In a recent study, histologic subtype accounted for 54.1% of the excess relative risk for Black patients compared to White patients with uterine cancer.
Racial survival disparity in patients with uterine cancer is predominantly caused by histologic subtype, according to a recent study published in JAMA Network Open.
Uterine cancer cases and mortalities are increasing in the United States, with 66,570 new cases and 12,940 deaths observed. Historically, Black patients have experienced increased risk of aggressive disease, recurrence, and death compared to White patients.
Differences in cancer diagnoses and survival between racial groups have been seen even among patients with equal access to care for uterine cancer. Racial disparities have been attributed to social constructs and biological associations of inherited ancestry.
To determine factors associated with racial disparities in survival among patients with uterine cancer, investigators conducted a cohort study using data from the National Cancer Database (NCDB). Patients diagnosed with uterine cancer from January 1, 2004, to December 31, 2017, with follow-up through December 2020 were included.
A diagnosis of stage 1 to stage 4 uterine cancer was required for participation. Participants were categorized using 2 self-reported NCDB coded variables, race and Hispanic ethnicity.
There were 274,838 patients included in the analysis, 242,608 if which were White and 32,230 of which were Black. Patients were aged a mean 63.5 years at diagnosis, with 17,415 Black and 136,391 White patients diagnosed when aged under 65 years, while 14,815 Black and 106,207 White patients were diagnosed when aged 65 years and older.
Comorbidities were seen in 26.2% of patients, a diagnosis of nonendometrioid subtype in 24.5%, and stage 3 to 4 disease beyond the uterus in 21.5%.
A comorbidity score of 1 or more was seen in 32.6% of Black patients vs 25.3% of White patients, low income in 44.1% vs 14%, no insurance or Medicaid insurance in 16.2% vs 6.7%, nonendometrioid histologic characteristics in 46.1% vs 21.6%, advanced disease stage in 34.1% vs 19.8%, no surgery in 12.3% vs 5.6%, and chemotherapy in 33.8% vs 19.4%.
Death occurred in 26.7% of patients, with a significantly worse survival rate in Black patients than White patients. The 5-year survival rate was 58.6% for Black patients and 78.5% for White patients, and Black patients had a 2.11 times greater unadjusted risk of death compared to White patients.
The hazard ratio (HR) before adjustment was 2.56 in patients aged under 65 years before Medicare eligibility and 1.84 after Medicare eligibility, indicating a significant magnitude of survival disparity. Worse survival among Black patients was attributed to histologic subtype, disease stage, and first-line treatment status independently.
In the adjusted model, the HR for Black patientsvs White patients was 2.03. The HR for death was 1.29 after adjustment in patients aged under 65 years and 1.14 in patients aged 65 years and older. Insurance status accounted for 11.5% of the survival disparity for patients aged under 65 years but was not associated with a difference in patients aged 65 years and older.
Of the excess relative risk (ERR) for Black patients compared to White patients, 82.3% was attributed to neighborhood income, comorbidity score, histologic subtype, insurance status, disease stage, and treatment.
Neighborhood income accounted for 8.2% of the ERR, comorbidity score 1.9%, histologic subtype 54.1%, insurance status 6.3%, disease stage 8.3%, and treatment 2.5%, while 17.7% was unexplained. The largest attribution was seen in histologic subtype, making it the dominant factor associated with racial disparity among patients with uterine cancer.
Kucera CW, Tian C, Tarney CM, et al. Factors associated with survival disparities between non-hispanic black and white patients with uterine cancer. JAMA Netw Open. 2023;6(4):e238437. doi:10.1001/jamanetworkopen.2023.8437