The impact of race on outcomes of patients with early stage uterine endometrioid carcinoma

Racial disparities in endometrial cancer: Where are we after 26 years?

INTRODUCTION

Endometrial cancer is the most commonly diagnosed female genital tract malignancy in the United States of America. Racial disparities surrounding this particular disease have been extensively investigated for over 26-years. We sought to determine if research in this area has led to any significant improvements in this disparity.

METHODS

We performed a rapid systematic review of English language publications on racial disparities in endometrial cancer among African American (AAW) and white American women (WAW), from 1997 to 2023. We looked at trends in incidence and survival; impact of known poor prognostic factors (stage at diagnosis, histological subtypes, grade); co-morbidities; differences in treatment (surgery, radiation and chemotherapy); socioeconomic factors; differences in biological and genetic markers; and policies/declarations.

RESULTS

During the period under review (1997-2023), there was a notable increase in both disease incidence (39%) and mortality (26%) rates for AAW, in comparison to WAW among whom the incidence rates increased by 2% and mortality rates rose, but 9% less than for AAW. It should be noted that the current incidence rate of 29.4% in AAW represent a reversal of what is was 26-years ago, when the incidence rate was 17.8%. In comparison to WAW, AAW had a higher prevalence of poor prognostic variables, more co-morbidities, lower income levels, less insurance coverage, and were more frequently under treated with surgery, chemotherapy and radiation. To date no actionable molecular/genetic markers have been identified. We were unable to locate any published recommendations or active programs of implementation strategies/policies designed to effectively mitigate the documented racial disparity.

CONCLUSION

Racial disparities in disease incidence and mortality in endometrial cancer rates between WAW and AAW have widened during a 26-year period of robust research, suggesting that current research alone is not enough to eliminate this disparity. Based on this rapid systematic review we have identified and analyzed the impact of causation variables on this disparity. Additionally, we have made strong and pertinent recommendations for the benefit of mitigating this escalating racial disparity.

Landmark Series on Disparities: Uterine Cancer and Strategies for Mitigation

Longstanding racial disparities exist in uterine cancer. There is a growing body of literature documenting differences in the prevalence, diagnosis, treatment, and tumor characteristics of uterine cancer in Black women compared with White women that significantly contribute to the outcome disparity seen between the groups. This article seeks to provide an overview of racial disparities present in uterine cancer, with attention on Black women in the USA, as well as offer a review on the multifactorial etiology of the disparities described.

Racial and Ethnic Differences in Hysterectomy-Corrected Uterine Corpus Cancer Mortality by Stage and Histologic Subtype

Importance

Uterine cancer incidence has been increasing, particularly rates of aggressive, nonendometrioid subtypes, which are disproportionately higher among non-Hispanic Black women. The association of subtype-specific trends with uterine cancer mortality and with the role of tumor subtype and stage at diagnosis with racial disparities in uterine cancer deaths at the population-based level are not known.

Objective

To estimate histologic subtype- and stage-specific uterine cancer mortality rates by race and ethnicity, corrected for hysterectomy.

Design, Setting, and Participants

This cohort study used the US Surveillance, Epidemiology, and End Results-18 Incidence-Based Mortality database, representing approximately 26% of the US population and including deaths that occurred from 2000 to 2017. Hysterectomy correction was based on hysterectomy prevalence data from the Behavioral Risk Factor Surveillance System. Uncorrected and corrected rates associated with uterine corpus cancer cases diagnosed between 2000 and 2017 and uterine corpus cancer deaths occurring between 2010 and 2017 were age-adjusted to the 2000 US standard population and are expressed per 100 000 person-years, and annual percent changes in rates were calculated using log-linear regression. Data analysis was performed from March 10 to May 20, 2021.

Exposures

Tumor histologic subtype, cancer stage at diagnosis, and race and ethnicity.

Results

Among 208 587 women diagnosed with uterine cancer during 2000-2017 (15 983 [7.7%] were Asian; 20 302 [9.7%] Black; 23 096 [11.1%] Hispanic; and 149 206 [71.5%] White individuals), there were 16 797 uterine cancer deaths between 2010 and 2017, corresponding to a hysterectomy-corrected mortality rate of 15.7 per 100 000 person-years. Hysterectomy-corrected rates were highest among Black women, overall, by histologic subtype and stage at diagnosis. Among all women, uterine corpus cancer mortality rates increased significantly by 1.8% (95% CI, 1.5%-2.9%) per year from 2010 to 2017, as did rates of nonendometrioid carcinomas (2.7%; 95% CI, 1.8%-3.6%), with increases occurring in Asian (3.4%; 95% CI, 0.3%-6.6%), Black (3.5%; 95% CI, 2.2%-4.9%), Hispanic (6.7%; 95% CI, 1.9%-11.8%), and White women (1.5%; 95% CI, 0.6%-2.4%). In contrast, endometrioid carcinoma mortality rates remained stable.

Conclusions and Relevance

The findings of this cohort study suggest a significant increase of nonendometrioid uterine carcinoma mortality rates, aligning with recent incidence trends. The factors associated with these trends are not well understood and require more investigation of possible mechanisms. Despite stable incidence rates, endometrioid cancer mortality rates have not decreased over the past decade at the population level, suggesting limited progress in treatment for these cancers. The substantial disparities in uterine corpus cancer mortality rates among non-Hispanic Black women cannot be fully explained by subtype distribution and stage at diagnosis.

Health Disparities in Uterine Cancer: Report From the Uterine Cancer Evidence Review Conference

The Centers for Disease Control and Prevention recognized the need for educational materials for clinicians on the prevention and early diagnosis of gynecologic cancers. The American College of Obstetricians and Gynecologists convened a panel of experts in evidence review from the Society for Academic Specialists in General Obstetrics and Gynecology and content experts from the Society of Gynecologic Oncology to review relevant literature, best practices, and existing practice guidelines for the development of evidence-based educational materials for women's health care clinicians about uterine cancer. This article is the evidence summary of the literature review of health disparities and inequities related to uterine cancer. Substantive knowledge gaps are noted and summarized to provide guidance for future research.

More than treatment refusal: a National Cancer Database analysis of adjuvant treatment refusal and racial survival disparities among women with endometrial cancer

BACKGROUND

Disparities in adjuvant treatment between Black and White women with endometrial cancer exist and contribute to worse outcomes among Black women. However, factors leading to disparate treatment receipt are understudied.

OBJECTIVE

We examined whether patient refusal of adjuvant treatment (chemotherapy or radiation) differed between Black and White women and whether treatment refusal mediated racial disparities in survival among women with endometrial cancer.

STUDY DESIGN

We used the National Cancer Database, a hospital-based cancer registry, to identify non-Hispanic Black and non-Hispanic White women diagnosed with endometrial cancer from 2004 to 2016 who either received or refused recommended radiation or chemotherapy. We used logistic regression to estimate multivariable-adjusted odds ratios and 95% confidence intervals for associations between race and treatment refusal. We also examined predictors of treatment refusal in race-specific models. Accelerated failure time models were used to estimate absolute differences in overall survival by race. We used causal mediation analysis to estimate the proportion of racial differences in overall survival attributable to racial differences in adjuvant treatment refusal. We considered the overall study population and strata defined by histology, and adjusted for sociodemographic, tumor, and facility characteristics.

RESULTS

Our analysis included 75,447 endometrial cancer patients recommended to receive radiation and 60,187 endometrial cancer patients recommended to receive chemotherapy, among which 6.4% and 11.4% refused treatment, respectively. Among Black women recommended for radiation or chemotherapy, 6.4% and 9.6% refused, respectively. Among White women recommended for radiation or chemotherapy, 6.4% and 11.8% refused, respectively. After adjusting for sociodemographic variables, facility characteristics, and tumor characteristics, Black women were more likely to refuse chemotherapy than White women (adjusted odds ratio, 1.26; 95% confidence interval, 1.15-1.37), but no difference in radiation refusal was observed (adjusted odds ratio, 1.00; 95% confidence interval, 0.91-1.11). Some predictors of radiation refusal varied by race, namely income, education, histology, stage, and chemotherapy receipt (P interactions<.05), whereas predictors of chemotherapy refusal were generally similar between Black and White women. Among women recommended for radiation, Black women survived an average of 4.3 years shorter than White women, which did not seem attributable to differences in radiation refusal. Among women recommended for chemotherapy, Black women survived an average of 3.2 years shorter than White women of which 1.9 months (4.9%) could potentially be attributed to differences in chemotherapy refusal.

CONCLUSION

We observed differences in chemotherapy refusal by race, and those differences may be responsible for up to about 2 months of the overall 3.2-year survival disparity between White and Black women. Radiation refusal did not explain any of the 4.3-year disparity among women recommended for radiation. Treatment refusal accounts for, at most, a small fraction of the total racial disparity in endometrial cancer survival. Although a better understanding of the reasons for patient treatment refusal and subsequent intervention may help improve outcomes for some women, other causes of disparate outcomes, particularly those reflecting the social determinants of health, must be investigated.

Racial disparities in survival among women with endometrial cancer in an equal access system

OBJECTIVE

The mortality rate for Black women with endometrial cancer (EC) is double that of White women, although the incidence rate is lower among Black women. Unequal access to care may contribute to this racial disparity. This study aimed to assess whether survival varied between non-Hispanic Black (NHB) and non-Hispanic White (NHW) women with EC in the Military Health System (MHS) which provides equal access care to its beneficiaries despite racial/ethnic background.

METHODS

The study was conducted using data from the U.S. Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR). Study subjects included NHB and NHW women with histologically confirmed and surgically managed EC diagnosed between 1988 and 2013. The study outcome was all-cause death. Overall survival between NHB and NHW women was compared using multivariable Cox modeling.

RESULTS

The study included 144 NHB and 1439 NHW women with EC. Kaplan-Meier curves showed NHB women had worse survival than NHW women (log-rank P < 0.0001). The disparity in survival between NHB and NHW women persisted after adjusting for age, diagnosis period, tumor stage, tumor histology/grade, and adjuvant treatment (HR = 1.64, 95% CI = 1.19 to 2.27). Multivariable analyses stratified by tumor features or treatment showed that the racial disparity was confined to women with low-risk features (stage I/II disease or low-grade EC) or no adjuvant treatment.

CONCLUSION

There were racial differences in overall survival between NHB and NHW women with EC in the MHS equal access healthcare system, suggesting that factors other than access to care may be related to this racial disparity.

The impact of race, comorbid conditions and obesity on survival endpoints in women with high grade endometrial carcinoma

OBJECTIVE

To estimate overall survival, disease-specific survival, and progression-free survival among high grade endometrial carcinoma cases and to determine factors impacting survival for non-Hispanic white and non-Hispanic black women.

METHODS

We identified high grade endometrial carcinoma cases among non-Hispanic white and non-Hispanic black women from ongoing institutional studies, and determined eligibility through medical record and pathologic review. We estimated effects of demographic and clinical variables on survival outcomes using Kaplan Meier methods and Cox proportional hazards modelling.

RESULTS

Non-Hispanic Black women with BMI <25.0 had poorest overall survival compared to non-Hispanic white women with BMI <25.0 (HR 3.03; 95% CI [1.35, 6.81]), followed by non-Hispanic black women with BMI 25.0+ (HR 2.43; 95% CI [1.28, 4.60]). A similar pattern emerged for disease-specific survival. Non-Hispanic black women also had poorer progression-free survival than non-Hispanic white women (HR 1.40; 95% CI [1.01, 1.93]). Other significant factors impacting survival outcomes included receipt of National Cancer Center Network (NCCN) guideline-concordant treatment (GCT), earlier stage at diagnosis, and fewer comorbid conditions.

CONCLUSIONS

BMI and race interact and modify the association with high grade endometrial carcinoma survival. Other potentially modifiable factors, such as reducing comorbidities and increasing access to GCT will potentially improve survival after diagnosis of high grade endometrial carcinomas. A better understanding of the molecular drivers of these high grade carcinomas may lead to targeted therapies that reduce morbidity and mortality associated with these aggressive tumors.

Black and Hispanic women are less likely than white women to receive guideline-concordant endometrial cancer treatment

BACKGROUND

Differences in receipt of guideline-concordant treatment might underlie well-established racial disparities in endometrial cancer mortality.

OBJECTIVE

Using the National Cancer Database, we assessed the hypothesis that among women with endometrioid endometrial cancer, racial/ethnic minority women would have lower odds of receiving guideline-concordant treatment than white women. In addition, we hypothesized that lack of guideline-concordant treatment was linked with worse survival.

STUDY DESIGN

We defined receipt of guideline-concordant treatment using the National Comprehensive Cancer Network guidelines. Multivariable logistic regression models were used to compute odds ratios and 95% confidence intervals for associations between race and guideline-concordant treatment. We used multivariable Cox proportional hazards regression models to estimate hazards ratios and 95% confidence intervals for relationships between guideline-concordant treatment and overall survival in the overall study population and stratified by race/ethnicity.

RESULTS

This analysis was restricted to the 89,319 women diagnosed with an invasive, endometrioid endometrial cancer between 2004 and 2014. Overall, 74.7% of the cohort received guideline-concordant treatment (n = 66,699). Analyses stratified by race showed that 75.3% of non-Hispanic white (n = 57,442), 70.1% of non-Hispanic black (n = 4334), 71.0% of Hispanic (n = 3263), and 72.5% of Asian/Pacific Islander patients (n = 1660) received treatment in concordance with guidelines. In multivariable-adjusted models, non-Hispanic black (odds ratio, 0.92, 95% confidence interval, 0.86-0.98) and Hispanic women (odds ratio, 0.90, 95% confidence internal, 0.83-0.97) had lower odds of receiving guideline-concordant treatment compared with non-Hispanic white women, while Asian/Pacific Islander women had a higher odds of receiving guideline-concordant treatment (odds ratio, 1.11, 95% confidence interval, 1.00-1.23). Lack of guideline-concordant treatment was associated with lower overall survival in the overall study population (hazard ratio, 1.12, 95% confidence interval, 1.08-1.15) but was not significantly associated with overall survival among non-Hispanic black (hazard ratio, 1.09, 95% confidence interval, 0.98-1.21), Hispanic (hazard ratio, 0.92, 95% confidence interval=0.78-1.09), or Asian/Pacific Islander (hazard ratio, 0.90, 95% confidence interval, 0.70-1.16) women.

CONCLUSION

Non-Hispanic black and Hispanic women were less likely than non-Hispanic white women to receive guideline-concordant treatment, while Asian/Pacific Islander women more commonly received treatment in line with guidelines. Furthermore, in the overall study population, overall survival was worse among those not receiving guideline-concordant treatment, although low power may have had an impact on the race-stratified models. Future studies should evaluate reasons underlying disparate endometrial cancer treatment.

Receipt of adjuvant endometrial cancer treatment according to race: an NRG Oncology/Gynecologic Oncology Group 210 Study

BACKGROUND

Black women with endometrial cancer are more likely to die of their disease compared with white women with endometrial cancer. These survival disparities persist even when disproportionately worse tumor characteristics among black women are accounted. Receipt of less complete adjuvant treatment among black patients with endometrial cancer could contribute to this disparity.

OBJECTIVE

We assessed the hypothesis that black women with endometrial cancer are less likely than their white counterparts to receive adjuvant treatment within subgroups defined by tumor characteristics in the NRG Oncology/Gynecology Oncology Group 210 Study.

STUDY DESIGN

Our analysis included 615 black and 4283 white women with endometrial cancer who underwent hysterectomy. Women completed a questionnaire that assessed race and endometrial cancer risk factors. Tumor characteristics were available from pathology reports and central review. We categorized women as low-, intermediate-, or high-risk based on the European Society for Medical Oncology definition. Adjuvant treatment was documented during postoperative visits and was categorized as no adjuvant treatment (54.3%), radiotherapy only (16.5%), chemotherapy only (15.2%), and radiotherapy plus chemotherapy (14.0%). We used polytomous logistic regression to estimate odds ratios and 95% confidence intervals for multivariable-adjusted associations between race and adjuvant treatment in the overall study population and stratified by tumor subtype, stage, or European Society for Medical Oncology risk category.

RESULTS

Overall, black women were more likely to have received chemotherapy only (odds ratio, 1.40; 95% confidence interval, 1.04-1.86) or radiotherapy plus chemotherapy (odds ratio, 2.01; 95% confidence interval, 1.54-2.62) compared with white women in multivariable-adjusted models. No racial difference in the receipt of radiotherapy only was observed. In tumor subtype-stratified models, black women had higher odds of receiving radiotherapy plus chemotherapy than white women when diagnosed with low-grade endometrioid (odds ratio, 2.04; 95% confidence interval, 1.06-3.93) or serous tumors (odds ratio, 1.81; 95% confidence interval, 1.07-3.08). Race was not associated with adjuvant treatment among women who had been diagnosed with other tumor subtypes. In stage-stratified models, we observed no racial differences in the receipt of adjuvant treatment. In models that were stratified by European Society for Medical Oncology risk group, black women with high-risk cancer were more likely to receive radiotherapy plus chemotherapy compared with white women (odds ratio, 1.41; 95% confidence interval, 1.03-1.94).

CONCLUSION

Contrary to our hypothesis, we observed higher odds of specific adjuvant treatment regimens among black women as compared with white women within specific subgroups of endometrial cancer characteristics.

Endometrial cancer disparities: a race-conscious critique of the literature

Racial disparities in endometrial cancer are stark and have increased over the past decade. While the disparities are well documented, intervention work to address the mortality gap is nonexistent. This review critiques how race has been conceptualized to explain the causes of endometrial cancer disparities, assesses gaps in knowledge production, and proposes new research priorities. Using public health critical race praxis, a research approach for examining racial disparities and knowledge production processes, we reviewed the endometrial cancer disparities literature from 1995 through 2016. Using systematic search methods, 133 unique records were identified and 48 studies critiqued. We found that a narrow definition of race as a purely biological construct is common throughout the literature. This appears to result in an underemphasis on the role of modifiable, nonbiological contributors to racial disparities and a lack of follow-up work to address these contributors. Key knowledge gaps identified were the role of health care systems in early diagnosis, a lack of intervention studies to address persistent treatment inequity by race, and the near absence of qualitative work to understand the perspectives of Black women diagnosed with endometrial cancer. We conclude with an iterative demonstration of the public health critical race praxis and suggest new routes of inquiry to broaden the scope of research priorities to understand and improve the outcomes of Black women with endometrial cancer.

Impact of age at diagnosis on racial disparities in endometrial cancer patients

INTRODUCTION

Although black patients with endometrial cancer (EC) have worse survival compared with white patients, the interaction between age/race has not been examined. The primary objective was to evaluate the impact of age at diagnosis on racial disparities in disease presentation and outcome in EC.

METHODS

We evaluated women diagnosed with EC between 1991 and 2010 from the Surveillance, Epidemiology, and End Results. Mutation status for TP53 or PTEN, or with the aggressive integrative, transcript-based, or somatic copy number alteration-based molecular subtype were acquired from the Cancer Genome Atlas. Logistic regression model was used to estimate the interaction between age and race on histology. Cox regression model was used to estimate the interaction between age and race on survival.

RESULTS

78,184 white and 8518 black patients with EC were analyzed. Median age at diagnosis was 3-years younger for black vs. white patients with serous cancer and carcinosarcoma (P<0.0001). The increased presentation of non-endometrioid histology with age was larger in black vs. white patients (P<0.0001). The racial disparity in survival and cancer-related mortality was more prevalent in black vs. white patients, and in younger vs. older patients (P<0.0001). Mutations in TP53, PTEN and the three aggressive molecular subtypes each varied by race, age and histology.

CONCLUSIONS

Aggressive histology and molecular features were more common in black patients and older age, with greater impact of age on poor tumor characteristics in black vs. white patients. Racial disparities in outcome were larger in younger patients. Intervention at early ages may mitigate racial disparities in EC.

Endometrial carcinoma recurrence according to race and ethnicity: An NRG Oncology/Gynecologic Oncology Group 210 Study

Non-Hispanic black (NHB) women are more likely to experience an endometrial carcinoma (EC) recurrence compared to non-Hispanic white (NHW) women. The extent to which tumor characteristics, socioeconomic status (SES) and treatment contribute to this observation is not well defined. In the NRG Oncology/Gynecology Oncology Group (GOG) 210 Study we evaluated associations between race/ethnicity and EC recurrence according to tumor characteristics with adjustment for potential confounders. Our analysis included 3,199 NHW, 532 NHB and 232 Hispanic women with EC. Recurrence was documented during follow-up. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between race/ethnicity and EC recurrence in models stratified by histologic subtype (low-grade endometrioid, high-grade endometrioid, serous, mixed cell, carcinosarcoma, clear cell) or stage (I, II, III) and adjusted for age, SES, body mass index, smoking status and treatment. In histologic subtype-stratified models, higher EC recurrence was noted in NHB women with low-grade endometrioid (HR = 1.94, 95% CI = 1.21-3.10) or carcinosarcomas (HR = 1.66, 95% CI = 0.99-2.79) compared to NHWs. In stage-stratified models, higher EC recurrence was noted among NHB women with stage I (HR = 1.48, 95% CI = 1.06-2.05) and Hispanic women with stage III disease (HR = 1.81, 95% CI = 1.11-2.95). Our observations of higher EC recurrence risk among NHB and Hispanic women, as compared to NHW women, were not explained by tumor characteristics, SES, treatment or other confounders. Other factors, such as racial differences in tumor biology or other patient factors, should be explored as contributors to racial disparities in EC recurrence.

Racial disparities in endometrial cancer mortality-to-incidence ratios among Blacks and Whites in South Carolina

PURPOSE

Endometrial cancer (EC) exhibits striking racial disparities with higher mortality in Blacks compared to Whites. The mortality-to-incidence ratio (MIR) provides a population-based measure of survival which accounts for incidence. The objective of this study was to map EC MIRs by race for eight health regions within South Carolina (SC) and chart EC incidence by race and grade across the four cancer stages.

METHODS

Cancer incidence and mortality data were obtained from the SC Community Access Network (SCAN), the online data query system provided by the SC Department of Health and Environmental Control (DHEC). The underlying data for SCAN were generated from the SC Central Cancer Registry and SC DHEC Vital Records and used to construct MIRs. ArcGIS 10.1 was used to map EC MIRs by race for eight health regions within SC. Four categories of MIR were derived using the national MIR for EC among Whites as the reference category.

RESULTS

Blacks had higher levels of poorly differentiated tumors across all stages and higher incidence and mortality rates. In all eight health regions, Blacks were in the highest MIR category. By contrast, the MIRs for Whites were more evenly represented over the four categories.

CONCLUSIONS

The MIR proved useful for identifying disparities in EC incidence and mortality among Black and White women in SC. Cancer surveillance programs may use the MIR to monitor disparities across racial/ethnic groups and geographic regions going forward. MIRs have the potential to serve as an indicator of the long-term success of cancer surveillance programs.

Genetics of endometrial cancer

Women who report a history of endometrial cancer in a first-degree relative are at increased risk of endometrial cancer, with a hazard ratio of 1.5 to 2.0. Only a minority of patients with familial endometrial cancer have a recognized cancer syndrome. Lynch syndrome is the most common genetic syndrome associated with endometrial cancer and a marked increased risk of colon cancer. Cowden syndrome is a rare condition resulting from a mutation in the tumor suppressor gene phosphatase and tensin homolog. The risk for endometrial cancer is about five times higher in women with Cowden syndrome than in the general population. Recently, a novel germline mutation in the POLD1 gene that encodes the catalytic subunit of DNA polymerase δ was described in several families with multiple cases of endometrial cancer. This mutation is also associated with colorectal cancer. The association between BRCA1 mutations and endometrial cancer has been investigated in several studies; it appears that the risk of endometrial cancer is restricted to women with a history of tamoxifen exposure. In recent years, research has focused on genetic polymorphisms that are associated with endometrial cancer risk. Although many polymorphisms have been identified, their clinical significance is unclear and they have not been adapted for clinical practice.