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Factors That Contribute to Differences in Survival of Black vs White Patients With Colorectal Cancer

Published:November 13, 2017DOI:https://doi.org/10.1053/j.gastro.2017.11.005

      Background & Aims

      Previous studies reported that black vs white disparities in survival among elderly patients with colorectal cancer (CRC) were because of differences in tumor characteristics (tumor stage, grade, nodal status, and comorbidity) rather than differences in treatment. We sought to determine the contribution of differences in insurance, comorbidities, tumor characteristics, and treatment receipt to disparities in black vs white patients with CRC 18–64 years old.

      Methods

      We used data from the National Cancer Database, a hospital-based cancer registry database sponsored by the American College of Surgeons and the American Cancer Society, on non-Hispanic black (black) and non-Hispanic white (white) patients, 18–64 years old, diagnosed from 2004 through 2012 with single or first primary invasive stage I–IV CRC. Each black patient was matched, based on demographic, insurance, comorbidity, tumor, and treatment features, with 5 white patients, from partially overlapping subgroups, using propensity score and greedy matching algorithms. We used the Kaplan-Meier method to estimate 5-year survival and Cox proportional hazards models to generate hazard ratios.

      Results

      The absolute 5-year survival difference between black and white unmatched patients with CRC was 9.2% (57.3% for black patients vs 66.5% for white patients; P < .0001). The absolute difference in survival did not change after patient groups were matched for demographics, but decreased to 4.9% (47% relative decrease [4.3% of 9.2%]) when they were matched for insurance and to 2.3% when they were matched for tumor characteristics (26% relative decrease [2.4% of 9.2%]). Further matching by treatment did not reduce the difference in 5-year survival between black and white patients. In proportional hazards model, insurance and tumor characteristics matching accounted for the 54% and 27% excess risk of death in black patients, respectively.

      Conclusions

      In an analysis of data from the National Cancer Database, we found that insurance coverage differences accounted for approximately one half of the disparity in survival rate of black vs white patients with CRC, 18–64 years old; tumor characteristics accounted for a quarter of the disparity. Affordable health insurance coverage for all populations could substantially reduce differences in survival times of black vs white patients with CRC.

      Keywords

      Abbreviations used in this paper:

      CI (confidence interval), CRC (colorectal cancer), HR (hazard ratio), NCDB (National Cancer Data Base), NH (non-Hispanic)
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      References

        • Siegel R.L.
        • Miller K.D.
        • Jemal A.
        Cancer statistics, 2017.
        CA Cancer J Clin. 2017; 67: 7-30
        • Kohler B.A.
        • Sherman R.L.
        • Howlader N.
        • et al.
        Annual report to the nation on the status of cancer, 1975–2011, featuring incidence of breast cancer subtypes by race/ethnicity, poverty, and state.
        J Natl Cancer Inst. 2015; 107: djv048
        • Siegel R.L.
        • Fedewa S.A.
        • Anderson W.F.
        • et al.
        Colorectal cancer incidence patterns in the United States, 1974–2013.
        J Natl Cancer Inst. 2017; 109: djw322
        • Siegel R.L.
        • Miller K.D.
        • Jemal A.
        Cancer statistics, 2016.
        CA Cancer J Clin. 2016; 66: 7-30
        • Rahman R.
        • Schmaltz C.
        • Jackson C.S.
        • et al.
        Increased risk for colorectal cancer under age 50 in racial and ethnic minorities living in the United States.
        Cancer Med. 2015; 4: 1863-1870
        • Jessup J.M.
        • Stewart A.
        • Greene F.L.
        • et al.
        Adjuvant chemotherapy for stage III colon cancer: implications of race/ethnicity, age, and differentiation.
        JAMA. 2005; 294: 2703-2711
        • Potosky A.L.
        • Harlan L.C.
        • Kaplan R.S.
        • et al.
        Age, sex, and racial differences in the use of standard adjuvant therapy for colorectal cancer.
        J Clin Oncol. 2002; 20: 1192-1202
        • Holowatyj A.N.
        • Ruterbusch J.J.
        • Rozek L.S.
        • et al.
        Racial/ethnic disparities in survival among patients with young-onset colorectal cancer.
        J Clin Oncol. 2016; 34: 2148-2156
        • Wallace K.
        • Hill E.G.
        • Lewin D.N.
        • et al.
        Racial disparities in advanced-stage colorectal cancer survival.
        Cancer Causes Control. 2013; 24: 463-471
        • Wallace K.
        • Sterba K.R.
        • Gore E.
        • et al.
        Prognostic factors in relation to racial disparity in advanced colorectal cancer survival.
        Clin Colorectal Cancer. 2013; 12: 287-293
        • Phatak U.R.
        • Kao L.S.
        • Millas S.G.
        • et al.
        Interaction between age and race alters predicted survival in colorectal cancer.
        Ann Surg Oncol. 2013; 20: 3363-3369
        • Lai Y.
        • Wang C.
        • Civan J.M.
        • et al.
        Effects of cancer stage and treatment differences on racial disparities in survival from colon cancer: a United States population-based study.
        Gastroenterology. 2016; 150: 1135-1146
        • Soneji S.
        • Iyer S.S.
        • Armstrong K.
        • et al.
        Racial disparities in stage-specific colorectal cancer mortality: 1960-2005.
        Am J Public Health. 2010; 100: 1912-1916
        • Mayberry R.M.
        • Coates R.J.
        • Hill H.A.
        • et al.
        Determinants of black/white differences in colon cancer survival.
        J Natl Cancer Inst. 1995; 87: 1686-1693
        • Silber J.H.
        • Rosenbaum P.R.
        • Ross R.N.
        • et al.
        Racial disparities in colon cancer survival: a matched cohort study.
        Ann Intern Med. 2014; 161: 845-854
        • Marcella S.
        • Miller J.E.
        Racial differences in colorectal cancer mortality: the importance of stage and socioeconomic status.
        J Clin Epidemiol. 2001; 54: 359-366
        • Wray C.M.
        • Ziogas A.
        • Hinojosa M.W.
        • et al.
        Tumor subsite location within the colon is prognostic for survival after colon cancer diagnosis.
        Dis Colon Rectum. 2009; 52: 1359-1366
        • Le H.
        • Ziogas A.
        • Lipkin S.M.
        • et al.
        Effects of socioeconomic status and treatment disparities in colorectal cancer survival.
        Cancer Epidemiol Biomarkers Prev. 2008; 17: 1950-1962
        • Breslin T.M.
        • Morris A.M.
        • Gu N.
        • et al.
        Hospital factors and racial disparities in mortality after surgery for breast and colon cancer.
        J Clin Oncol. 2009; 27: 3945-3950
        • Tehranifar P.
        • Neugut A.I.
        • Phelan J.C.
        • et al.
        Medical advances and racial/ethnic disparities in cancer survival.
        Cancer Epidemiol Biomarkers Prev. 2009; 18: 2701-2708
        • Du X.L.
        • Fang S.
        • Vernon S.W.
        • et al.
        Racial disparities and socioeconomic status in association with survival in a large population-based cohort of elderly patients with colon cancer.
        Cancer. 2007; 110: 660-669
        • Haas J.S.
        • Brawarsky P.
        • Iyer A.
        • et al.
        Association of area sociodemographic characteristics and capacity for treatment with disparities in colorectal cancer care and mortality.
        Cancer. 2011; 117: 4267-4276
        • Simpson D.R.
        • Martínez M.E.
        • Gupta S.
        • et al.
        Racial disparity in consultation, treatment, and the impact on survival in metastatic colorectal cancer.
        J Natl Cancer Inst. 2013; 105: 1814-1820
      1. American College of Surgeons. National Cancer Data Base: 2017 update. Available at: https://www.facs.org/quality-programs/cancer/ncdb. Accessed January 26, 2017.

      2. Commission on Cancer. FORDS: Facility Oncology Registry Data Standards—Revised for 2012. Available at: https://www.facs.org/∼/media/files/quality%20programs/cancer/coc/fords/fords%202012c.ashx. Accessed November 16, 2016.

      3. Parsons LS. Reducing bias in a propensity score matched-pair sample using greedy matching techniques. Proceedings of the Twenty-sixth Annual SAS Users group international conference. SAS Institute, Cary, NC. 2001;26:214–226.

        • Rosenbaum P.R.
        • Rubin D.B.
        Reducing bias in observational studies using subclassification on the propensity score.
        J Am Stat Assoc. 1984; 79: 516-524
        • Charlson M.E.
        • Pompei P.
        • Ales K.L.
        • et al.
        A new method of classifying prognostic comorbidity in longitudinal studies: development and validation.
        J Chronic Dis. 1987; 40: 373-383
        • Halpern M.T.
        • Ward E.M.
        • Pavluck A.L.
        • et al.
        Association of insurance status and ethnicity with cancer stage at diagnosis for 12 cancer sites: a retrospective analysis.
        Lancet Oncol. 2008; 9: 222-231
        • Ward E.
        • Halpern M.
        • Schrag N.
        • et al.
        Association of insurance with cancer care utilization and outcomes.
        CA Cancer J Clin. 2008; 58: 9-31
        • Sabatino S.A.
        • White M.C.
        • Thompson T.D.
        • et al.
        Cancer screening test use—United States, 2013.
        MMWR Morb Mortal Wkly Rep. 2015; 64: 464-468
        • Ayanian J.Z.
        • Weissman J.S.
        • Schneider E.C.
        • et al.
        Unmet health needs of uninsured adults in the United States.
        JAMA. 2000; 284: 2061-2069
        • McMorrow S.
        • Long S.K.
        • Kenney G.M.
        • et al.
        Uninsurance disparities have narrowed for black and Hispanic adults under the Affordable Care Act.
        Health Aff (Millwood). 2015; 34: 1774-1778
        • Doubeni C.A.
        • Field T.S.
        • Buist D.S.
        • et al.
        Racial differences in tumor stage and survival for colorectal cancer in an insured population.
        Cancer. 2007; 109: 612-620
        • Thornton J.G.
        • Morris A.M.
        • Thornton J.D.
        • et al.
        Racial variation in colorectal polyp and tumor location.
        J Natl Med Assoc. 2007; 99: 723
        • Agrawal S.
        • Bhupinderjit A.
        • Bhutani M.S.
        • et al.
        Colorectal cancer in African Americans.
        Am J Gastroenterol. 2005; 100: 515-523
        • Baldwin L.-M.
        • Dobie S.A.
        • Billingsley K.
        • et al.
        Explaining black–white differences in receipt of recommended colon cancer treatment.
        J Natl Cancer Inst. 2005; 97: 1211-1220
        • Ayanian J.Z.
        • Zaslavsky A.M.
        • Fuchs C.S.
        • et al.
        Use of adjuvant chemotherapy and radiation therapy for colorectal cancer in a population-based cohort.
        J Clin Oncol. 2003; 21: 1293-1300
        • Demissie K.
        • Oluwole O.O.
        • Balasubramanian B.A.
        • et al.
        Racial differences in the treatment of colorectal cancer: a comparison of surgical and radiation therapy between whites and blacks.
        Ann Epidemiol. 2004; 14: 215-221
        • Hayanga A.J.
        • Waljee A.K.
        • Kaiser H.E.
        • et al.
        Racial clustering and access to colorectal surgeons, gastroenterologists, and radiation oncologists by African Americans and Asian Americans in the United States: a county-level data analysis.
        Arch Surg. 2009; 144: 532-535
        • Huang L.C.
        • Tran T.B.
        • Ma Y.
        • et al.
        What factors influence minority use of high volume hospitals for colorectal cancer care.
        Dis Colon Rectum. 2015; 58: 526
        • Phipps A.I.
        • Limburg P.J.
        • Baron J.A.
        • et al.
        Association between molecular subtypes of colorectal cancer and patient survival.
        Gastroenterology. 2015; 148: 77-87.e2
        • Carethers J.M.
        • Murali B.
        • Yang B.
        • et al.
        Influence of race on microsatellite instability and CD8+ T cell infiltration in colon cancer.
        PLoS One. 2014; 9: e100461
        • Ball J.K.
        • Elixhauser A.
        Treatment differences between blacks and whites with colorectal cancer.
        Med Care. 1996; 34: 970-984
        • Sanoff H.K.
        • Sargent D.J.
        • Green E.M.
        • et al.
        Racial differences in advanced colorectal cancer outcomes and pharmacogenetics: a subgroup analysis of a large randomized clinical trial.
        J Clin Oncol. 2009; 27: 4109-4115
        • Yoon H.H.
        • Shi Q.
        • Alberts S.R.
        • et al.
        Racial differences in BRAF/KRAS mutation rates and survival in stage III colon cancer patients.
        J Natl Cancer Inst. 2015; 107: djv186
        • Mettlin C.J.
        • Menck H.R.
        • Winchester D.P.
        • et al.
        A comparison of breast, colorectal, lung, and prostate cancers reported to the National Cancer Data Base and the Surveillance, Epidemiology, and End Results Program.
        Cancer. 1997; 79: 2052-2061
      4. Ries L, Melbert D, Krapcho M, et al. SEER cancer statistics review, 1975–2014. Available at: https://seer.cancer.gov/csr/1975_2014/. Bethesda, MD; National Cancer Institute.

      5. Surveillance Epidemiology, and End Results (SEER) Program Research Data (1973-2014), National Cancer Institute, DCCPS, Surveillance Research Program, released April 2017, based on the November 2016 submission. Available at: www.seer.cancer.gov. Accessed August 2, 2017.

      Reference

      1. Parsons LS. Reducing bias in a propensity score matched-pair sample using greedy matching techniques. Proceedings of the Twenty-sixth Annual SAS Users group international conference. SAS Institute, Cary, NC. 2001;26:214–226.