Percutaneous Radiofrequency Ablation of Parietal Endometriosis (PRFA) (PRFA)

Parietal endometriosis is the implantation of endometrial tissue in abdominal structures more superficial than the peritoneum. It is a rare form of the disease (incidence estimated between 0.04 and 12% among women operated on for endometriosis depending on the series) but is classically resistant to medical treatment and can be disabling. Surgical resection is currently the reference treatment in the event of failure of hormonal treatment, despite the sometimes significant skin scars and the risk of parietal fragility that may require a cure of venting by parietal prosthesis. The recurrence rate after surgical resection is 4.3%. The use of radiofrequency for therapeutic purposes is nowadays described in multiple applications such as cardiac arrhythmia, neurological and spinal disorders, as well as for the treatment of liver, kidney, prostate, breast, lung or skin cancers. Its use has already been reported in the field of benign gynecology with, in particular, demonstrated efficacy in the treatment of uterine fibroids by laparoscopic, trans-vaginal or percutaneous means. There are also large published series on radiofrequency for the treatment of adenomyosis, by the transvaginal and laparoscopic route. In the context of parietal endometriosis, this would be a minimally invasive, percutaneous treatment. Ultrasound guidance allowing good targeting of the lesions and the procedure would most often be carried out on an outpatient basis and under local anaesthesia. And in case of failure or partial effectiveness, the reference treatment would remain accessible for these patients. There is only one published case of the use of radiofrequency in parietal endometriosis (case reports). Despite results that seem encouraging in terms of a rapid and prolonged therapeutic effect on symptoms, no further cases or series have been published since. Our study aims to investigate the feasibility of percutaneous radiofrequency treatment for parietal endometriosis, with the secondary objective of evaluating the safety, efficacy and risk factors for failure of the technique. 10 patients will be treated. For follow-up all patients will have an ultrasound and MRI before treatment, then an ultrasound at 1 month, 3 months and 6 months post-treatment and a second MRI at 6 months post-treatment. The investigators will also evaluate pain and quality of life with specific questionnaires at each visit.

Treatment is carried out under local anaesthesia after surgical asepsis, in interventional radiology room. Radiofrequency needles are inserted percutaneously under ultrasound guidance. Number of needles depends on the size of lesion (1 or 2 or 3 needles). In case of proximity between lesion and peritoneum, artificial ascites can be performed. Treatment is carried out in accordance with device's instructions for use (thyroid nodules treatment algorithm), with a gradual increase in power every 5 minutes, without exceeding the maximum authorised power (depending on number and length of needles). State of coagulation is monitored under visual ultrasound control of ablation area (diffusion of Co bubbles), until a decrease in effective power is obtained. Several ablation zones are performed on the same nodule with overlapping of the different impacts. An ice pack is applied to the treated area. An analgesic PO treatment of step 1 and/or 2 is prescribed for 5 days.

Feasibility of PRFA. Evaluation by composite criteria with the need to validate all the criteria for the procedure to be considered "feasible".

The treatment is considered "feasible" if it meets all of the following criteria: Visualization of the lesion intraoperatively by percutaneous ultrasound (yes/no), Visibility of the posterior aponeurosis/peritoneum interface behind the lesion (yes/no), Placement of one or more radiofrequency (RF) needles within the target lesion (yes/no), Procedure for firing without anomaly (yes/no) : Performing one or more treatment zones until a drop in effective power is obtained, automatically interrupting needle activity and demonstrating the effectiveness of the treatment. complete covering of the nodule by the CO bubbles released by the procedure.

Number, type and severity of adverse events related to radiofrequency treatment. Pain during treatment.

From the 1st visit (no later than 7 days before treatment (Day -7)) until the end of the study (Month 6)

Diameters (largest, orthogonal to the largest diameter and anteroposterior diameter [in cm]) and volume (in cm3) of the lesions, Echogenicity to muscle (hypo- / iso- / hyper-echoic) Presence of a posterior shadow cone (yes/no) Sonovue characteristics (no, moderate or frank enhancement) US Doppler characteristics (no, slight or marked vascularization) Characteristics in Shearwave elastography (in kPa) Evaluation by the radiologist of the percentage of nodule volume presenting a change in appearance on ultrasound (0% / < 50% / > 50% / 100%)

Diameters (largest, orthogonal to the largest diameter and anteroposterior diameter [in cm]) and volume (in cm3) of the lesions, Echogenicity to muscle (hypo- / iso- / hyper-echoic) Presence of a posterior shadow cone (yes/no) Sonovue characteristics (no, moderate or frank enhancement) US Doppler characteristics (no, slight or marked vascularization) Characteristics in Shearwave elastography (in kPa) Evaluation by the radiologist of the percentage of nodule volume presenting a change in appearance on ultrasound (0% / < 50% / > 50% / 100%)

volume (in cm3) of the lesions, Echogenicity to muscle (hypo- / iso- / hyper-echoic) Presence of a posterior shadow cone (yes/no) Sonovue characteristics (no, moderate or frank enhancement) US Doppler characteristics (no, slight or marked vascularization) Characteristics in Shearwave elastography (in kPa) Evaluation by the radiologist of the percentage of nodule volume presenting a change in appearance on ultrasound (0% / < 50% / > 50% / 100%)

Diameters (largest, orthogonal to the largest diameter and anteroposterior diameter [in cm]) and volume (in cm3) of the lesions signal in T2 sequence with respect to the muscle (hypo- / iso- / hyper-signal) ; presence of T1 hypersignal (yes/no); minimum and maximum ADC (Apparent Diffusion Coefficent) value (in mm²/s); lesional enhancement in the center (yes/no); Peri-lesional enhancement (yes/no);

Assessment of pain related to the lesion: maximum EVA during menstruation and maximum EVA outside of menstruation

Quality of life of patients measured by validated questionnaire in endometriosis: SF36 (Short Form (36) Health Survey)

Quality of life of patients measured by validated questionnaire in endometriosis: EHP-5 (Endometriosis Health Profile)

Assessment of pain related to the lesion: maximum EVA during menstruation and maximum EVA (Echelle Visuelle Analogique) outside of menstruation

Assessment of pain related to the lesion: maximum EVA during menstruation and maximum EVA outside of menstruation

age, gestational age, parity, history of caesarean section, history of gynaecological surgery excluding endometriosis, history of endometriosis surgery, age of diagnosis of endometriosis, age of diagnosis of parietal endometriosis.

Inclusion Criteria: Patient over 25 years of age; Presenting between 1 and 3 lesions of parietal endometriosis, all accessible to radiofrequency treatment, with a major axis less than 10cm; Symptomatic (chronic and/or catamenial pain); Histological diagnosis of endometriosis; In failure of medical treatment; Nodule visible on ultrasound; Affiliated with or beneficiary of a social security or similar scheme. Having signed an informed consent for participation in the study Exclusion Criteria: Presence of a parietal endometriosis lesion with superficial skin involvement (dermis); Presence of other symptomatic extra-parietal endometriosis lesions for which surgical treatment is planned; Uncontrolled diabetes, i.e. HbA1c >7% despite well-treated and well-controlled treatment; Contraindication to the use of radiofrequency: implanted electronic device, such as a pacemaker or self-synchronizing defibrillator; weakened immune system; coagulation disorder; Contraindication to the use of Sonovue Contraindication to the use of gadolinium Severe renal failure (glomerular filtration rate less than 30 ml / min / 1.73m²) Pregnant patient or with a desire to become pregnant within 6 months after treatment; Patient who is not fluent in the English language; Patient over the age of majority protected by law, under curatorship or guardianship; Person deprived of liberty by a judicial or administrative decision, person subject to psychiatric care and people admitted to a health or social establishment for purposes other than that of research. Patient participating in other interventional research that may interfere with the present research (at the discretion of the investigator); Patient who has participated in other research that includes an ongoing opt out period.