The primary objective: association study of characteristics of tumoral microenvironment and immunity of digestive cancers with patients' overall survival (OS).

The study aims to explore relationship between the molecular subgroups (DNA and RNA analysis), tumor microenvironment, host (immunity system, premetastatic niche, microbiota, metabolism) and survival (prognostic value), response (predictive value) and tolerance (toxicities) to conventional treatments or immunotherapies in digestive cancers, in particular, in colorectal cancer and pancreaticobiliary cancer.

This is a prognostic monocentric study which includes 2 parts:

• one retrospective observational cohort for which 150 eligible patients (who have being diagnosed between 1998 to 2020) will be entered in the cohort per year during 22 years targeting 3300 patients and
• one prospective interventional cohort in which 3000 patients (diagnosis will be done between 2020-2030) will be enrolled during 10 years. 10 years of follow-up for all patients. This cohort is non comparative, non randomized, non control.

The enrollment will last 10 years in Digestive Surgery Department, Ambroise Paré Hospital, APHP.

There is any change in management of patients' care who will participate to the study, all of the treatment modalities (i.e. surgery, chemotherapy, radiotherapy, immunotherapy, intra-arterial treatments and supportive care) are possible and choice of treatment will be made by investigator physician, after multidisciplinary meeting validation, and according to referential and recommendations of practice in department.

Statistic analysis

The statistic analysis will be performed and reported according to the international guidelines STROBE for the observational studies.

Inclusion Criteria:

• Carcinoma of colorectal, pancreatic, biliary tract or gastro-oesophageal, or neuroendocrine digestive tumors with cytologically or histologically proven, regardless of the stage;
• Diagnosis between 1998 and 2030;
• Be >/= 18 years;
• Have obtained signed informed consent (exemption for dead patients);
• Affiliated to the French social security - welfare system in France (CMU included).

Exclusion Criteria:

• Patient under tutoraship or curatorship;
• Foreign patient under AME schema, a medical help from the state in France;
• Pregnant or breastfeeding women (for prospective study);
• Any clinical, psychological or social reason which should influence patient compliance with protocol, according to investigator;
• Patient refusal.