Racial disparities and the outcome of metastatic (met) colorectal cancer (CRC).

Abstract

373 Background: Over the past decade survival of patients (pts) with CRC has improved. Although, the mortality rate for CRC is lower in Hispanics (H) than Whites (W), the decrease in mortality has been smaller among H during this period. H are the largest and minority in U.S. and therefore it is important to explain the discordant improvement in their outcome from CRC. We conducted a retrospective review of our CRC pts to determine whether treatment (TX) related factors would explain the observed difference in the outcome. Methods: Data for pts treated with at least one cycle of chemotherapy (CT) in the first line setting for met CRC at Los Angeles County Hospital and Norris Cancer Center between 2004 and 2011 were collected. Pts, disease, and TX related factors were reviewed and included for analysis. H were compared to non-Hispanics (NH) including Asians (A), Blacks (B), and W as a group and to W. Descriptive statistics were used to describe the population and where appropriate chi-square, Wilcoxon, and log-rank tests were used for comparison between the groups. Results: A total of 190 pts, 53% H, 24% A, 10% B, and 13% W were included for analysis. The median age of the population was 55 (21-82) years. 72 % of pts had de-novo met disease. 47% of patients had left, 24% right sided, and 29% rectal cancer. One-third of the patients received bevacizumab in the first line setting. Median time (MT) from first symptom to presentation was 85 days (d); 87 d in H and 74 d in NH (P=0.57). MT from diagnosis to TX was 70 d; 72 d H and 69 d NH (P=0.79). The median time from first TX to progression (TTP) was 8.9 (95% CI: 9.9-12.9) months (m) in H, 11.5 m in NH (P=0.058), and 12.6 m in W (P=0.079). Median BMI was 25.6; 26.5 in H, 24.1 in NH (P=0.001). There was no significance statistical difference between site of the disease, type and number of cycles of CT among the groups. Conclusions: Despite similar access to care in H and NH in our cohort, TTP is shorter for H than NH and W. Although the P is nonsignificant in this small sample, the trend is intriguing. The results need to be confirmed in larger cohorts and prospective studies. Given that the TX for met CRC is mostly unchanged since 2004, the results suggest an inherent biological difference between H and NH with obesity playing a significant role in the outcome.