Background: Increasing evidence suggests significant disparity in colorectal cancer outcomes between black and white patients. Contributing factors may include advanced tumor stage at diagnosis, differences in treatment, more aggressive tumor biology, access to care, and patient comorbidity.
Hypothesis: Disparities in colorectal cancer outcomes exist despite similar objective measures of treatment.
Design and setting: Ten-year retrospective review of all patients with colorectal cancer using tumor registries at a city hospital (n = 83) and a university medical center (n = 585) in the same city. We assessed stage at diagnosis; curative surgical resection; use of adjuvant treatment; overall, disease-free, and stage-specific survival; and socioeconomic status. Patients with nonwhite, nonblack ethnicity (4% overall) were excluded. Differences in stage and treatments were compared using the chi(2) test, and median survival rates were compared using log-rank tests.
Results: Significantly more black patients were treated at the city hospital (53.0%) vs the university medical center (10.6%) (P<.001). No differences were identified in stage distribution or treatments received between hospitals or between black and white patients. Significantly worse survival was noted among patients treated at the city hospital (2.1 vs 5.3 years; P<.001) and among black patients treated at both institutions (city hospital: 1.4 vs 2.1 years, and university hospital: 3.2 vs 5.7 years; P<.001 for both). Disease-free survival rates showed similar significant reductions for black patients at both institutions. There was no association between survival and socioeconomic status at either institution.
Conclusion: The marked reductions in overall and disease-free survival for black patients with colorectal cancer do not seem to be related to variation in treatment but may be due to biologic factors or non-cancer-related health conditions.