The concept of “Obstruction-Free Survival” as an outcome measure in advanced colorectal cancer management

Despite improvements in diagnosis, imaging, surgical technique and chemotherapeutic agents, the majority of patients with synchronous, or metachronous, metastatic abdominal cancer ultimately die from the disease. In the context of advanced cancer, peritoneal malignancy is a particular problem, whether primary peritoneal malignancy (for example peritoneal mesothelioma) or peritoneal metastases from gastro-intestinal tract cancers. An added distressing, and life limiting, aspect of peritoneal malignancy is that bowel obstruction is common and often a terminal event. Malignant bowel obstruction is devastating for patients and distressing for relatives and healthcare workers, as it is often impossible to effectively palliate by medical treatments, endoscopic stenting or by surgical intervention. The combination of intestinal colic, with an inability to eat and drink, combined with the general need for a permanent nasogastric tube has major detrimental effects on the final period of a terminal illness