Efficacy of Rapamycin in the Treatment of Cervico-facial Lymphatic Malformations

Inclusion Criteria: * Patient from 0 to 18 years of age, presenting with poly-cystic suprahyoid or mediastinal lymphatic. * with chronic pain or functional respiratory or swallowing impairment with a CDS score \< 8 * Curative treatment is not possible or associated with a high risk of morbidity ,mortality and functional and cosmetic impairment * Karnofsky Score (\> 10 years of age) or Lansky score (≤10 years of age) \> 50% * Biology * Neutrophils count≥1.0 x 109/L * Platelets count ≥ 100 x 109/L * Hemoglobin ≥ 8 g/dL * Bilirubin ≤ 1,5 ULN * Transaminases \< 2,5 ULN * Serum albumin ≥ 2 g/dL. * LDL cholesterol \<160 mg/dL * Triglycerides \< 150 mg/dL * Negative test of pregnancy if relevant * Social security affiliation * At least 2 months after a previous procedure on the malformation Exclusion Criteria: * Non-respect of inclusion criteria * Other immunosuppressive therapy or long-term general corticosteroid therapy without a 28-day washout period * renal failure * Liver failure * Digestive disease leading to rapamycin malabsorption * uncontrolled or severe infectious disease * Patients requiring treatment interfering with CYP3A4 isoenzyme (rifampicin, rifabutin, carbamazepine, phenobarbital, phenytoin) or inhibiting CYP3A4 isoenzyme's activity (ketoconazole, voriconazole, itraconazole, telithromycin, clarithromycin, Diltiazem, Verapamil, nicardipine, clotrimazole, fluconazole , troleandomycin, bromocriptine, cimetidine, danazol, protease inhibitors) -patients requiring treatment by cisapride and metoclopramide * Concomitant administration of mTOR inhibitor * Peanuts or soya allergy * Impossibility to receive informed consent * Absence of social security affiliation * refusal to sign consent * Ongoing pregnancy or breastfeeding * refusal to participate