• Age≥18 years;

• Histological confirmation of low grade ESS;

• Locally advanced or metastatic disease at diagnosis or patient experiencing a tumor effraction during hysterectomy;

• Treatment with aromatase inhibitors (Anastrozole or Exemestane or Letrozole ) initiated either: for at least 24 months (in patients with no residual disease or non-measurable disease at the last AI initiation) OR for at least 36 months (in patients with measurable disease at the last AI initiation);

• Disease must be controlled at the time of the randomisation (objective response or stable disease) by the aromatase inhibitor initiated either for at least 24 or 36 months

• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≤ 2

• Covered by a medical insurance;

• Signed informed consent prior to any study-specific procedure.