Resection of Hepatic Metastases from Colorectal Cancer Biologic Perspectives

During the past decade the results of slightly fewer than 1000 resections of liver metastases from colorectal carcinoma have been analyzed, retrospectively reanalyzed, and reviewed. The following are confirmed conclusions: major liver resection can be performed safely (less than a 5% operative mortality rate); 20% to 25% of these patients are cured; no other regional therapy options have any curative potential. The following caveats are also obvious: most patients who are operated on are not cured; although predictors have been proposed to select patients most likely to benefit from surgery, none is discriminating in and of itself; most therapy questions in this group of patients have not been addressed in any formal way; surgery for isolated regionally recurrent colon and rectum carcinoma remains an important stopgap only until effective systemic therapy is discovered. This review of our own and other single and multi-institutional prospective and retrospective data will be framed by the following questions. (1) Does resection of liver metastases cure patients or simply select those who would have survived in the long-term without any therapy? (2) In the absence of any formalized, properly designed trial, how can one judge the benefit of resection? (3) Why do metastases recur only in the liver? (4) What new therapies should focus on the predominant secondary failure sites in the majority of patients who do not benefit from hepatic metastasis resection?