Santa Clara Valley Medical Center San Jose, California
Barnabas Yik, MD, Andrew D. Ho, MD; Santa Clara Valley Medical Center, San Jose, CA
Introduction: In recent years, the incidence and mortality of late-onset colorectal cancer (CRC) have declined, but at a slower rate for Hispanic males compared to non-Hispanic white (NHW) males. Studies suggest people of low socioeconomic status receive less chemo-radiation, possibly contributing to the survival disparity. As we continue to shed light on the disparities in late-onset CRC, little is known about the growing problem of early-onset CRC. We investigated if treatment and survival disparities also exist in early-onset CRC for Hispanic males and NHW males. Methods: We performed a retrospective analysis of early onset CRC cases in the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Database. We analyzed all male patients of Hispanic and NHW descent diagnosed before age 50 between the years 1990 to 2009. Cases with incomplete staging, histology or treatment data were excluded from the analysis. Cases were then divided into two equal time periods, 1990-1999 and 2000-2009. In each time period, we analyzed changes in demographics, staging, survival and treatment via t-tests and chi-squared analysis. Results: A total of 15,212 early-onset CRC cases were identified. The CRC incidence increased for both Hispanic and NHW in 2000-2009, with a significantly higher proportion of Stage 3 (Table 1). There was no significant difference in 3-year survival between Hispanics and NHW in 1990-1999 (64.9% vs 68.3%, p-val 0.153), but Hispanics exhibited significantly lower survival in 2000-2009 (66% vs 74.2%; p-val < 0.001) (Table 2). There were also changes in treatment across time periods, particularly in Stage 3. Hispanics initially received more chemo-radiation in 1990-1999, but received less surgery and chemo-radiation in 2000-2009 (Table 3). Discussion: In late-onset CRC, research has shown decreased use of chemo-radiation for Stage 2 and 3 rectal cancers in patients with lower socioeconomic status, possibly contributing to worse survival in Hispanics compared to NHW. We similarly found lower survival rates in Hispanics in early onset colorectal in recent years. This disparity is associated with less treatments for Hispanics in Stage 3 CRC, the stage with the largest increase in incidence. Given the well-known barriers to healthcare access for Hispanics in late-onset CRC, further investigation into ethnic disparities may help mitigate survival differences and improve overall outcome in early-onset CRC.
Table 1. Incidence and Staging for Early Onset Colorectal Cancer in Hispanics and Non-Hispanic Whites from 1990-1999 to 2000-2009
Table 2. 3 Year Survival for Early Onset Colorectal Cancer in Hispanics and Non-Hispanic Whites from 1990-1999 to 2000-2009
Table 3. Treatment Differences in for Early Onset Colorectal Cancer in Hispanics and Non-Hispanic Whites from 1990-1999 to 2000-2009
Disclosures: Barnabas Yik indicated no relevant financial relationships. Andrew Ho: Abbvie – Speaker's Bureau.