Abstract 779: Factors responsible for ethnicity-based survival rates of colorectal cancer patients in the state of Texas
Authors: Chavarria Gabriela , Fofana Demba , Tripathi Manish 
Published: July 2021

In this study, we investigate the main factors that affect survival rates of colorectal cancer (CRC) patients in the state of Texas with respect to race group. CRC is the second leading cause of mortality in the USA as per recent ACS data. The five-year survival rate of patients diagnosed with localized-stage disease is 90%, survival declines to 71% and 14% for patients diagnosed with regional and distant stages, respectively. Some of the factors associated with this disease that we examined in this study include insurance, treatment, poverty, gender, age, stage, and grade of the cancer. In addition, we studied any on-going improvement or decline in the survival for patients with colorectal cancer. We studied this across two time periods, which are 1995-2005 and 2006-2015. The survival time of colon cancer patients was studied from diagnosis time to a specified time. Tests, such as log-rank and chi-squared, logistic regressions, and Cox proportional hazards regressions were utilized to assess survival rates. A 194, 955 population-based colorectal cancer cohort was utilized, which consisted of 67.60% Caucasian, 12.76% African American, 17.52% Hispanic, and the remaining 2.12% of other race. A racial disparity is evident in the survival of CRC patients in Texas given that survival was the lowest for the African American with their hazard ratio being the highest (1.197). This might be due to the diagnosis at a later stage of the disease, as compared to other groups. The other factors studied here too play a role in the survival rates of CRC patients. Patients with Medicaid demonstrated the least survival, with a hazard ratio of 1.131. Age was also significant factor in the survival of CRC patients, since older patients

demonstrated lower survival rates. The stage and grade of cancer that indicated the lowest survival was Distant and Grade IV, with Hazards of deaths of 5.389 and 1.218, respectively. Patients who had chemotherapy as treatment had the lowest survival (1.081 hazard of death), while patients who had a surgery as a form of treatment had the highest survival (0.835 hazard of death). A trend with poverty and survival was also discovered. As the poverty index increased, deaths of CRC patients increased as well, which shows decrease in survival. Gender did not play a significant role when determining survival, given that their p-values were non-significant, but males presented a lower survival. Overall, there was a decline in the survival of colorectal cancer patients across both periods before mentioned among the races/ethnicities studied. This study will provide a succinct overview of the disease and the factors responsible for the differential survival rates based on race.

Citation Format: Gabriela Chavarria, Demba Fofana, Manish Tripathi. Factors responsible for ethnicity-based survival rates of colorectal cancer patients in the state of Texas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 779.