Therapeutic efficacy of systemic therapy for colorectal peritoneal carcinomatosis: surgeon’s perspective

Abstract Treatment choices for colorectal peritoneal carcinomatosis/metastases include systemic therapy and increasingly cytoreductive surgery with intraperitoneal chemotherapy delivery. These options are best considered as complementary and not exclusive alternatives. Two prospective randomized trials support use of peritonectomy procedures and intraperitoneal chemotherapy for colorectal peritoneal carcinomatosis. This overview examines efficacy, limitations and landscape of systemic therapy focusing on colorectal peritoneal carcinomatosis. Observations from literature support notions that (1) systemic therapy provides survival benefit for all prototypical patients with mCRC irrespective of metastatic disease site; (2) the magnitude of this benefit is considerably reduced among patients with peritoneal metastases who consequently experience significantly shorter overall survival; (3) efficacy of systemic therapy improved over time but at a slower pace for those with carcinomatosis; (4) this therapeutic difference has not diminished with introduction of targeted therapy, but perhaps widened; (5) further research of cytoreductive surgery and/or intraperitoneal regional therapies is thus a multidisciplinary responsibility of the entire oncology community; (6) peritonectomy procedures with intraperitoneal regional therapy are not scientifically supported in absence of systemic therapies.