ctDNA in CRC Patients Undergoing Curative-intent Surgery for Liver Metastases

Prior treatment

• Has no more than two surgical procedures planned for complete resection of primary tumor and/or liver metastases,
• Has deficient mismatch repair (dMMR)/ microsatellite instability (MSI) tumors treated with immunotherapy,
• Blood samples cannot be collected if surgical procedure,

Other illness

• Had more than 9 pre-operative cycles of chemotherapy for treatment of metastatic disease planned at inclusion,
• Has history of another primary cancer within the last 5 years, with the exception of non-melanomatous skin cancer and carcinoma in situ of the cervix,
• Cannot be followed-up due to geographical, social, or psychic conditions,
• Has medical or psychiatric condition or occupational responsibilities that may preclude compliance with the protocol,

Other

• The patient will be excluded if:
• Has definitively unresectable CLRM,
• Has not resected primary rectal tumor (low and middle),
• Is pregnant or breastfeeding,
• Is under guardianship, curatorship, or under the protection of justice.

• The patient will be included if:
• Has signed informed consent form and is willing to comply with all study procedures and availability for the study duration,
• Is ≥ 18 years of age,
• Has histologically confirmed colorectal adenocarcinoma,
• Has resected primary tumor or is eligible to primary tumor and CRLM (in case of synchronous metastases) resection within 6 months prior to study inclusion,
• Has isolated CRLM that is deemed resectable or potentially resectable (extrahepatic metastases excluded, except infracentimetric non-specific lung lesions with largest diameter \<1 cm and maximal number of ≤3) as judged by a multidisciplinary team meeting (based on CT scans of chest, abdomen, and pelvis \[or MRI if CT not possible\]),
• Is eligible to surgical procedure,
• Is fit for the chemotherapy-surgery combination treatment,
• Is registered in a national health care system (Protection Universelle Maladie \[PUMa\] included).