In patients with unresectable metastatic colorectal cancer (CRC) surgery has been traditionally reserved for palliation of bleeding, obstruction, perforation, and/or intractable pain. For 40 years, treatment with 5-Fluorouracil modulated by Leucovorin or Levamisole has remained fairly constant, and median overall survival of patients with advanced CRC treated with this regimen has remained 12 months. However, over this period of time, our ability to select patient subsets with limited hepatic, even pulmonary, metastasis that could benefit from surgical resection has improved considerably. Contemporary systemic therapy regimens incorporating both cytotoxic chemotherapeutic and biological agents have led to unsurpassed improvements in survival (median 20 months) for patients with advanced CRC [1,2]. Evidence-based practice management and quality improvement through consensus-driven treatment decision-making algorithms and clinical pathways have ushered into modern-day practice neoadjuvant protocols including multi-drug systemic therapy and interventional radiology procedures that enable staged liver resections for CRC metastases. These interventions have increased significantly the number of patients that are suitable candidates for surgical eradication of metastatic disease to the liver and offer some patients previously considered incurable a chance for cure. These data emphasize the imperative of multi-disciplinary treatment planning and delivery of quality cancer care through a working partnership of medical and surgical oncologists.
Unfortunately, similar advances in the management and outcomes of patients with peritoneal carcinomatosis of colonic origin have not been achieved. Until recently, these patients have been approached with therapeutic nihilism, largely because of the dismal prognosis these patients face with limited surgical and systemic therapeutic options. The current standard of practice for patients with CRC and peritoneal dissemination remains palliative systemic therapy; however, evidence-based treatment guidelines are lacking. Notwithstanding, there is a strong movement afoot to define a combined modality treatment approach incorporating cytoreductive surgery, regional peritoneal chemotherapy and systemic therapy for patients with limited peritoneal surface malignancy of colonic origin. Selected subsets of patients with peritoneal disease can be rendered disease-free surgically and may benefit further from systemic therapy delivered in an ''adjuvant'' setting. A recently published consensus statement proposed a clinical decision and combined modality treatment pathway for selected patients with limited peritoneal surface malignancy of colonic origin in the absence distant metastasis [3]. The Peritoneal Surface Oncology Group developed this treatment decision-making algorithm in response to a literature review identifying a subset of This article is a US Government work and, as such, is in the public domain in the United States of America.