A Prospective Feasibility Study Evaluating Extracellular Vesicles Obtained by Liquid Biopsy for Neoadjuvant Treatment Response Assessment in Rectal Cancer

Prior treatment

• Contraindication to chemotherapy and / or radiotherapy
  • . Insufficient tumoral sample on initial rectal biopsy for performing molecular analysis of tumor by NGS.

Other illness

• Metastatic disease
  • . T1 stage tumor
• History of pelvic radiotherapy and chemotherapy
• Other concomitant cancer or history of cancer other than treated in situ cervix cancer or basal cell or squamous cell carcinoma

Lab values

• Pregnant woman, likely to be pregnant or breastfeeding
  • Symptomatic cardiac and / or coronary insufficiency
  • Severe renal impairment (creatinine clearance less than 30ml / min)
  • Full or partial deficiency in dihydropyrimidine dehydrogenase (DPD) (uracilemia ≥ 16 ng / ml)
  • Peripheral neuropathy\> grade 1
  • Treatment with St. John's Wort
  • Treatment with yellow fever vaccine
  • Treatment with prophylactic phenytoin
  • Treatment with sorivudine or its chemically analogues related, such as brivudine
  • Active infection or other serious underlying disease likely to prevent the patient from receiving treatment
  • Persons deprived of their liberty, or under measure of judicial protection (curatorship or guardianship) or incapable of giving their consent
  • Impossibility of submitting to the medical follow-up of the test for geographical, social or psychological reasons.

Other

• Tumor of the upper rectum (\> 10 cm from the anal margin)

• Adenocarcinoma of rectum histologically proven
• Location ≤ 10 cm from the anal margin
  • Stage T3T4, or T2 if low rectal cancer
  • With indication of radiochemotherapy alone or chemotherapy followed by chemoradiotherapy prior to total mesorectal surgery or transanal surgery
• No metastasis
• Operable patient
• Patient ≥ 18 years old
• Patient likely to receive radiation therapy and chemotherapy.
• No history of pelvic radiotherapy for any reason
• No history of chemotherapy unless it was more than 10 years ago
• Effective contraception for patients of childbearing age: male and non-menopausal women must agree to use two medically validated methods of contraception (one for the patient and the other for the partner) during treatment and less up to 6 months for men and 4 months for women after last treatment
• Patient information and obtaining free, informed and written consent, signed by the patient and his investigator.
• Affiliate subject or beneficiary of a social security scheme of a member country of the European Community (article L1121-11 of the Code of Public Health)