The negative prognosis associated with KRAS mutation status in colorectal cancer (CRC) may be linked to race/ethnicity, according to the results of a population-based study presented at the 2021 Gastrointestinal Cancers Symposium. Specifically, mutant KRAS status was found to be associated with worse cause-specific survival compared with wild-type KRAS among non-Hispanic White and non-Hispanic Black patients, but not those of other race/ethnicities.
Jeffrey Bien, MD, of Stanford Medicine, and colleagues reviewed data from 202,237 patients from the Surveillance, Epidemiology, and End Results (SEER) registry who had been diagnosed CRC with 2010 and 2015. Just under one-tenth (9%; n=18,248) of patients in the registry had KRAS status available.
There was a higher rate of KRAS mutation in tumors from non-Hispanic Black patients (48%) or Hispanic patients (44%) compared with tumors from non-Hispanic White patients (39%) or Asian or Pacific Islander patients (37%; P <.01).
The researchers assessed the impact of mutant KRAS compared with wild-type KRAS in each race/ethnic group. For non-Hispanic White patients, there was a 7% risk increase for cause-specific survival associated with mutant status compared with wild-type status (HR, 1.07; 95% CI, 1.02-1.12). This more than doubled (15%) for non-Hispanic Black patients (HR, 1.15; 95% CI, 1.04-1.26). No significant differences were found for Asian Pacific Islanders.
Among all patients with wild-type KRAS, non-Hispanic Black patients and Hispanic patients still experienced higher mortality risk vs the non-White Hispanic population, the investigators noted. The risk of cause-specific survival was found to be 11% higher among non-Hispanic Blacks (HR, 1.11; 95% CI, 1.00-1.23) and 14% higher for Hispanics (HR, 1.14; 95% CI, 1.02-1.26) compared with non-Hispanic Whites. There was no increased risk for Asian Pacific Islanders (HR, 1.03; 95% CI, 0.91-1.16).
“The supposition of a KRAS mutation serving as a negative prognostic marker may be linked through race/ethnicity,” Bien concluded.
Bien J, Aljehani M, Lee JSH, Lin AY. Racial disparity in KRAS mutation frequency and outcomes in colorectal cancer (CRC): a U.S. population based study. Presented at: Gastrointestinal Cancers Symposium; January 15-17, 2021. Abstract 18.
This article originally appeared on Cancer Therapy Advisor