Evaluation of Percutaneous Cryotherapy in the Treatment of Plexiform Neurofibromas and Unresectable Neurofibromas in Neurofibromatosis Type 1

Inclusion Criteria:

• Age ≥18 years;
• Patient with neurofibromatosis type 1 according to NIH criteria ;
• Patient with a benign neurofibromatous lesion that is painful and/or generatesfunctional discomfort and is unresectable or with unacceptable scarring ;
• Neutrophils > 1 G/l in the 14 days prior to inclusion;
• Adequate coagulation test with normals values (as judged by the investigator);
• Signed and dated informed consent document indicating that the patient has beeninformed of all aspects of the trial prior to enrolment
• Covered by a medical insurance;

Exclusion Criteria:

• Patient treated with concomitant chemotherapy and/or targeted therapies ;
• Any contraindication to a percutaneous cryotherapy procedure, including the need forice formation within 1 cm of the spinal cord, brain or other critical nervestructures, bowel or bladder (unless active or passive thermal protective maneuversare performed);
• Patient with malignant neurofibroma or MPNST ; CT scan without abnormality and iftumor presents a max SUV T/F>1.5 ratio, targeted biopsy is required to confirm benignor malignant histology.
• Patient with neurofibroma in areas at risk for neurological sequelae;
• Patient with cold urticaria with history of angioedema;
• Any cognitive impairment or condition that may limit the use of numerical scales andquality of life questionnaires;
• Patient for whom follow-up does not seem feasible even in the short term;
• Participation in another clinical trial that may interfere with the evaluation of theprimary endpoint;
• Patient under tutorshio, curatorship or deprived of liberty;
• Pregnant or breast-feeding woman;
• Any contraindication to the performance of an MRI
• Patient with dysplastic neurofibroma