Assessing Racial Disparities in Guideline-Concordant Care and Clinical Outcomes after Surgical Resection of Nonmetastatic Colon Cancer at a Comprehensive Cancer Center

Abstract

In this study, we examined racial disparities in guideline-concordant care (GCC) and clinical outcomes of patients with colon cancer treated at a single comprehensive cancer center. We analyzed data from self-reported Hispanic, non-Hispanic Black (NHB), and non-Hispanic White (NHW) patients who underwent curative colectomy for stage I to III colon cancer between 2006 and 2021 at Memorial Sloan Kettering Cancer Center. GCC was defined as retrieval of ≥12 lymph nodes and appropriate receipt of adjuvant chemotherapy. Recurrence and overall survival from the time of surgery were compared using the Kaplan-Meier method and the log-rank test. Multivariable analyses were performed using Cox regression. The study included 2,209 patients, with 1,911 NHW, 153 NHB, and 145 Hispanic patients. NHW patients were older, whereas NHB patients had higher percentages of Medicaid coverage, obesity, and lower socioeconomic status. NHB patients more often presented with stage III disease and underwent open surgery. Receipt of GCC was not different by race. NHB patients had the highest 5-year recurrence rate compared with NHW and Hispanic patients (27% vs. 15.7% vs. 15.1%; P = 0.03). NHB race (HR = 1.43; P = 0.07) and low body mass index (HR = 1.98; P = 0.05) were associated with an increased risk of recurrence with marginal significance. NHB race was associated with an increased risk of recurrence in stage I disease (HR = 3.52; P = 0.03). NHB patients had shorter recurrence-free survival, despite standardized quality of care. NHB race was independently associated with an increased risk of recurrence in stage I disease.

Significance: This study compares receipt of GCC, disease recurrence, and survival among White, Black, and Hispanic patients with nonmetastatic colon cancer treated at a single comprehensive cancer center with standardized quality of care and comparable access to health care. Black patients had higher rates of recurrence in this study.

Figure 1

Cohort overview and description of clinical features. A, CONSORT diagram of patients included in the study. RT, radiotherapy. B, Baseline comorbidities by racial and ethnic groups. C, Description of the type of operative approach by racial group and procedure year. Left top plot, percentage of racial groups included in the study by procedure year; left bottom plot, ratio of the approach by procedure year. D, Differences in receipt of GCC by racial groups. Results are shown for NHW (left), NHB (middle), and Hispanic (right) patients.

Figure 2

Comparison of clinical outcomes after surgical resection for NHW, NHB, and Hispanic patients. A, Kaplan–Meier (product-limit) estimator shows cumulative recurrence rates. The log-rank test was used to compare recurrence rates of NHW, NHB, and Hispanic patients. B, Forest plot shows results from multivariate Cox regression analysis for recurrence. C, Kaplan–Meier (product-limit) estimators show stage-specific cumulative recurrence rates.