Survival and symptomatic benefit from palliative primary tumor resection in patients with metastatic colorectal cancer: A review

Background and aims: Patients with metastatic colorectal cancer have a limited life expectancy and are at risk for life-threatening tumor-related obstruction, perforation, and hemorrhage. Though surgical resection is performed frequently in this setting, its true benefit is not well-established. Materials and methods: We reviewed the medical literature from 1996-2006 using the search terms metastatic colorectal cancer and primary resection to find studies that evaluated the management of primary tumors in metastatic colorectal cancer. All search results were included in our analysis and were assessed on the basis of methodologic quality. Results/findings: Twelve relevant studies were identified; ten were single-institution retrospective reviews and two were population-based studies using National Cancer Institute's Surveillance, Epidemiology, and End-Results database. No prospective or randomized studies were identified. Approximately 70% of patients diagnosed with metastatic colorectal cancer in the USA undergo primary tumor resection; only a minority have this done for tumor-related symptoms or as part of potentially curative resection. The postoperative mortality ranged from 9.0-11.2% in large cancer registries but was often lower in major cancer centers. Resection of asymptomatic primary tumors was frequently associated with prolonged survival but was not found to reduce significantly the incidence of life-threatening tumor-related complications. Interpretation/conclusion: Retrospective data suggest that non-curative resection of asymptomatic colorectal primary tumors may prolong survival; however, selection bias and unaccounted clinical factors may explain this observation. Prospective, randomized surgical trials are needed to test the role of primary tumor resection in this setting, especially because of its current widespread use, and its associated cost, morbidity, and high postoperative mortality.