Significant Racial Disparities Exist in Noncardia Gastric Cancer Outcomes Among Kaiser Permanente's Patient Population

Genomic ancestry and cancer among Latin Americans

Latin American populations, characterized by intricate admixture patterns resulting from the intermingling of ancestries from European, Native American (NA) Asian, and African ancestries which result in a vast and complex genetic landscape, harboring unique combinations of novel variants. This genetic diversity not only poses challenges in traditional population genetics methods but also opens avenues for a deeper understanding of its implications in health. In cancer, the interplay between genetic ancestry, lifestyle factors, and healthcare disparities adds a layer of complexity to the varying incidence and mortality rates observed across different Latin American subpopulations. This complex interdependence has been unveiled through numerous studies, whether conducted on Latin American patients residing on the continent or abroad, revealing discernible differences in germline composition that influence divergent disease phenotypes such as higher incidence of Luminal B and Her2 breast tumors, EGFR and KRAS mutated lung adenocarcinomas in addition to an enrichment in BRCA1/2 pathogenic variants and a higher than expected prevalence of variants in colorectal cancer associated genes such as APC and MLH1. In prostate cancer novel risk variants have also been solely identified in Latin American populations. Due to the complexity of genetic divergence, inputs from each individual ancestry seem to carry independent contributions that interplay in the development of these complex disease phenotypes. By understanding these unique population characteristics, genomic ancestries hold a promising avenue for tailoring prognostic assessments and optimizing responses to oncological interventions.

Socioeconomic disparities and the genomic landscape of gastric cancer

The genomic characteristics of Peruvian patients with gastric adenocarcinoma from diverse socioeconomic backgrounds were examined in consideration of the possibility that patients from different socioeconomic backgrounds may be exposed to different risk factors. We conducted a prospective pilot study in two Peruvian cities (Lima and Ica). This study enrolled 15 patients from low socioeconomic status (LSES) and 15 patients from medium/high socioeconomic status (MHSES). The genomic profiling of gastric adenocarcinoma samples was done through the FoundationOne CDx platform. We compared the genomic characteristics and the need for targeted therapy and immunotherapy between LSES and MHSES. The genes with higher rates of alterations were TP53 (73.3% vs. 50.0%, P = 0.2635); CDH1 (26.7% vs. 28.6%, P = 1); CDKN2A (20.0% vs. 28.6%, P = 1); KRAS (33.3% vs. 7.1%, P = 0.1686); ARID1A (20.0% vs. 14.3%, P = 1); MLL2 (13.3% vs. 21.4%, P = 1) and SOX9 (33.3% vs. 0.0%, P = 0.0421) in LSES versus HMSES, respectively. There was no significant difference in tumor mutational burden (P = 0.377) or microsatellite status (P = 1). The LSES group had a higher need for targeted therapy or immunotherapy according to gene involvement and alterations. A significant genomic difference exists among patients with gastric adenocarcinoma of different socioeconomic status, which may result in a different need for targeted therapy and immunotherapy.

Study Protocol: A Mixed-Methods Study for Understanding Racial Disparities in COVID-19-Related Complications

Background

In the United States, the COVID-19 pandemic has magnified the disproportionate and long-standing health disparities experienced by Black communities. Although it is acknowledged that social determinants of health (SDOH) rather than biological factors likely contribute to this disparity, few studies using rigorous analytic approaches in large, information-rich community-based data sets are dedicated to understanding the underlying drivers of these racial disparities.

Objective

The overall aim of our study is to elucidate the mechanisms by which racial disparities in severe COVID-19 outcomes arise, using both quantitative and qualitative methods.

Methods

In this protocol, we outline a convergent parallel mixed methods approach to identifying, quantifying, and contextualizing factors that contribute to the dramatic disparity in COVID-19 severity (ie, hospitalization, mortality) in Black versus white COVID-19 patients within the integrated health care system of Kaiser Permanente Georgia (KPGA). Toward this end, we will generate two quantitative cohorts of KPGA members with a confirmed COVID-19 diagnosis between January 1, 2020, and September 30, 2021: (1) an electronic medical record (EMR) cohort including routinely captured data on diagnoses, medications, and laboratory values, and a subset of patients hospitalized at Emory Healthcare to capture additional in-hospital data; and (2) a survey cohort, where participants will answer a range of questions related to demographics (eg, race, education), usual health behaviors (eg, physical activity, smoking), impact of COVID-19 (eg, job loss, caregiving responsibilities), and medical mistrust. Key outcomes of interest for these two cohorts include hospitalization, mortality, intensive care unit admission, hospital readmission, and long COVID-19. Finally, we will conduct qualitative semistructured interviews to capture perceptions of and experiences of being hospitalized with COVID-19 as well as related interactions with KPGA health care providers. We will analyze and interpret the quantitative and qualitative data separately, and then integrate the qualitative and quantitative findings using a triangulation design approach.

Results

This study has been funded by a Woodruff Health Sciences grant from December 2020 to December 2022. As of August 31, 2022, 31,500 KPGA members diagnosed with COVID-19 have been included in the EMR cohort, including 3028 who were hospitalized at Emory Healthcare, and 482 KPGA members completed the survey. In addition, 20 KPGA members (10 Black and 10 white) have been interviewed about their experiences navigating care with COVID-19. Quantitative and qualitative data cleaning and coding have been completed. Data analysis is underway with results anticipated to be published in December 2022.

Conclusions

Results from this mixed methods pilot study in a diverse integrated care setting in the southeastern United States will provide insights into the mechanisms underpinning racial disparities in COVID-19 complications. The quantitative and qualitative data will provide important context to generate hypotheses around the mechanisms for racial disparities in COVID-19, and may help to inform the development of multilevel strategies to reduce the burden of racial disparities in COVID-19 and its ongoing sequelae. Incorporating contextual information, elucidated from qualitative interviews, will increase the efficacy, adoption, and sustainability of such strategies.

International Registered Report Identifier (IRRID)

RR1-10.2196/38914

Positive H. pylori status predicts better prognosis of non-cardiac gastric cancer patients: results from cohort study and meta-analysis

BACKGROUND

Previous researches have associated Helicobacter pylori (H. pylori) with a prognosis of gastric cancer (GC), however, without a concert conclusion. This study aimed to study this issue further by a prospective cohort study and a meta-analysis.

METHODS

Histologically diagnosed gastric cancer (GC) patients were recruited into the primary prospective cohort study between January 2009 to December 2013. All the patients were followed-up periodically to record information on post-surgery therapy and overall survival status. The pre-surgery status of H. pylori was measured by enzyme-linked immunosorbent assay. A meta-analysis was conducted after retrieving related researches in the databases of PubMed and Embase up to April 2020. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were summarized to validate the relationship between H. pylori infection and the survival time of GC patients. I² statistics and Q test were used to assess the heterogeneity. Sensitivity analyses were performed using Galbraith's plot, leave-one-out analysis, subgroup analyses and meta-regression to explore the sources of heterogeneity and the stability of the summary results.

RESULTS

A total of 743 GC patients with radical tumorectomy were included prospectively and 516 (69.4%) were positive on H. pylori. H. pylori-positive patients tended to survive longer than -negative ones (HR 0.92, 95%CI: 0.74-1.15), though the tendency was not statistically significant. Cohort studies on the prognosis of GC were retrieved comprehensively by assessing the full-text and 59 published studies, together with the result of our study, were included in the further meta-analysis. The summarized results related the positive status of H. pylori to better overall survival (HR 0.81, 95%CI: 0.72-0.90) and disease-free survival (HR 0.83, 95%CI: 0.67-0.99). Results from subgroup analyses indicated that the pooled magnitude of this association was relatively lower in studies not referring to H. pylori in title and abstract.

CONCLUSIONS

In conclusion, gastric cancer patients with H. pylori have a better prognosis than patients of H. pylori negative. More stringent surveillance strategies may be necessary for patients with H. pylori negative at cancer diagnosis.

The presentation of Hispanic gastric cancer patients varies by location of patient ancestry

BACKGROUND AND OBJECTIVES

The clinical presentation of gastric cancer varies between racial and ethnic groups. While historically studied as a monolithic population, the Hispanic ethnicity is comprised of heterogenous groups with considerable biologic, socioeconomic, and cultural variability; therefore, intragroup differences among Hispanic gastric cancer patients may have been overlooked in past research.

METHODS

We conducted a retrospective review of the National Cancer Database (NCDB) to compare Hispanic patients with gastric adenocarcinoma diagnosed between 2004 and 2015, by NCDB-reported location of patient ancestry.

RESULTS

We identified a cohort of 3811 patients. There were higher proportions of females, patients with early disease onset, and stage 4 disease among patients of Mexican and South/Central American ancestry. Additionally, a significantly larger proportion of Mexican (15%) and South/Central American patients (11%) were diagnosed before age 40, in contrast to Cubans (2%), Dominicans (6%), and Puerto Ricans (3%; p < 0.0001). Mexican ancestry was independently associated with an increased rate of all-cause mortality at 5 years (hazard ratio: 1.34; 95% confidence interval: 1.09-1.64).

CONCLUSIONS

Significant clinical and epidemiological differences exist among Hispanic gastric cancer patients based on location of ancestry. Future data collection endeavors should strive to capture this granularity inherent to the Hispanic ethnicity.

Hispanic/Latino Patients with Gastric Adenocarcinoma Have Distinct Molecular Profiles Including a High Rate of Germline CDH1 Variants

Hispanic/Latino patients have a higher incidence of gastric cancer and worse cancer-related outcomes compared with patients of other backgrounds. Whether there is a molecular basis for these disparities is unknown, as very few Hispanic/Latino patients have been included in previous studies. To determine the genomic landscape of gastric cancer in Hispanic/Latino patients, we performed whole-exome sequencing (WES) and RNA sequencing on tumor samples from 57 patients; germline analysis was conducted on 83 patients. The results were compared with data from Asian and White patients published by The Cancer Genome Atlas. Hispanic/Latino patients had a significantly larger proportion of genomically stable subtype tumors compared with Asian and White patients (65% vs. 21% vs. 20%, P < 0.001). Transcriptomic analysis identified molecular signatures that were prognostic. Of the 43 Hispanic/Latino patients with diffuse-type cancer, 7 (16%) had germline variants in CDH1. Variant carriers were significantly younger than noncarriers (41 vs. 50 years, P < 0.05). In silico algorithms predicted five variants to be deleterious. For two variants that were predicted to be benign, in vitro modeling demonstrated that these mutations conferred increased migratory capability, suggesting pathogenicity. Hispanic/Latino patients with gastric cancer possess unique genomic landscapes, including a high rate of CDH1 germline variants that may partially explain their aggressive clinical phenotypes. Individualized screening, genetic counseling, and treatment protocols based on patient ethnicity and race may be necessary. SIGNIFICANCE: Gastric cancer in Hispanic/Latino patients has unique genomic profiles that may contribute to the aggressive clinical phenotypes seen in these patients.

Sex difference in incidence of gastric cancer: an international comparative study based on the Global Burden of Disease Study 2017

OBJECTIVES

To investigate sex difference in global gastric cancer incidence by year, age and socioeconomical status.

DESIGN

An international comparative study.

SETTING

We obtained the global and national sex-specific incidence of gastric caner by year and age from the Global Burden of Disease Study 2017. The human development index (HDI) in 2017 as an indicator of national socioeconomical status was extracted from the Human Development Report.

MAIN OUTCOME MEASURES

Sex-specific incidence of gastric cancer was compared by year and age at the global level. Linear regression analyses were performed to explore socioeconomic-associated sex difference in gastric cancer incidence.

RESULTS

Despite declining incidence of global gastric cancer in both sexes between 1990 and 2017, relative sex difference showed an increasing trend, with male to female ratios of age-standardised incidence rates (ASRs) rising from 1.86 to 2.20. Sex difference was almost negligible under 45 years of age and relative difference maximised in the age range of 65-69 years with male to female ratios of ASRs being 2.74. Both absolute sex difference (standardised β=0.256, p<0.001) and relative difference (standardised β=0.387, p<0.001) in ASRs were positively associated with HDI.

CONCLUSIONS

This study revealed that decreasing incidence of global gastric cancer was accompanied by widening sex difference in the past few decades. Men always had higher incidence than women. Greater sex difference was found in older age and in more developed countries. These findings highlight the importance of making sex-sensitive health policy to cope with the global gastric cancer burden.

Socio-Demographic Disparities in Gastric Adenocarcinoma: A Population-Based Study

Background: Gastric cancer is one of the leading causes of cancer-related mortality worldwide, accounting for 8.2% of cancer-related deaths. The purpose of this study was to investigate the geographic and sociodemographic disparities in gastric adenocarcinoma patients.

METHODS

We conducted a retrospective study in gastric adenocarcinoma patients between 2004 and 2013. Data were obtained from the National Cancer Data Base (NCDB). Univariate and multivariable analyses were performed to evaluate overall survival (OS). Socio-demographic factors, including the location of residence [metro area (MA) or rural area (RA)], gender, race, insurance status, and marital status, were analyzed.

RESULTS

A total of 88,246 [RA, N = 12,365; MA, N = 75,881] patients were included. Univariate and multivariable analysis showed that RA had worse OS (univariate HR = 1.08, p < 0.01; multivariate HR = 1.04; p < 0.01) compared to MA. When comparing different racial backgrounds, Native American and African American populations had poorer OS when compared to the white population; however, Asian patients had a better OS (multivariable HR = 0.68, p < 0.01). From a quality of care standpoint, MA patients had fewer median days to surgery (28 vs. 33; p < 0.01) with fewer positive margins (6.3% vs. 6.9%; p < 0.01) when compared to RA patients. When comparing the extent of lymph node dissection, 19.6% of MA patients underwent an extensive dissection (more than or equal to 15 lymph nodes) in comparison to 18.7% patients in RA (p = 0.03).

DISCUSSION

This study identifies socio-demographic disparities in gastric adenocarcinoma. Future health policy initiatives should focus on equitable allocation of resources to improve the outcomes.

The impact of race and socioeconomic status on the presentation, management and outcomes for gastric cancer patients: Analysis from a metropolitan area in the southeast United States

BACKGROUND

Socioeconomic disparities in gastric cancer have been associated with differences in care and inferior outcomes. We evaluated the presentation, treatment, and survival for patients with gastric cancer (GC) in a metropolitan setting with a large African American population.

METHODS

Retrospective cohort analysis of patients with GC (2003-2018) across a multi-hospital system was performed. Associations between socioeconomic and clinicopathologic data with the presentation, treatment, and survival were examined.

RESULTS

Of 359 patients, 255 (71%) were African American and 104 (29%) Caucasian. African Americans were more likely to present at a younger age (64.0 vs 72.5, P < .001), have state-sponsored or no insurance (19.7% vs 6.9%, P = .02), reside within the lowest 2 quintiles for median income (67.4% vs 32.7%, P < .001), and have higher rates of Helicobacter pylori (14.9% vs 4.8%, P = .02). Receipt of multi-modality therapy was not impacted by race or insurance status. On multivariable analysis, only AJCC T class (HR 1.68) and node positivity (HR 2.43) remained significant predictors of disease-specific survival.

CONCLUSION

Despite socioeconomic disparities, African Americans, and Caucasians with GC had similar treatment and outcomes. African Americans presented at a younger age with higher rates of H. pylori positivity, warranting further investigation into differences in risk factors and tumor biology.

Gastric Cancer: Recent Molecular Classification Advances, Racial Disparity, and Management Implications

Gastric adenocarcinoma remains an aggressive and poorly understood malignancy with a heterogeneous presentation and tumor biology. The current histologic and anatomic classification has been ineffective in guiding therapy, with only marginal improvement in outcome over time. Furthermore, the variation in presentation and disease among racial and ethnic groups amplifies the complexity of this cancer. An understanding of the clinical and molecular variability is important for effective treatment. Recent advances in molecular biology have better defined gastric cancer subtypes. We systematically review recent literature on the molecular classification of gastric adenocarcinoma and the associated management implications, with an emphasis on Hispanic and Native American populations.

Personalized medicine and Hispanic health: improving health outcomes and reducing health disparities - a National Heart, Lung, and Blood Institute workshop report

Persons of Hispanic/Latino descent may represent different ancestries, ethnic and cultural groups and countries of birth. In the U.S., the Hispanic/Latino population is projected to constitute 29% of the population by 2060. A personalized approach focusing on individual variability in genetics, environment, lifestyle and socioeconomic determinants of health may advance the understanding of some of the major factors contributing to the health disparities experienced by Hispanics/Latinos and other groups in the U.S., thus leading to new strategies that improve health care outcomes. However, there are major gaps in our current knowledge about how personalized medicine can shape health outcomes among Hispanics/Latinos and address the potential factors that may explain the observed differences within this heterogeneous group, and between this group and other U.S. demographic groups. For that purpose, the National Heart, Lung, and Blood Institute (NHLBI), in collaboration with the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), and the Food and Drug Administration (FDA), held a workshop in which experts discussed (1) potential approaches to study medical treatments and health outcomes among Hispanics/Latinos and garner the necessary evidence to fill gaps of efficacy, effectiveness and safety of therapies for heart, lung, blood and sleep (HLBS) disorders and conditions--and their risk factors; (2) research opportunities related to personalized medicine to improve knowledge and develop effective interventions to reduce health disparities among Hispanics/Latinos in the U.S.; and (3) the incorporation of expanded sociocultural and socioeconomic data collection and genetic/genomic/epigenetic information of Hispanic/Latino patients into their clinical assessments, to account for individual variability in ancestry; physiology or disease risk; culture; environment; lifestyle; and socioeconomic determinants of health. The experts also provided recommendations on: sources of Hispanic/Latino health data and strategies to enhance its collection; policy; genetics, genomics and epigenetics research; and integrating Hispanic/Latino health research within clinical settings.

Risks and Predictors of Gastric Adenocarcinoma in Patients with Gastric Intestinal Metaplasia and Dysplasia: A Population-Based Study

OBJECTIVES

Gastric intestinal metaplasia and dysplasia are precursor lesions for adenocarcinoma. The risks of progression to malignancy from these lesions are not well characterized, particularly in the US populations.

METHODS

We identified 4,331 Kaiser Permanente Northern California members who were diagnosed with gastric intestinal metaplasia or dysplasia between 1997 and 2006 and followed them through December 2013. The incident rates of gastric adenocarcinoma, relative risks in comparison with the Kaiser Permanente general population, and predictors of progression to malignancy were investigated.

RESULTS

Among 4,146 individuals with gastric intestinal metaplasia and 141 with low-grade dysplasia with 24,440 person-years follow-up, 17 and 6 cases of gastric adenocarcinoma were diagnosed, respectively, after 1 year from the index endoscopy. The incidence rate of gastric adenocarcinoma was 0.72/1,000 person-years in patients with intestinal metaplasia, with a relative risk of 2.56 (95% confidence interval (CI) 1.49-4.10) compared with the Kaiser Permanente member population, and 7.7/1,000 person-years for low-grade dysplasia, with a relative risk of 25.6 (95% CI, 9.4-55.7). The median time for gastric intestinal metaplasia to progress to adenocarcinoma was 6.1 years, and for low-grade dysplasia, 2.6 years. Hispanic race/ethnicity and history of dysplasia were associated with significantly higher risk of progression to gastric adenocarcinoma.

CONCLUSIONS

Gastric intestinal metaplasia and dysplasia are significant predictors for gastric adenocarcinoma. The low risk for malignancy associated with intestinal metaplasia does not support routine endoscopic surveillance. However, surveillance should be considered in patients at higher risks, including those with suspicious endoscopic features, presence of dysplasia, and Hispanic race/ethnicity.