Pharmacologic Interaction Between Ifosfamide and Aprepitant in Treated Patients With Soft Tissue Sarcoma

Inclusion Criteria: 1. Age ≥ 18 years. 2. Anatomopathologic diagnosis of soft tissue sarcoma (localized, local recidive or metastatic). 3. Patient receiving doxorubicin and ifosfamide chemotherapy (treatment decided during Multidisciplinary consultation meetings) (neoadjuvant, adjuvant or palliative treatment). 4. Screening laboratory values must meet the following criteria: 1. Hemoglobin \> 9.0 g/dL, Neutrophils \> 1500/mm3, Platelets \> 100000/mm3 2. Creatinine clearance (MDRD formula) \> 60ml/min. 3. AST/ALT \< 2.5 x ULN (5 x ULN in patients with hepatic metastasis). 5. Evaluable disease (measurable per RECIST or not), if applicable. 6. Patient must provide written informed consent prior to any study specific procedures. 7. Patient affiliated to a Social Health Insurance in France. Exclusion Criteria: 1. Previous treatment with Ifosfamide. 2. Patient who has already started doxorubicin and ifosfamide treatment. 3. Any medical condition that can increase the patient's risk 1. Active infection 2. Active hepatitis or cirrhosis 3. Recipients of organ transplants or immunocompromised patients, including Human Immunodeficiency Virus (HIV) infection 4. Pregnant or breastfeeding women 5. Any psychological, familial, geographical or sociological condition which does not allow to respect the medical follow-up and/or compliance to study procedure 6. Patient protected by law