Research Activities February 2013, No. 390
More research needed to compare therapies for colorectal cancer metastases is to the liver
A new research review concludes that in patients with liver metastases from colorectal cancer, there is not enough evidence available to compare the effectiveness of local liver therapies when surgery is not an option. Not only is colorectal cancer the fourth most frequently diagnosed cancer and the second leading cause of cancer death in the United States, it is also the most common cancer that spreads to the liver. Therapies that target the liver are used with the goal of reducing the symptoms of the disease and/or extending the survival of these patients.
The review by the Agency for Healthcare Research and Quality (AHRQ) describes several types of therapies that target colorectal cancer that has spread to the liver in two different types of patients who are not candidates for surgery—those with most of the disease in their liver who are also receiving chemotherapy, and those who are not eligible for continued chemotherapy because the disease has progressed during treatment.
The therapies addressed in the review that target the liver include ablation (destruction of tissue by heating or cooling), embolization (blocking blood vessels that feed the cancer), and radiotherapy (directed radiation to destroy cancer cells). There are also extensive gaps in the research, even when looking at critical benefits or harms, and the quality of the available studies is generally low. A patient registry is one tool for future research that may generate ideas for clinical trials that can further test the effectiveness of these therapies.
These findings are available in the research review Local Hepatic Therapies for Metastases to the Liver From Unresectable Colorectal Cancer that can be found on AHRQ's Effective Health Care Program Web site at http://www.effectivehealthcare.ahrq.gov.