
- Severe BPH-related urinary tract symptoms, defined by an IPSS score >18
Show all 16Show fewer
- Serious medical illness, including any of the following: uncontrolled congestive heart failure, uncontrolled angina, myocardial infarction, cerebrovascular event within 6 months prior to the screening visit
- Contraindications for MRI exam
- Extracapsular cancer extension or seminal vesicles or pelvic lymph node invasion suspected on prostate MRI
- Presence of two or more clinically significant cancer foci in the inclusion biopsy exam
- Presence of a clinically significant cancer with a Gleason score ≥8 (Grade Group ≥4)
- Tumor largest axis >15 mm on the prostate MRI
- Distance between the cancer focus and the apex <5 mm on the prostate MRI
- Distance between the cancer focus and the rectum <5 mm on the prostate MRI
- Patient already participating in an interventional clinical trial
- Patient protected by law
Trial locations and contacts
5 sites in 2 countries.
5 sites in 2 countries
France4 sites
Centre Hospitalier Universitaire de Bordeaux
Bordeaux, 33000
American Hospital of Paris
Neuilly-sur-Seine, 92200
Hôpital Cochin (Assistance Publique - Hôpitaux de Paris)
Paris, 75014
Urologie Nantes Clinique & Institut d'Urologie - Site Atlantis
Saint-Herblain, 44800
About this study
Official title: Prospective Multicenter Trial Assessing the Efficacy of a Novel 3D Cartography-based Targeted Focal Microwave Therapy in Men With Localized Intermediate-risk Prostate Cancer
Multicenter, prospective, European, single-arm, open-label, 12-month follow-up clinical trial. The purpose of this study is to evaluate the efficacy of a 3D cartography-based targeted microwave ablation for the treatment of the index lesion in patients with intermediate risk prostate cancer.
Read the detailed description
European and American guidelines recommend several therapeutic alternatives: radical surgical treatment, external beam radiotherapy or brachytherapy. However, whole-gland treatment induces significant morbidity and burden on quality of life. Targeted treatments of the index tumor are currently under investigation to decrease morbidity while proposing active treatment.
The purpose of this study is to assess the efficacy of a novel ablation treatment using microwaves, delivered transrectally or transperineally under real-time guidance with MRI-transrectal ultrasound image registration. The index tumor will be detected with prostate MRI and characterized with targeted biopsies using Organ Based Tracking (OBT) fusion with the TRINITY system (KOELIS, Meylan, France). The same system will be used to identify the index lesion and guide the targeted microwave ablation performed with the TATO3 device (Biomedical Srl, Florence, Italy).
All patients will undergo biopsy at 12 months of follow-up. A biopsy session will also be performed at 6 months, but only for patients with imaging results suspicious for cancer within the ablated area on the mpMRI.
- Conditions
- Prostate Cancer
- Being tested
- Targeted microwave ablation
- Keywords
- Cancer, Prostate, Targeted treatment, Microwave
- Medical subject headings
- Prostatic Neoplasms, Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Targeted microwave ablationDevice
Targeted ablation of the index tumor with microwaves, by using either a transperineal or a transrectal approach
| Study group | Role | What they receive |
|---|---|---|
| Targeted microwave ablation | Experimental | Targeted microwave transrectal or transperineal ablation of the prostatic index tumor using MRI-transrectal image registration and OBT fusion Receives: Device: Targeted microwave ablation |
What is being measured
The primary outcome is the main question the study is designed to answer.
The proportion of patients with no evidence of cancer on targeted biopsy
The proportion of patients with no evidence of cancer on targeted biopsy at 12 months, defined by a minimum of 2 targeted core biopsies taken from the index tumor site treated with microwave ablation for focal treatment of intermediate risk prostate cancer
Measured: 12 months
Secondary outcomes (21)
Proportion of radical salvage treatment
Proportion of patients undergoing radical salvage treatment of the index lesion
Measured: 12 months
Time to radical salvage treatment
Time to radical salvage treatment of the index lesion
Measured: 12 months
Proportion of patients with any cancer in the untreated area
Proportion of patients with any cancer in the untreated area, determined by a minimum 12 cores systematic biopsy
Measured: 12 months
Proportion of patients undergoing treatment for cancer in the untreated area
Proportion of patients undergoing treatment for cancer in the untreated area and time to treatment
Measured: 12 months
IPSS questionnaire
Changes in patients' reported outcome measures (PROMs) for urinary symptoms using IPSS score compared to baseline, score ranging from 0 to 35 (the higher the worse)
Measured: 7 days and 1, 6 and 12 months
IIEF-5 questionnaire
Changes in patients' reported outcome measures (PROMs) for erectile function using IIEF-5 score compared to baseline, score ranging from 5 to 25 (the lower the worse)
Measured: 7 days and 1, 6 and 12 months
MSHQ-EjD-SF questionnaire
Changes in patients' reported outcome measures (PROMs) for ejaculatory function and bother using MSHQ-EjD-SF score compared to baseline, score ranging from 1 to 15 (the lower the worse) for ejaculatory function and from 0 to 5 for bother/satisfaction (the higher the worse)
Measured: 7 days and 1, 6 and 12 months
Urine flow
Change in urine flow, using a uroflowmeter compared to baseline
Measured: 7 days and 1, 6 and 12 months
Adverse events
Number and severity of device and procedure related adverse events
Measured: 12 months
Patient post-operative pain level
Average patient post-operative pain level reported on a pain numeric rating scale, with a range from 0 (no pain) to 10 (worst pain ever)
Measured: Treatment day-evaluated between 2 and 4 hours after the procedure
Patient satisfaction
Patient satisfaction with the microwave ablation procedure as determined by questionnaire (no score assigned)
Measured: 1, 6 and 12 months
Ease of the procedure
Ease of the procedure measured with a score chosen by the operator (1: easy, 2: moderate, 3: difficult)
Measured: Day 1
Duration of the procedure and associated variables
Duration of the procedure and associated variables
Measured: Day 1
PSA
Change in PSA measurement compared to baseline
Measured: 1, 3, 6, 9 and 12 months
PSA Nadir
Time to PSA Nadir after treatment of the index lesion
Measured: 12 months
Prostate volume
Change in volume of the prostate on the mpMRI compared to baseline
Measured: 7 days and 6 and 12 months
Patient motivation
Characterization of patient motivation to undergo targeted microwave ablation for treatment of the index lesion, as assessed by patient questionnaire (no score assigned)
Measured: Baseline
Surgeon opinion regarding adequate guidance of the microwave ablation needle
To evaluate the adequate guidance of the microwave ablation needle by the surgeon opinion
Measured: Day 1
Adequate guidance of the microwave ablation needle on the treated index lesion
To evaluate the adequate guidance of the microwave ablation needle by percentage of covering of the treated index lesion
Measured: Day 1
Adequate guidance of the microwave ablation needle on the treated index lesion and margins
To evaluate the adequate guidance of the microwave ablation needle by percentage of covering of the treated index lesion and margins
Measured: Day 1
Learning curve of the TMA procedure
To evaluate the learning curve of the TMA procedure by the duration of the intervention (delay between probe in and the end of anesthesia (minutes).
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Oct 2020
- Study start11 Feb 2021
- Primary completion29 Jul 2025
- Study completion21 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Prostate CancerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Multicenter, single-arm, open-label, 12-month follow-up clinical trial
- Masking
- None (open label)
- Enrolment
- 76 participants (actual)
Sponsor and investigators
- Lead sponsor
- Koelis
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Roland VAN VELTHOVEN, MD, Study chair, Uro Science & Consulting
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04582656
- Sponsor's protocol ID
- VIOLETTE
- Other IDs
- 2019-A00803-54
- Acronym
- VIOLETTE
- Status last verified
- Mar 2026
- First submitted
- 29 Sep 2020
- Last updated
- 6 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Delongchamps NB, Peltier A, Potiron E, Bladou F, Diamand R, Messas A, Roche JB, Robert G, Hoepffner JL, Piechaud T, Anract J, Velthoven RV. Targeted microwave ablation of localised prostate cancer (VIOLETTE trial): a prospective multicentre study. BJU Int. 2026 Jun;137(6):1032-1039. doi: 10.1111/bju.70220. Epub 2026 Mar 11.
PubMed 41810596
Study at a glance
From the registry record, last updated by the sponsor on 6 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prospective Multicenter Trial Assessing the Efficacy of a Novel 3D Cartography-based Targeted Focal Microwave Therapy in Men With Localized Intermediate-risk Prostate Cancer
- ClinicalTrials.gov ID
- NCT04582656
- Acronym / sponsor ID
- VIOLETTE / VIOLETTE
- Conditions
- Prostate Cancer
- Keywords
- Cancer, Prostate, Targeted treatment, Microwave
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 76 participants (actual)
- Lead sponsor
- KoelisIndustry (pharma, biotech, devices)
- Study start
- 11 Feb 2021 (actual)
- Primary completion
- 29 Jul 2025 (actual)
- Study completion
- 21 Aug 2025 (actual)
- First posted
- 9 Oct 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Multicenter, prospective, European, single-arm, open-label, 12-month follow-up clinical trial. The purpose of this study is to evaluate the efficacy of a 3D cartography-based targeted microwave ablation for the treatment of the index lesion in patients with intermediate risk prostate cancer.
Detailed description
European and American guidelines recommend several therapeutic alternatives: radical surgical treatment, external beam radiotherapy or brachytherapy. However, whole-gland treatment induces significant morbidity and burden on quality of life. Targeted treatments of the index tumor are currently under investigation to decrease morbidity while proposing active treatment.
The purpose of this study is to assess the efficacy of a novel ablation treatment using microwaves, delivered transrectally or transperineally under real-time guidance with MRI-transrectal ultrasound image registration. The index tumor will be detected with prostate MRI and characterized with targeted biopsies using Organ Based Tracking (OBT) fusion with the TRINITY system (KOELIS, Meylan, France). The same system will be used to identify the index lesion and guide the targeted microwave ablation performed with the TATO3 device (Biomedical Srl, Florence, Italy).
All patients will undergo biopsy at 12 months of follow-up. A biopsy session will also be performed at 6 months, but only for patients with imaging results suspicious for cancer within the ablated area on the mpMRI.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Multicenter, single-arm, open-label, 12-month follow-up clinical trial
| Arm | Type | Receives |
|---|---|---|
| Targeted microwave ablation | Experimental | Device: Targeted microwave ablationTargeted microwave transrectal or transperineal ablation of the prostatic index tumor using MRI-transrectal image registration and OBT fusion |
Who may qualify
- Ages
- 45 to 80 years
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (13 listed)
- Patient aged from 45 to 80 years old
- Life expectancy >10 years at the inclusion time
- Patient diagnosed with an intermediate-risk prostate cancer, defined by:
- Cancer focus identified on a multiparametric MRI of the prostate no more than 3 months before inclusion
- Confirmation of the suspicion of cancer identified on the MRI with transrectal or transperineal targeted and systematic biopsies performed with the KOELIS TRINITY system (no more than 3 months before inclusion)
Key exclusion criteria (16 listed)
- Past medical history of prostate surgery
- Past medical history of radiotherapy or pelvic trauma
- Past medical history of acute prostatitis
- Presently taking hormonal manipulation or androgen supplements.
- Past medical history of cancer in the 5 previous years, excluding a non-metastatic basal cell carcinoma of the skin
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Targeted microwave ablationTargeted ablation of the index tumor with microwaves, by using either a transperineal or a transrectal approach | Device | Targeted microwave ablation |
Primary outcome
The proportion of patients with no evidence of cancer on targeted biopsy
Time frame: 12 months
The proportion of patients with no evidence of cancer on targeted biopsy at 12 months, defined by a minimum of 2 targeted core biopsies taken from the index tumor site treated with microwave ablation for focal treatment of intermediate risk prostate cancer
21 secondary outcomes
Proportion of radical salvage treatment
Time frame: 12 months
Time to radical salvage treatment
Time frame: 12 months
Proportion of patients with any cancer in the untreated area
Time frame: 12 months
Proportion of patients undergoing treatment for cancer in the untreated area
Time frame: 12 months
IPSS questionnaire
Time frame: 7 days and 1, 6 and 12 months
IIEF-5 questionnaire
Time frame: 7 days and 1, 6 and 12 months
MSHQ-EjD-SF questionnaire
Time frame: 7 days and 1, 6 and 12 months
Urine flow
Time frame: 7 days and 1, 6 and 12 months
Adverse events
Time frame: 12 months
Patient post-operative pain level
Time frame: Treatment day-evaluated between 2 and 4 hours after the procedure
Patient satisfaction
Time frame: 1, 6 and 12 months
Ease of the procedure
Time frame: Day 1
Duration of the procedure and associated variables
Time frame: Day 1
PSA
Time frame: 1, 3, 6, 9 and 12 months
PSA Nadir
Time frame: 12 months
Prostate volume
Time frame: 7 days and 6 and 12 months
Patient motivation
Time frame: Baseline
Surgeon opinion regarding adequate guidance of the microwave ablation needle
Time frame: Day 1
Adequate guidance of the microwave ablation needle on the treated index lesion
Time frame: Day 1
Adequate guidance of the microwave ablation needle on the treated index lesion and margins
Time frame: Day 1
Learning curve of the TMA procedure
Time frame: Day 1
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Apr 2026.
- Derived from this study: PubMed 41810596Delongchamps NB, Peltier A, Potiron E, Bladou F, Diamand R, Messas A, Roche JB, Robert G, Hoepffner JL, Piechaud T, Anract J, Velthoven RV. Targeted microwave ablation of localised prostate cancer (VIOLETTE trial): a prospective multicentre study. BJU Int. 2026 Jun;137(6):1032-1039. doi: 10.1111/bju.70220. Epub 2026 Mar 11.
- Individual participant dataSharing planned: No
Related trials for Prostate Cancer
Active, not recruiting
Streamlined Geriatric and Oncological Evaluation Based On IC Technology
Breast Cancer, Comorbidities and Coexisting Conditions
Active, not recruitingObservational study
MRI Fusion Biopsy vs. Micro-Ultrasound Guided Biopsy
Prostate Cancer
Enrolling by invitationObservational study
Natural History Study of Early Life Exposures in Agriculture (ELEA)
Prostate Cancer, Leukemia
Not yet recruitingPhase 1/2
STAR0602 With Nivolumab in Non Small Cell Lung Cancer and in Metastatic Castrate-Resistant Prostate Cancer, and STAR0602 Alone in Thymic Carcinoma
NSCLC, Non-Small Cell Lung Cancer
Recruiting
Rehabilitation and Sex Therapy to Optimize Recovery After Prostate Cancer Treatment
Prostate Cancer, Urinary Incontinence
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Roland VAN VELTHOVEN, MD study chair
Uro Science & Consulting
5 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Targeted microwave ablation in people with Prostate Cancer, run by Koelis at 5 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 13 inclusion and 16 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 5 sites in France, Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The proportion of patients with no evidence of cancer on targeted biopsy (time frame: 12 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04582656, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Apr 2026.