Study of Circulating Tumoral DNA in Ovarian Cancer

• Assessment and development of circulating tumor DNA detection techniques [ Time Frame: 2 years ] [ Designated as safety issue: No ]
  Quantification of circulating tumor DNA in blood samples. Results expressed in number of samples where circulating DNA is present.
  
  

• Comparison of the detection techniques (PAP (pyrophosphorolysis activated polymerisation), BEAMing, NGS(Next sequencing generation) with regards to feasibility, robustness, sensitivity and cost. [ Time Frame: 2 years ] [ Designated as safety issue: No ]
  The methods of detection which will be used such as the BEAMing, the PAP(pyrophosphorolysis activated polymerization) and the NGS(next sequencing generation is techniques of a big specificity capable of detecting a mutant copy among 1.104 wild copies for the BEAMing, 2.109 for the PAP and 1.105 for the NGS. The sensibility of these techniques is limited by the quantity of genomic DNA which we can extract from the sample of blood.
  
  

Other: Blood sampling
30mL of peripherical blood will be collected specially for the study. It's an additional blood sampling compare to the normal follow up of the patient.

Technique development:

In a first step, the different available techniques will be evaluated for specificity and sensibility using serial dilutions of cell lines with or without TP53 mutation.

Validation:

The tumor DNA detection rate will be estimated from patient's blood with ovarian cancer.

The investigators will study 25 patients to obtain at least 15 patients bearing a TP53 mutation that could be characterized in the primitive tumor or metastasis. With those 15 patients, the investigators will determine the most sensitive technique and the best cost/efficiency ratio.