Disparities in resection of hepatic metastases in colon cancer.

Background: Evidence suggests that resection of synchronous hepatic metastases (SHM) in stage IV colon cancer is safe and can improve survival in select patients. Little is known, however, about the use of hepatic resection in this setting on a population level. The aim of this study was to describe trends in resection rates of SHM in patients with stage IV colon cancer using a large national cohort database.

Methods: A retrospective cohort study was performed of stage IV colon cancer patients during 2000-2011 in Surveillance, Epidemiology and End Results (SEER) Medicare data who had diagnosis codes confirming SHM. Univariate and multivariate logistic regression were used to identify patient factors related to receipt of hepatic resection.

Results: There were 11,351 patients with colon cancer and SHM. Of these patients, 465 (4.1%) underwent surgical hepatic resection. The proportion increased steadily over time from 2000-2002 (3.5%) to 2009-2011 (5.1%) (P=0.03). Patients who were older with higher comorbidity burden were less likely to undergo hepatic resection. Additionally, the odds of hepatic resection were 30% lower for African-American patients than for white patients (OR 0.70, P=0.05). Odds of hepatic resection were 44% lower for patients from ZIP Codes with >20% poverty than for patients from areas with <5% poverty (OR 0.56, P<0.001). Interestingly, among patients who underwent no surgical treatment at all, only 25% saw a surgeon after diagnosis. This number increased over time from 21.6% in 2000 to 29.1% in 2011 (P<0.001). Similar disparities noted above were seen with surgical evaluation for hepatic resection.

Conclusions: Despite evidence supporting the safety and efficacy of hepatic resection in the setting of SHM, few patients are seen by surgeons and go onto receive hepatic surgery. Additionally, access to hepatic resection is notably lower for African Americans and patients from areas with higher poverty rates.