Survival after hepatic resection of colorectal cancer metastases: a national experience

Background — Most estimates of short term and long term survival after hepatic resection of colorectal cancer metastases are derived from surgical case series. We used Medicare data to investigate operative mortality and long term survival in a national sample and looked at factors associated with survival.

Methods — We analyzed data for Medicare enrollees (age ≥ 65) admitted to hospital between January 1, 2000 and December 31, 2004 with a primary diagnosis of colorectal cancer with resection. We restricted the sample to those who subsequently underwent hepatic resection for liver metastases. We used the Medicare denominator file to determine operative mortality and long term survival and the factors that are associated with these outcomes.

Results — Of the 306061Medicare beneficiaries diagnosed with colorectal cancer, we identified 3957 patients who underwent hepatic resection for liver metastases. Crude 30-day mortality and 90-day mortality were 4.0% and 8.2%. The 5-year survival rate was 25.5%. Advancing age (HR=1.83; 95% CI 1.32, 2.53 for age 80 and old vs age 65–69), comorbid disease (HR=1.40; 95% CI 1.06, 1.85 for Charson 5+ vs Charlson 0) and synchronous colon/hepatic resection (HR=2.46; 95% CI 1.89, 3.20 for Synchronous vs Metachronous ) were associated with worse 90 day mortality. Likewise, long term mortality was also associated with age (HR =1.36; 95% CI 1.18, 1.56), comorbid disease (HR = 1.51; 95% CI 1.36, 1.69 and synchronous colon/hepatic resection (HR=1.37; 95% CI 1.24, 1.51 for synchronous vs metachronous).

Conclusion — In this national study, short and long term survival is worse than that reported in surgical case series. Subgroups at high risk for worse outcomes include the extreme elderly and those undergoing synchronous colon and hepatic resection.