Prospective, monocentric study aiming to identify factors involved in platinum based-chemotherapy resistance in patients with epithelial ovarian cancer (all stages).

Patients will receive treatment (platinum based-chemotherapy) according to the standard practices.

A prospective database and an associated biological collection will be performed during 5 years:

• For each patient: clinical, biological, epidemiological and therapeutic treatment data will be collected during the standard therapeutic care.
• Biological samples (blood samples, tumor biopsy specimens and ascites samples) will be collected for all patients. These samples will be collected at the same time as those taken in standard practice (no additional biopsy will be performed for the study).

Study participation of each patient will be 5 years.

Inclusion Criteria:

1. Age ≥ 18 years old
2. Epithelial ovarian cancer at initial diagnosis (all stages)
3. Curative treatment (exeresis surgery) not yet initiated excepted neo-adjuvant treatment
4. Indication of platinum based-chemotherapy
5. Patient affiliated to the french social security system
6. Patient must provide written informed consent prior to inclusion in the study and any study-specific procedure

Exclusion Criteria:

1. Non-epithelial ovarian tumor, borderline ovarian tumor
2. Patient with recurrent disease
3. Exploratory surgery not performed at the "Institut Universitaire du Cancer de Toulouse - Oncopole (IUCT-O)"
4. Pregnant or breastfeeding women
5. Any psychological, familial, geographical or sociological condition potentially preventing the medical follow-up and/or study procedures
6. Patient who has forfeited his/her freedom by administrative or legal award or who is under legal protection (curatorship and guardianship, protection of justice)