Racial disparities in colorectal cancer time-to-treatment and survival time in relation to diagnosing hospital cancer-related diagnostic and treatment capabilities

Racial disparities in colorectal cancer clinicopathological and molecular tumor characteristics: a systematic review

PURPOSE

African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced stage at diagnosis. Recent evidence indicates that differences in tumor characteristics may also underlie disparities in mortality. To highlight recent findings and areas for investigation, we completed the first systematic review of racial disparities in CRC tumor prognostic markers, including clinicopathological markers, microsatellite instability (MSI), oncogene mutations, and novel markers, including cancer stem cells and immune markers.

METHODS

Relevant studies were identified via PubMed, limited to original research published within the last 10 years. Ninety-six articles were identified that compared the prevalence of mortality-related CRC tumor characteristics in African Americans (or other African ancestry populations) to White cases.

RESULTS

Tumors from African ancestry cases are approximately 10% more likely to contain mutations in KRAS, which confer elevated mortality and resistance to epidermal growth factor receptor inhibition. Conversely, African Americans have approximately 50% lower odds for BRAF-mutant tumors, which occur less frequently but have similar effects on mortality and therapeutic resistance. There is less consistent evidence supporting disparities in mutations for other oncogenes, including PIK3CA, TP53, APC, NRAS, HER2, and PTEN, although higher rates of PIK3CA mutations and lower prevalence of MSI status for African ancestry cases are supported by recent evidence. Although emerging evidence suggests that immune markers reflecting anti-tumor immunity in the tumor microenvironment may be lower for African American cases, there is insufficient evidence to evaluate disparities in other novel markers, cancer stem cells, microRNAs, and the consensus molecular subtypes.

CONCLUSION

Higher rates of KRAS-mutant tumors in in African Americans may contribute to disparities in CRC mortality. Additional work is required to understand whether emerging markers, including immune cells, underlie the elevated CRC mortality observed for African Americans.

Quality of Care at the End of Life: Applying the Intersection of Race and Gender

BACKGROUND AND OBJECTIVES

Research on racial and gender disparities in end-of-life care quality has burgeoned over the past few decades, but few studies have incorporated the theory of intersectionality, which posits that membership in 2 or more vulnerable groups may result in increased hardships across the life span. As such, this study aimed to examine the intersectional effect of race and gender on the quality of care received at the end of life among older adults.

RESEARCH DESIGN AND METHODS

Data were derived from the combined Round 3 to Round 10 of the National Health and Aging Trends Study. For multivariate analyses, 2 logistic regression models were run; Model 1 included the main effects of race and gender and Model 2 included an interaction term for race and gender.

RESULTS

Results revealed that White men were the most likely to have excellent or good care at the end of life, followed by White women, Black men, and Black women, who were the least likely to have excellent or good care at the end of life.

DISCUSSION AND IMPLICATIONS

These results point to a significant disadvantage for Black women, who had worse end-of-life care quality than their gender and racial peers. Practice interventions may include cultural humility training and a cultural match between patients and providers. From a policy standpoint, a universal health insurance plan would reduce the gap in end-of-life service access and quality for Black women, who are less likely to have supplemental health care coverage.

Black-White disparities in colorectal cancer outcomes: a simulation study of screening benefit

The US Black population has higher colorectal cancer (CRC) incidence rates and worse CRC survival than the US White population, as well as historically lower rates of CRC screening. The Surveillance, Epidemiology, and End Results incidence rate data in people diagnosed between the ages of 20 and 45 years, before routine CRC screening is recommended, were analyzed to estimate temporal changes in CRC risk in Black and White populations. There was a rapid rise in rectal and distal colon cancer incidence in the White population but not the Black population, and little change in proximal colon cancer incidence for both groups. In 2014-2018, CRC incidence per 100 000 was 17.5 (95% confidence interval [CI] = 15.3 to 19.9) among Black individuals aged 40-44 years and 16.6 (95% CI = 15.6 to 17.6) among White individuals aged 40-44 years; 42.3% of CRCs diagnosed in Black patients were proximal colon cancer, and 41.1% of CRCs diagnosed in White patients were rectal cancer. Analyses used a race-specific microsimulation model to project screening benefits, based on life-years gained and lifetime reduction in CRC incidence, assuming these Black-White differences in CRC risk and location. The projected benefits of screening (via either colonoscopy or fecal immunochemical testing) were greater in the Black population, suggesting that observed Black-White differences in CRC incidence are not driven by differences in risk. Projected screening benefits were sensitive to survival assumptions made for Black populations. Building racial disparities in survival into the model reduced projected screening benefits, which can bias policy decisions.

Differential Effects of Race, Socioeconomic Status, and Insurance on Disease-Specific Survival in Rectal Cancer

BACKGROUND

National Comprehensive Cancer Network guideline adherence improves cancer outcomes. In rectal cancer, guideline adherence is distributed differently by race/ethnicity, socioeconomic status, and insurance.

OBJECTIVE

This study aimed to determine the independent effects of race/ethnicity, socioeconomic status, and insurance status on rectal cancer survival after accounting for differences in guideline adherence.

DESIGN

This was a retrospective study.

SETTINGS

The study was conducted using the California Cancer Registry.

PATIENTS

This study included patients aged 18 to 79 years diagnosed with rectal adenocarcinoma between January 1, 2004, and December 31, 2017, with follow-up through November 30, 2018. Investigators determined whether patients received guideline-adherent care.

MAIN OUTCOME MEASURES

ORs and 95% CIs were used for logistic regression to analyze patients receiving guideline-adherent care. Disease-specific survival analysis was calculated using Cox regression models.

RESULTS

A total of 30,118 patients were examined. Factors associated with higher odds of guideline adherence included Asian and Hispanic race/ethnicity, managed care insurance, and high socioeconomic status. Asians (HR, 0.80; 95% CI, 0.72-0.88; p < 0.001) and Hispanics (HR, 0.91; 95% CI, 0.83-0.99; p = 0.0279) had better disease-specific survival in the nonadherent group. Race/ethnicity were not factors associated with disease-specific survival in the guideline adherent group. Medicaid disease-specific survival was worse in both the nonadherent group (HR, 1.56; 95% CI, 1.40-1.73; p < 0.0001) and the guideline-adherent group (HR, 1.18; 95% CI, 1.08-1.30; p = 0.0005). Disease-specific survival of the lowest socioeconomic status was worse in both the nonadherent group (HR, 1.42; 95% CI, 1.27-1.59) and the guideline-adherent group (HR, 1.20; 95% CI, 1.08-1.34).

LIMITATIONS

Limitations included unmeasured confounders and the retrospective nature of the review.

CONCLUSIONS

Race, socioeconomic status, and insurance are associated with guideline adherence in rectal cancer. Race/ethnicity was not associated with differences in disease-specific survival in the guideline-adherent group. Medicaid and lowest socioeconomic status had worse disease-specific survival in both the guideline nonadherent group and the guideline-adherent group. See Video Abstract at http://links.lww.com/DCR/B954 .

EFECTOS DIFERENCIALES DE LA RAZA, EL NIVEL SOCIOECONMICO COBERTURA SOBRE LA SUPERVIVENCIA ESPECFICA DE LA ENFERMEDAD EN EL CNCER DE RECTO

ANTECEDENTES: El cumplimiento de las guías de la National Comprehensive Cancer Network mejora los resultados del cáncer. En el cáncer de recto, el cumplimiento de las guías se distribuye de manera diferente según la raza/origen étnico, nivel socioeconómico y el cobertura médica.OBJETIVO: Determinar los efectos independientes de la raza/origen étnico, el nivel socioeconómico y el estado de cobertura médica en la supervivencia del cáncer de recto después de tener en cuenta las diferencias en el cumplimiento de las guías.DISEÑO: Este fue un estudio retrospectivo.ENTORNO CLINICO: El estudio se realizó utilizando el Registro de Cáncer de California.PACIENTES: Pacientes de 18 a 79 años diagnosticados con adenocarcinoma rectal entre el 1 de enero de 2004 y el 31 de diciembre de 2017 con seguimiento hasta el 30 de noviembre de 2018. Los investigadores determinaron si los pacientes recibieron atención siguiendo las guías.PRINCIPALES MEDIDAS DE RESULTADO: Se utilizaron razones de probabilidad e intervalos de confianza del 95 % para la regresión logística para analizar a los pacientes que recibían atención con adherencia a las guías. El análisis de supervivencia específico de la enfermedad se calculó utilizando modelos de regresión de Cox.RESULTADOS: Se analizaron un total de 30.118 pacientes. Los factores asociados con mayores probabilidades de cumplimiento de las guías incluyeron raza/etnicidad asiática e hispana, seguro de atención administrada y nivel socioeconómico alto. Los asiáticos e hispanos tuvieron una mejor supervivencia específica de la enfermedad en el grupo no adherente HR 0,80 (95 % CI 0,72 - 0,88, p < 0,001) y HR 0,91 (95 % CI 0,83 - 0,99, p = 0,0279). La raza o el origen étnico no fueron factores asociados con la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. La supervivencia específica de la enfermedad de Medicaid fue peor tanto en el grupo no adherente HR 1,56 (IC del 95 % 1,40 - 1,73, p < 0,0001) como en el grupo adherente a las guías HR 1,18 (IC del 95 % 1,08 - 1,30, p = 0,0005). La supervivencia específica de la enfermedad del nivel socioeconómico más bajo fue peor tanto en el grupo no adherente HR 1,42 (IC del 95 %: 1,27 a 1,59) como en el grupo adherente a las guías HR 1,20 (IC del 95 %: 1,08 a 1,34).LIMITACIONES: Las limitaciones incluyeron factores de confusión no medidos y la naturaleza retrospectiva de la revisión.CONCLUSIONES: La raza, el nivel socioeconómico y cobertura médica están asociados con la adherencia a las guías en el cáncer de recto. La raza/etnicidad no se asoció con diferencias en la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. Medicaid y el nivel socioeconómico más bajo tuvieron peor supervivencia específica de la enfermedad tanto en el grupo que no cumplió con las guías como en los grupos que cumplieron. Consulte Video Resumen en http://links.lww.com/DCR/B954 . (Traducción- Dr. Francisco M. Abarca-Rendon).

Development of a Machine Learning Model to Identify Colorectal Cancer Stage in Medicare Claims

PURPOSE

Staging information is essential for colorectal cancer research. Medicare claims are an important source of population-level data but currently lack oncologic stage. We aimed to develop a claims-based model to identify stage at diagnosis in patients with colorectal cancer.

METHODS

We included patients age 66 years or older with colorectal cancer in the SEER-Medicare registry. Using patients diagnosed from 2014 to 2016, we developed models (multinomial logistic regression, elastic net regression, and random forest) to classify patients into stage I-II, III, or IV on the basis of demographics, diagnoses, and treatment utilization identified in Medicare claims. Models developed in a training cohort (2014-2016) were applied to a testing cohort (2017), and performance was evaluated using cancer stage listed in the SEER registry as the reference standard.

RESULTS

The cohort of patients with 30,543 colorectal cancer included 14,935 (48.9%) patients with stage I-II, 9,203 (30.1%) with stage III, and 6,405 (21%) with stage IV disease. A claims-based model using elastic net regression had a scaled Brier score (SBS) of 0.45 (95% CI, 0.43 to 0.46). Performance was strongest for classifying stage IV (SBS, 0.62; 95% CI, 0.59 to 0.64; sensitivity, 93%; 95% CI, 91 to 94) followed by stage I-II (SBS, 0.45; 95% CI, 0.44 to 0.47; sensitivity, 86%; 95% CI, 85 to 76) and stage III (SBS, 0.32; 95% CI, 0.30 to 0.33; sensitivity, 62%; 95% CI, 61 to 64).

CONCLUSION

Machine learning models effectively classified colorectal cancer stage using Medicare claims. These models extend the ability of claims-based research to risk-adjust and stratify by stage.

The effect of medicare and screening guidelines on colorectal cancer outcomes

BACKGROUND

Colorectal cancer screening has been shown effective at reducing stage at presentation, but there is differential uptake of screening based on insurance status. We sought to determine the population-level effect of Medicare and screening guidelines on colorectal screening by race and region.

METHODS

Data on Black and white patients with colorectal cancer were obtained from the SEER database. Regression discontinuity was used to assess the causal effect of near-universal health insurance (represented by age 65) and United States Preventive Services Task Force guidelines (age 50) on the proportion of people presenting at advanced stage. This was stratified by race and region.

RESULTS

In the Southern United States, Black patients saw a significant decrease in advanced stage at presentation at age 65 (coefficient -0.12, p = 0.003), while white patients did not (coefficient -0.03, p = 0.09). At age 50, neither Black (coefficient 0.09, p = 0.10) nor white patients (coefficient -0.04, p = 0.1) saw a significant decrease in advanced stage. In the Western U.S., neither Black (coefficient 0.02, p = 0.72) or white patients (coefficient -0.02, p = 0.09) saw a significant decrease in advanced stage at age 65; however, both Black (coefficient -0.20, p = 0.008) and white patients (coefficient -0.05, p = 0.03) saw a significant decrease at age 50.

CONCLUSIONS

Our data highlight the significant impact that near-universal insurance has on reducing colorectal cancer stage at presentation in areas with poor baseline insurance coverage, particularly for Black patients. To reduce disparities in advanced stage at presentation for colorectal cancer, state-level insurance coverage should be addressed.

Racial and ethnic differences in retrospective end-of-Life outcomes: A systematic review

The purpose of this systematic review was to provide a comprehensive account of racial and ethnic differences in retrospective end-of-life outcomes. Studies were searched from the following databases: Abstracts in Social Gerontology, Academic Search Premier, CINAHL Plus with Full Text, ERIC, MEDLINE, PsycINFO, PubMED, and SocIndex. Studies were included if they were published in English, included people from groups who have been minoritized, included adults aged 18 and older, used retrospective data, and examined end-of-life outcomes. Results from most of the 29 included studies showed that people from groups who have been minoritized had more aggressive/intensive care, had less hospice care, were more likely to die in a hospital, less likely to engage in advance care planning, less likely to have good quality of care, and experienced more financial burden at the end of life. Implications for practice (timely referrals), policy (health insurance access), and research (intervention studies) are provided.

Disparities in colorectal cancer time-to-treatment and survival time associated with racial and economic residential segregation surrounding the diagnostic hospital, Georgia 2010-2015

PURPOSE

To evaluate patient-level colorectal cancer outcomes in relation to residential income and racial segregation and composition of the neighborhood surrounding the diagnosing hospitals, and characterize presence of cancer-relevant diagnosis and treatment modalities that might contribute to these associations.

METHODS

We utilized Georgia state cancer registry data (2010-2015), matching diagnosis information to hospital technology provided by the American Hospital Association and spatial information to the US Census. We modeled time-to-treatment and survival time, using Cox proportional hazards models, stratified by segregation. Segregation was examined as residential economic and racial evenness (Atkinson index) and isolation (isolation index) and mean income at the Census tract level. To assess possible contributing factors, analysis of hospital diagnosis and treatment technologies in relation to segregation was conducted.

RESULTS

Average income of the Census tract and racial residential segregation of the diagnosing hospital's neighborhood was generally unassociated with time-to-treatment or survival time. Higher income evenness around the diagnosing hospital was associated with shorter time-to-treatment, with no association with time-to-death. Higher income isolation for the diagnosing hospital, conversely, was associated with longer times to treatment, but also longer survival times. Hospitals in regions with higher level of residential income segregation were less likely to have a particular diagnosing or treatment technologies, such as virtual colonoscopy and chemotherapy.

CONCLUSION

Hospital resources may be a function of their immediate economic environment, and this may have influence on cancer outcomes. Future work should evaluate patient outcomes in light of technologies or therapies utilized within particular economic environments.

The Good Death Among Black, Indigenous, and/or People of Color: Which Aspects of a Good Death Are Most Important?

A good death is one where a patient's preferences and wishes are fully respected. The purpose of this study was to determine which aspects of a good death are most important to Black/Indigenous, and/or people of color (BIPOC). Participants were recruited from Amazon Mechanical Turk, and then directed to complete a quantitative survey indicating the importance of each item on the Good Death Inventory. A logistic regression model was used to identify any differences in the importance of each item based on the racial background of the respondent. After accounting for other independent variables, the results showed that BIPOC were more likely to indicate that factors such as life completion, receiving all treatment possible, and religious/spiritual support were important aspects of a good death. Results indicate the need for culturally tailored tools that account for cultural differences in what constitutes a good death.

Impact of the COVID-19 Pandemic on Treatment Patterns for Patients With Metastatic Solid Cancer in the United States

BACKGROUND

The COVID-19 pandemic has led to delays in patients seeking care for life-threatening conditions; however, its impact on treatment patterns for patients with metastatic cancer is unknown. We assessed the COVID-19 pandemic's impact on time to treatment initiation (TTI) and treatment selection for patients newly diagnosed with metastatic solid cancer.

METHODS

We used an electronic health record-derived longitudinal database curated via technology-enabled abstraction to identify 14 136 US patients newly diagnosed with de novo or recurrent metastatic solid cancer between January 1 and July 31 in 2019 or 2020. Patients received care at approximately 280 predominantly community-based oncology practices. Controlled interrupted time series analyses assessed the impact of the COVID-19 pandemic period (April-July 2020) on TTI, defined as the number of days from metastatic diagnosis to receipt of first-line systemic therapy, and use of myelosuppressive therapy.

RESULTS

The adjusted probability of treatment within 30 days of diagnosis was similar across periods (January-March 2019 = 41.7%, 95% confidence interval [CI] = 32.2% to 51.1%; April-July 2019 = 42.6%, 95% CI = 32.4% to 52.7%; January-March 2020 = 44.5%, 95% CI = 30.4% to 58.6%; April-July 2020 = 46.8%, 95% CI= 34.6% to 59.0%; adjusted percentage-point difference-in-differences = 1.4%, 95% CI = -2.7% to 5.5%). Among 5962 patients who received first-line systemic therapy, there was no association between the pandemic period and use of myelosuppressive therapy (adjusted percentage-point difference-in-differences = 1.6%, 95% CI = -2.6% to 5.8%). There was no meaningful effect modification by cancer type, race, or age.

CONCLUSIONS

Despite known pandemic-related delays in surveillance and diagnosis, the COVID-19 pandemic did not affect TTI or treatment selection for patients with metastatic solid cancers.

Racial Disparities in the Management of Locoregional Colorectal Cancer

Racial disparities pervade nearly all aspects of management of locoregional colorectal cancer, including time to treatment, receipt of resection, adequacy of resection, postoperative complications, and receipt of neoadjuvant and adjuvant multimodality therapies. Disparate gaps in treatment translate into enduring effects on survivorship, recurrence, and mortality. Efforts to reduce these gaps in care must be undertaken on a multilevel basis and focus on modifiable factors that underlie racial disparity.

All-cause mortality and residential racial and ethnic segregation and composition as experienced differently by individual-level race, ethnicity, and gender: Mortality disparities in american communities data

PURPOSE

Use a large nationally representative population to evaluate whether differences in mortality in relation to residential racial and ethnic segregation and diversity varied by gender, and race or Hispanic ethnicity in the United States.

METHODS

The Mortality Disparities in American Communities (MDAC) was used to evaluate mortality risk in relation to segregation. MDAC is a nationally representative record linkage of the 2008 American Community Survey data with mortality outcomes derived from the National Death Index through 2015. Gender-stratified mortality risk for White, Black, and Hispanic groups in relation to quartiles of residential segregation, composition, and diversity were modeled using parametric survival regression with an exponential distribution, adjusted for individual-level socioeconomic characteristics.

RESULTS

The study population included >3,950,000 individuals and >273,000 all-cause mortality outcomes. Statistically significant differences in associations were observed with Black segregation vs. Hispanic segregation across Black or Hispanic groups; some differences in stratification by gender for Hispanic and Non-Hispanic Black groups, but gender-stratified associations were more similar in non-Hispanic Whites.

CONCLUSIONS

Future multidisciplinary and ethnographic research is needed to identify the specific structural mechanisms by which these associations differ to support means by which to more effectively target public health interventions.

Impact of the COVID-19 pandemic on treatment patterns for US patients with metastatic solid cancer

BACKGROUND

The COVID-19 pandemic has led to delays in patients seeking care for life-threatening conditions; however, its impact on treatment patterns for patients with metastatic cancer is unknown. We assessed the COVID-19 pandemic's impact on time to treatment initiation (TTI) and treatment selection for patients newly diagnosed with metastatic solid cancer.

METHODS

We used an electronic health record-derived longitudinal database curated via technology-enabled abstraction to identify 14,136 US patients newly diagnosed with de novo or recurrent metastatic solid cancer between January 1 and July 31 in 2019 or 2020. Patients received care at ∼280 predominantly community-based oncology practices. Controlled interrupted time series analyses assessed the impact of the COVID-19 pandemic period (April-July 2020) on TTI, defined as the number of days from metastatic diagnosis to receipt of first-line systemic therapy, and use of myelosuppressive therapy.

RESULTS

The adjusted probability of treatment within 30 days of diagnosis [95% confidence interval] was similar across periods: January-March 2019 41.7% [32.2%, 51.1%]; April-July 2019 42.6% [32.4%, 52.7%]; January-March 2020 44.5% [30.4%, 58.6%]; April-July 2020 46.8% [34.6%, 59.0%]; adjusted percentage-point difference-in-differences 1.4% [-2.7%, 5.5%]. Among 5,962 patients who received first-line systemic therapy, there was no association between the pandemic period and use of myelosuppressive therapy (adjusted percentage-point difference-in-differences 1.6% [-2.6%, 5.8%]). There was no meaningful effect modification by cancer type, race, or age.

CONCLUSIONS

Despite known pandemic-related delays in surveillance and diagnosis, the COVID-19 pandemic did not impact time to treatment initiation or treatment selection for patients with metastatic solid cancers.

The Impact of Racial Residential Segregation on Colorectal Cancer Outcomes and Treatment

OBJECTIVE

We sought to examine the impact of racial residential segregation on Black-White disparities in colorectal cancer diagnosis, surgical resection, and cancer-specific survival.

SUMMARY BACKGROUND DATA

There are clear Black-White disparities in colorectal cancer diagnosis and treatment with equally disparate explanations for these findings, including genetics, socioeconomic factors, and health behaviors.

METHODS

Data on Black and White patients with colorectal cancer were obtained from SEER between 2005 and 2015. The exposure of interest was the index of dissimilarity (IoD), a validated measure of segregation derived from 2010 Census data. Outcomes included advanced stage at diagnosis (AJCC stage IV), resection of localized disease (AJCC stage I-II), and cancer-specific survival. We used Poisson regression with robust error variance for the outcomes of interest and Cox proportional hazards were used to assess cancer-specific 5-year survival.

RESULTS

Black patients had a 41% increased risk of presenting at advanced stage per IoD [risk ratio (RR) 1.41, 95% confidence intervals (CI) 1.18, 1.69] and White patients saw a 17% increase (RR 1.17, 95%CI 1.04, 1.31). Black patients were 5% less likely to undergo surgical resection (RR 0.95, 95%CI 0.90, 0.99), whereas Whites were 5% more likely (RR 1.05, 95%CI 1.03, 1.07). Black patients had 43% increased hazards of cancer-specific mortality with increasing IoD (hazard ratio (HR) 1.43, 95%CI 1.17, 1.74).

CONCLUSIONS

Black patients with colorectal cancer living in more segregated counties are significantly more likely to present at advanced stage and have worse cancer-specific survival. Enduring structural racism in the form of residential segregation has strong impacts on the colorectal cancer outcomes.

Longer time-to-treatment but better survival for colorectal cancer patients presumptively not diagnosed in a hospital

PURPOSE

To evaluate time-to-treatment and survival time in colorectal cancer (CRC) patients who presumptively were not diagnosed in a hospital.

METHODS

Colorectal tumor-level data from Georgia Cancer Registry (GCR) was merged with American Hospital Association data for 2010-2015 using hospital identification number. Patients with tumors lacking a diagnosis hospital in the GCR were classified as presumptive non-hospital diagnosis (PNHD). Cox proportional hazard models were used to model PNHD and time-to-treatment and time-to-death following cancer diagnosis, stratified by race and controlling for personal and tumor characteristics.

RESULTS

PNHD (n = 6,885, 29.6%) was associated with a lower likelihood of treatment at a given point in time (i.e., longer time-to-treatment), but did not differ for Black (HR = 0.77, 95% CI: 0.73, 0.82) and White (HR = 0.73, 95% CI: 0.71, 0.76) patients. Time-to-death was longer (i.e., better survival) with PNHD, which also did not differ for Black (HR = 0.70, 95% CI: 0.64, 0.76) and White (HR = 0.71, 95% CI: 0.67, 0.75) patients. These results were not explained by confounding factors or differences in tumor stage at diagnosis.

CONCLUSIONS

These observations warrant further research to understand whether there are potentially modifiable factors associated with the diagnosing location that can be used to benefit patient treatment trajectory and survival.

A National Study of Colorectal Cancer Survivorship Disparities: A Latent Class Analysis Using SEER (Surveillance, Epidemiology, and End Results) Registries

Introduction: Long-standing disparities in colorectal cancer (CRC) outcomes and survival between Whites and Blacks have been observed. A person-centered approach using latent class analysis (LCA) is a novel methodology to assess and address CRC health disparities. LCA can overcome statistical challenges from subgroup analyses that would normally impede variable-centered analyses like regression. Aim was to identify risk profiles and differences in malignant CRC survivorship outcomes. Methods: We conducted an LCA on the Surveillance, Epidemiology, and End Results data from 1975 to 2016 for adults ≥18 (N = 525,245). Sociodemographics used were age, sex/gender, marital status, race, and ethnicity (Hispanic/Latinos) and stage at diagnosis. To select the best fitting model, we employed a comparative approach comparing sample-size adjusted BIC and entropy; which indicates a good separation of classes. Results: A four-class solution with an entropy of 0.72 was identified as: lowest survivorship, medium-low, medium-high, and highest survivorship. The lowest survivorship class (26% of sample) with a mean survival rate of 53 months had the highest conditional probabilities of being 76-85 years-old at diagnosis, female, widowed, and non-Hispanic White, with a high likelihood with localized staging. The highest survivorship class (53% of sample) with a mean survival rate of 92 months had the highest likelihood of being married, male with localized staging, and a high likelihood of being non-Hispanic White. Conclusion: The use of a person-centered measure with population-based cancer registries data can help better detect cancer risk subgroups that may otherwise be overlooked.