Inclusion Criteria:  Age >18 years Histological evidence of peritoneal metastases Primary colorectal cancer Surgical cytoreduction CC0 or CC1  Exclusion Criteria:  Patient who has not received at least 3 courses of pre and/or post cytoreduction chemotherapy Primitive appendicitis Unknown primitive Patient with incomplete CC2 and/or palliative surgery Patient opposed to the use of their data for research. Isolated local pelvic recurrence. Extraperitoneal metastases not resected or destroyed before or during cytoreduction. Patient opposed to the use of his/her data for research purposes