Background: Ethnic/racial disparities in colorectal cancer (CRC) survival have been well documented. In Puerto Rico (PR), CRC is the leading cause of cancer death in men and women. This study reports the 5-year relative survival of Puerto Rican Hispanic (PRH) CRC patients compared to other US racial/ethnic groups and estimates the mortality hazard ratio by sex, age, and tumor stage at diagnosis.

Methods: CRC incidence data from subjects >50 years was obtained from the Puerto Rico Central Cancer Registry from January 1, 2001 to December 31, 2003. CRC incidence and mortality data for US Hispanics (USH), non-Hispanic White (NHW) and non-Hispanic black (NHB) during the same period were obtained from the Surveillance, Epidemiology and End Results (SEER) database. One-, three- and five-year relative survival rates were calculated using the life tables from the population of PR and SEER. In addition, a Cox proportional hazards model was employed to assess mortality hazard ratio by sex, age and tumor stage at diagnosis.

Results: A total of 76,444 subjects with incident CRC were analyzed (NHW n=59,686; NHB n=7,700; USH n=5,699; PRH n=3,359). Overall and stage-specific five-year survival rates differed by race/ethnicity. NHW had the highest overall survival rates. When comparing 5-year relative survival according to stage at diagnosis, PRH with regional CRC had the lowest five-year survival rates (59.3%; 95% CI: 53.5-65.0) when compared to NHW (69.4%; 95% CI: 67.9-70.9), NHB (61.2%; 95% CI: 56.9-65.8), and USH (65.1%; 95% CI: 59.9-70.1). Furthermore, PRH were the only racial/ethnic group in which a more marked survival advantage is was observed among females (66.0%; 95% CI: 60.6-71.2) compared to males (60.3%; 95% CI: 54.6-65.9). After adjusting by sex, age and stage at diagnosis, NHB (RR=1.27; CI 95%: 1.22-1.32) and PRH (RR=1.28; CI 95%: 1.09-1.28) had nearly the same relative risk of death from CRC, compared to NHW.

Conclusions: Our findings establish baseline survival data for CRC in PRH. The observed survival disparities among PRH warrant further investigation evaluating the interplay of molecular, behavioral and/or environmental risk factors affecting this minority population.

Citation Format: Maria Gonzalez-Pons, Mariela Torres, Marievelisse Soto-Salgado, Lorena Marcano-Bonilla, Marcia Cruz-Correa. Disparities in colorectal cancer survival among Puerto Rican Hispanics. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C30.

©2016 American Association for Cancer Research.
2016
American Association for Cancer Research.