The purpose of this study is to evaluate whether a second-look laparoscopy, followed by peritonectomy, hyperthermic intraperitoneal chemotherapy (HIPEC) or systemic chemotherapy in case of peritoneal carcinosis, improves the overall survival of patients who have had radical resection of mucinous colorectal cancer.

Patients will be entered into the study after radical resection of mucinous colorectal cancer, and reevaluated by CT scan after 6 months. Patients with no evidence of disease will be randomized to receive either standard follow up, or to have a second look laparoscopy to evaluate for peritoneal carcinosis. After laparoscopy, those patients who do not have peritoneal carcinosis will continue with standard follow up. Patients with peritoneal carcinosis diagnosed by laparoscopy will be treated according to their peritoneal carcinosis index (PCI). For patients with PCI > 20, systemic chemotherapy will be given according to Italian Association of Medical Oncology (AIOM) guidelines. Patients with PCI < 20 will undergo peritonectomy and then receive intravenous chemotherapy immediately followed by HIPEC.

Inclusion Criteria:

• Histologic diagnosis colorectal adenocarcinoma
• Mucinous histotype
• Stage I-III
• Radical (R0) surgical resection of primary tumor
• CT scan with contrast showing no evidence of disease recurrence 6 months after primary surgery
• Age ≥ 18 ≤ 65 years
• Performance Status ECOG ≤1
• Normal hepatic, renal and hematologic function
• Adjuvant chemotherapy permitted
• Signed informed consent

Exclusion Criteria:

• Residual disease after surgical resection of primary tumor
• Distant metastasis
• Active systemic infection
• Chronic cardiovascular illness that would contraindicate abdominal dilatation with pneumoperitoneum
• Concomitant or previous malignancy with 5 years of surgical resection of primary tumor (except for adequately treated non-melanoma skin cancer and in situ cervical cancer)
• Pregnancy or lactation
• Refusal or incapability of providing informed consent
• Impossibility of complying with study schedules and follow-up