Cytoreductive surgery and intraperitoneal chemotherapy versus systemic chemotherapy for colorectal peritoneal metastases: A randomised trial.

BACKGROUND: First-line treatment of isolated resectable colorectal peritoneal metastases remains unclear. This study (the Swedish peritoneal study) compares cytoreductive surgery and intraperitoneal chemotherapy (surgery arm) with systemic chemotherapy (chemotherapy arm). METHODS: Patients deemed resectable preoperatively were randomised to surgery and intraperitoneal 5-fluorouracil 550 mg/m(2)/d for 6 d with repeated courses every month or to systemic oxaliplatin and 5-fluorouracil regimen every second week. Both treatments continued for 6 months. Primary end-point was overall survival (OS) and secondary end-points were progression-free survival (PFS), and morbidity. RESULTS: The study terminated prematurely when 48 eligible patients (24/arm) were included due to recruitment difficulties. Two-year OS was 54% in the surgery arm and 38% in the chemotherapy arm (p = 0.04). After 5 years, 8 versus 1 patient were alive, respectively (p = 0.02). Median OS was 25 months versus 18 months, respectively, hazard ratio 0.51 (95% confidence interval: 0.27-0.96, p = 0.04). PFS in the surgery arm was 12 months versus 11 months in the chemotherapy arm (p = 0.16) with 17% versus 0% 5-year PFS. Grade III-IV morbidity was seen in 42% and 50% of the patients, respectively. No mortalities. CONCLUSIONS: Cytoreductive surgery with intraperitoneal chemotherapy may be superior to systemic oxaliplatin-based treatment of colorectal cancer with resectable isolated peritoneal metastases.(ClinicalTrials.gov nr:NCT01524094).