Racial differences in clinical, genomic, and survival outcomes in colorectal cancer.

Abstract

10593 Background: Racial differences influence colorectal cancer incidence, biology, and survival, but the clinical and genomic drivers remain unclear. This study evaluates race-based variation in clinical features, metastatic patterns, and key mutations in a large real-world cohort to improve risk stratification and promote equitable treatment. Methods: Clinical and genomic data were obtained from MSK-CHORD via cBioPortal, including patients identified as Asian, White, or Black. Variables were analysed in RStudio. Group differences were assessed using chi-square, Fisher’s exact tests, or Kruskal–Wallis. Survival was analysed with Kaplan–Meier and Cox models. Significance was set at p < 0.05. Results: Among 5,168 colorectal cancer patients (White 83.9%, Asian 8.8%, Black 7.4%), several clinical and genomic features varied. Age differed significantly (p < 0.001), with Asians and Blacks diagnosed younger (median 58 y vs. 61 y) than Whites. Gender distribution was similar (p = 0.303). MSI-instability varied (p = 0.0321), lowest in Asians (7.7%) and Blacks (8.3%), and highest in Whites (11.9%). Right-sided tumours differed (p < 0.001), being least common in Asians (23.7%) and most common in Blacks (40.8%). Stage at diagnosis was similar (p = 0.0961). TMB differed modestly (p = 0.042): 5.87 in Asians vs. 6.05 in Black and White patients. FGA showed similarly small variation (p = 0.046): 0.17 in Asians, 0.16 in Blacks, and 0.15 in Whites. Liver metastases varied by race (p < 0.001): Asians 52%, Blacks 66%, Whites 56%. Reproductive organ involvement differed (p = 0.012): Asians 25%, Blacks 27%, Whites 20%; all other metastatic sites showed no differences (p > 0.05). Overall survival varied significantly (p < 0.001), highest in Asians (71.6 months) and Whites (54.3 months) and lowest in Blacks (32.3 months); Asians had similar mortality risk to Whites (HR 0.94), whereas Blacks had higher risk (HR 1.44). Genomic variation was notable: KRAS (p = 1.6×10⁻⁷) was highest in Blacks (56.8%), TP53 (p < 0.001) was highest in Asians (81.5%), and BRAF (p = 0.0046) was lowest in Blacks (7.1%), with no other genes differing. Conclusions: Racial differences were evident across outcomes. Black patients had the highest KRAS mutations and worst survival; Asians had the highest TP53 rates and best survival; Whites had the most MSI-H tumours. Other clinical features were similar. These patterns suggest biologic differences relevant to risk and treatment.