Improving survival in metastatic colorectal cancer

Colorectal cancer (CRC) is now a common cancer in both the western and eastern countries. Apart from the regional lymph nodes, the next most common site for colorectal metastases is the liver. In the past, these patients, when treated solely with fluorouracil / leucovorin, would have an overall survival of 8 – 12 months only. With the advent of safer liver surgery and better chemotherapeutic agents, most doctors have the distinct impression that the outlook for patients with metastatic colorectal disease has improved over the last 10 years. Is this observation correct?

Researchers from the University of Texas M D Anderson Cancer Center and the Mayo Clinic performed a retrospective review of 2470 patients with metastatic CRC treated at the Mayo Clinic (n=856) and MD Anderson (n=1614) during the period 1990 to 2006 (J Clin Oncol, epub 2009 May 26). From 1990 to 1997, the median overall survival for patients with metastatic CRC was 14.2 months. However this improved to 29.2 months for the time period 2004 – 2006. The overall 5 year survival rates showed similar improvements, from 9.1% in the 1990 – 1997 period to 19.2% for the 2001 – 2003 period.

Overall Median Survival – 1998 to 2006

Overall 5-Year Survival Rates – 1998 to 2006

From 1990 to 2006, 231 patients had liver resection for metastatic CRC. Liver resections were performed with increasing frequency from 1998 and between 2000 and 2006 approximately 20% of patients had liver surgery. From 1998 to 2006, the 5 – year survival rate among patients who had undergone liver resection was different from those with unresectable disease. The 5 – year survival rate was 55.2% for resected patients compared to 19.5% for unresectable patients. The median overall survival for these 2 groups of patients was 65.3 months and 26.7 months respectively.

Survival analyses of patients with metastatic CRC who could not undergo liver surgery but treated with chemotherapy only, showed that the survival rates from 1998 to 2000 were not different from that before 1998. From 2001 to 2003, the survival rates improved only minimally but improved significantly for those diagnosed between 2004 and 2006.

In the last 5 years, newer chemotherapy drugs have made a difference to patients with metastatic CRC. It has improved overall survival and in some cases, can convert metastatic CRC into a ‘chronic’ condition. However, chemotherapy alone cannot provide a cure. If liver surgery can be performed, it can potentially provide a chance to cure. Even if it could not cure, liver surgery can significantly increase your survival time. While liver surgery is a very major operation, it is very safe when performed properly. Even though it is a big operation, it does not mean you will have a long hospital stay. Can you hazard a guess on the average length of hospital stay for someone undergoing liver surgery for metastatic CRC?

7 days!