Racial/ethnic disparities in early-onset colorectal cancer: implications for a racial/ethnic-specific screening strategy.

Introduction: Early-onset colorectal cancer (EO-CRC) is a public health concern. Starting screening at 45 years has been considered, but there is discrepancy in the recommendations. Racial disparities in EO-CRC incidence and survival are reported; however, racial/ethnic differences in EO-CRC features that could inform a racial/ethnic-tailored CRC screening strategy have not been reported. We compared features and survival among Non-Hispanic White (NHW), Non-Hispanic Black (NHB), and Hispanics with EO-CRC.

Methods: CRC patients from SEER 1973-2010 database were identified, and EO-CRC was defined as CRC at <50 years. Clinical/pathological features and survival were compared between NHW, NHB, and Hispanics. Cancer-specific survival (CSS) predictors were assessed in a multivariable Cox proportional hazard model.

Results: Of 166,416 patients with CRC, 16,545 (9.9%) had EO-CRC. The EO-CRC frequencies in NHB and Hispanics were higher than NHW (12.7% vs. 16.5% vs. 8.7%, p < 0.001). EO-CRC in NHB presents more frequently in females, with well/moderately differentiated, stage IV, and is less likely to present in locations targetable by sigmoidoscopy than NHW (54.6% vs. 67.7% OR:1.7, 95% p < 0.001). 5-year CSS was lower in NHB (59.4% vs. 72.8%, HR: 1.7; 95% CI: 1.54-1.82) and Hispanics (66.4% vs. 72.8%, HR: 1.3; 95% CI: 1.16-1.39) than NHW. A regression model among patients with EO-CRC showed that being NHB or Hispanic were independent predictors for cancer-specific mortality, after adjusting for gender, grade, stage, and surgery.

Conclusion: EO-CRC is more likely in NHB and Hispanics. Racial disparities in clinical/pathological features and CSS between NHB and NHW/Hispanics were evidenced. A racial/ethnic specific screening strategy could be considered as an alternative for patients younger than 50 years.