Disparities In Lung Cancer Incidence Research Articles

Abstract 4821: Lung cancer survival disparities by ethnicity in Guam, 2001-2020

Abstract Background: Lung cancer is the leading cause of cancer-related deaths in Guam, with a significantly higher mortality rate compared to the United States (46.9 vs 40.2 per 100,000), despite a lower incidence rate (50.9 vs 52.6 respectively, for the years 2013-2017). There are significant ethnic disparities in lung cancer incidence and mortality rates, with CHamoru (indigenous people) and Micronesian (immigrants from other Micronesian Islands) populations being disproportionately affected compared to other ethnic groups. This study aims to assess lung cancer survival rates in Guam and explore how demographic and other factors impact these rates. Methods: This study included 1171 patients diagnosed with invasive lung cancer and reported to the Guam Cancer Registry from 2001-2020. Five-year and 10-year survival rates were calculated using the Kaplan-Meier method and were compared using the log-rank test across different ethnic groups: CHamoru (N = 613), Filipino (N = 245), Asian (N = 74), Micronesian (N = 110), and Caucasian (N = 82). The Cox proportional hazards regression was used to investigate the effects of sex, age, year of diagnosis, ethnicity, lung cancer staging, and cancer treatment status on the risk of all-cause mortality. Results: Mean age at diagnosis was 65.75 years. Of the cases, only 10.8% were identified at an early stage, 43.1% at a late stage, and 46.0% unstaged. Significant differences in the 5-year and 10-year survival rates were found across ethnic groups. CHamoru had the lowest 5-year (15.6%) and 10-year survival rates (13.2%) followed by Micronesian (18.7% and 17.2%, respectively). All-cause mortality was higher among CHamoru (HR = 1.54, 95% CI: 1.28, 1.85) and Micronesian (HR=1.51, 95% CI: 1.15, 1.98) compared with Filipino after adjusting for age, sex, year of diagnosis, staging, and cancer treatment status. There were no statistically significant differences in all-cause mortality between Asian and Caucasian patients and Filipino patients. Cancer staging also indicated a significantly higher hazard rate for late-stage patients (HR = 1.78, 95% CI: 1.41, 2.25) and un-staged patients (HR = 1.51, 95% CI: 1.18, 1.94) compared to early-stage patients. Additionally, patients who did not receive any treatment (HR = 1.46, 95% CI: 1.22-1.74) and those with unknown treatment status (HR = 1.40, 95% CI: 1.17-1.68) experienced higher hazard rates than those who received at least one form of treatment. Conclusion: The predominance of late-stage or unstaged diagnoses in this study highlights a significant gap in early lung cancer detection in Guam. Survival rates for the CHamoru and Micronesian populations are notably lower than those observed in the U.S. These findings underscore the critical need for expanded lung cancer screening initiatives in Guam to facilitate earlier diagnosis and potentially improve survival outcomes. Acknowledgement: This study was supported by the PIPCHE/U54 Grant (U54CA143728). Citation Format: Cruz Aurienne, Louis J. Dulana, Rodney Teria, Grazyna Badowski. Lung cancer survival disparities by ethnicity in Guam, 2001-2020 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4821.

Geographical Disparities in Lung Cancer in Canada: A Review.

The eastern provinces of Canada exhibit a heightened prevalence and mortality rate of lung cancer compared to their western counterparts. While established risk factors for lung cancer exist in Canada, there remains ambiguity regarding the underlying provincial and territorial trends. This review aims to identify and analyze potential contributors to healthcare inequality, guiding policymakers towards a strategic and sustainable approach at the provincial level. Existing studies emphasize the significant roles played by socio-economic and environmental factors in influencing lung cancer disparities across Canadian provinces. However, a noticeable research gap persists, particularly in systematically examining the factors that amplify geographical disparities in lung cancer incidence and mortality rates within Canada. This review underscores the disparities in lung cancer prevalence and mortality rates between eastern and western Canadian provinces. While socio-economic and environmental factors have been identified as influential, there is an evident need for further research to comprehensively understand and address the underlying contributors to these geographical discrepancies.

Structural Racism as a Contributor to Lung Cancer Incidence and Mortality Rates Among Black Populations in the United States.

Although racial disparities in lung cancer incidence and mortality have diminished in recent years, lung cancer remains the second most diagnosed cancer among US Black populations. Many factors contributing to disparities in lung cancer are rooted in structural racism. To quantify this relationship, we examined associations between a multidimensional measure of county-level structural racism and county lung cancer incidence and mortality rates among Black populations, while accounting for county levels of environmental quality. We merged 2016-2020 data from the United States Cancer Statistics Data Visualization Tool, a pre-existing county-level structural racism index, the Environmental Protection Agency's 2006-2010 Environmental Quality Index (EQI), 2023 County Health Rankings, and the 2021 United States Census American Community Survey. We conducted multivariable linear regressions to examine associations between county-level structural racism and county-level lung cancer incidence and mortality rates. Among Black males and females, each standard deviation increase in county-level structural racism score was associated with an increase in county-level lung cancer incidence of 6.4 (95% CI: 4.4, 8.5) cases per 100,000 and an increase of 3.3 (95% CI: 2.0, 4.6) lung cancer deaths per 100,000. When examining these associations stratified by sex, larger associations between structural racism and lung cancer rates were observed among Black male populations than among Black females. Structural racism contributes to both the number of new lung cancer cases and the number of deaths caused by lung cancer among Black populations. Those aiming to reduce lung cancer cases and deaths should consider addressing racism as a root-cause.

Gender disparities in lung cancer incidence in the United States during 2001–2019

Lung cancer ranks as one of the top malignancies and the leading cause of cancer death in both males and females in the US. Using a cancer database covering the entire population, this study was to determine the gender disparities in lung cancer incidence during 2001–2019. Cancer patients were obtained from the National Program of Cancer Registries (NPCR) and Surveillance, Epidemiology and End Results (SEER) database. The SEER*Stat software was applied to calculate the age-adjusted incidence rates (AAIR). Temporal changes in lung cancer incidence were analyzed by the Joinpoint software. A total of 4,086,432 patients (53.3% of males) were diagnosed with lung cancer. Among them, 52.1% were 70 years or older, 82.7% non-Hispanic white, 39.7% from the South, and 72.6% non-small cell lung cancer (NSCLC). The AAIR of lung cancer continuously reduced from 91.0 per 100000 to 59.2 in males during the study period, while it increased from 55.0 in 2001 to 56.8 in 2006 in females, then decreased to 48.1 in 2019. The female to male incidence rate ratio of lung cancer continuously increased from 2001 to 2019. Gender disparities were observed among age groups, races, and histological types. In those aged 0–54 years, females had higher overall incidence rates of lung cancer than males in recent years, which was observed in all races (except non-Hispanic black), all regions, and adenocarcinoma and small cell (but not squamous cell). Non-Hispanic black females aged 0–54 years had a faster decline rate than males since 2013. API females demonstrated an increased trend during the study period. Lung cancer incidence continues to decrease with gender disparities among age groups, races, regions, and histological types. Continuous anti-smoking programs plus reduction of related risk factors are necessary to lower lung cancer incidence further.

Sex Differences in Lung Cancer

Sex disparities in the incidence and mortality of lung cancer have been observed since cancer statistics have been recorded. Social and economic differences contribute to sex disparities in lung cancer incidence and mortality, but evidence suggests that there are also underlying biological differences that contribute to the disparity. This review summarizes biological differences which could contribute to the sex disparity. Sex hormones and other biologically active molecules, tumor cell genetic differences, and differences in the immune system and its response to lung cancer are highlighted. How some of these differences contribute to disparities in the response to therapies, including cytotoxic, targeted, and immuno-therapies, is also discussed. We end the study with a discussion of our perceived future directions to identify the key biological differences which could contribute to sex disparities in lung cancer and how these differences could be therapeutically leveraged to personalize lung cancer treatment to the individual sexes.

Understanding Racial Differences in Lung Cancer Surgery Through a Statewide Quality Collaborative.

Persistent racial disparities in lung cancer incidence, treatment, and survival are well documented. Given the importance of surgical resection for lung cancer treatment, racial disparities in surgical quality were investigated using a statewide quality collaborative. This retrospective study used data from the Michigan Society of Cardiothoracic Surgeons General Thoracic database, which includes data gathered for the Society of Thoracic Surgeons General Thoracic Surgery Database at 17 institutions in Michigan. Adult patients undergoing resection for lung cancer between 2015 and 2021 were included. Propensity score-weighting methodology was used to assess differences insurgical quality, including extent of resection, adequate lymph node evaluation, 30-day mortality, and 30-day readmission rate between white and black patients. The cohort included 5073 patients comprising 357 (7%) black and 4716 (93%) white patients. The black patients had significantly higher unadjusted rates of wedge resection than the white patients, but after propensity score-weighting for clinical factors, wedge resection did not differ from lobectomy (odds ratio [OR], 1.07; 95% confidence interval [CI], 0.78-1.49; P = 0.67). The black patients had fewer lymph nodes collected (incidence rate ratio [IRR], 0.77; 95% CI, 0.73-0.81; P < 0.0001) and lymph node stations sampled (IRR, 0.89; 95% CI, 0.84-0.94; P < 0.0001). The black patients did not differ from the white patients in terms of mortality (OR, 0.65; 95% CI, 0.19-2.34; P = 0.55) or readmission (OR, 0.79; 95 % CI, 0.49-1.27; P = 0.32). The black patients had longer hospital stays (OR, 1.08; 95% CI, 1.02-1.14; P = 0.01). In a statewide quality collaborative that included high-volume centers, black patients received a less extensive lymph node evaluation, with fewer non-anatomic wedge resections performed, and a more limited lymph node evaluation with lobectomy.

Gender disparities in incidence and projections of lung cancer in China and the United States from 1978 to 2032: an age-period-cohort analysis.

Lung cancer incidences tend to be higher among males than females in both China and the United States, yet secular incidence patterns are different due to distinct population and environmental exposures. We examined long-term and future trends of lung cancer incidence, as well as the associations of age, period, and cohort effects with gender disparities. Using data from the Cancer Incidence in Five Continents from 1978 to 2012, we calculated age-standardized, age-specific incidence, and male-to-female incidence rate ratios (IRR), and conducted an age-period-cohort analysis. The average annual percentage change (AAPC) of the trends was obtained by Joinpoint Regression. Bayesian age-period-cohort analysis was also conducted to project incidences to 2032. In China, age-standardized incidence revealed a decreasing trend among males, but showed increasing trends among the younger age groups (30-54years) in females. Age-standardized incidence rates of males decreased but remained stable among females from 1972 to 2012 in the United States. Male-to-female incidence rate ratios narrowed in both countries and reversed among younger birth cohorts in the United States. Gender disparities are expected to continue to diminish in both countries, and incidence among females appears to exceed that of males in the United States by around 2023-2027. Gender disparities in lung cancer incidence persist and will continue into the future in both countries, but our findings suggested that smoking may play different roles in gender disparities in lung cancer incidence between the two countries. Further population-based epidemiological studies among females in China are imperative.

Evaluation of tumor gene expression profile (GEP) in minority patients with stage IV non-small cell lung cancer (NSCLC).

e21043 Background: Differences in tumor gene expression profile (GEP) may contribute to disparities in lung cancer incidence and survival between racial and ethnic groups. For patients with stage IV NSCLC, tumor biomarker analysis is important for identification of potentially effective targeted therapies. However, despite advancements in biomarker testing and targeted therapy, minority patient enrollment in clinical trials remains low and it has been shown that minority patients are less likely to undergo next-generation sequencing (NGS) compared to Non-Hispanic Whites (NHW). As such, frequencies of tumor biomarkers in minority populations in the United States are not well-defined. This study aimed to determine the extent of tumor GEP diversity in minority patients vs NHW. Methods: This retrospective study included 196 adult patients with stage IV NSCLC that had a baseline NGS of tumor tissue or blood (liquid biopsy) performed between July 1, 2015 and June 30, 2021. Minority populations included Hispanic, African American, and Asian patients. Data collected utilizing the electronic medical record included patient demographics, detection of tumor biomarkers and treatment initiated. Descriptive statistics were calculated for all demographic and clinical variables. Comparisons of actionable epidermal growth factor receptor (EGFR) mutation frequency between NHW and minority patients were done using Chi-squared and Fisher’s exact tests. Results: Of the 196 patients evaluated, baseline characteristics included 46% male, 67% former smokers, 54% NHW, 31% Hispanic, 9% African American, 5% Asian, and 1% other. The median age at diagnosis was 66 ± 12 years. Actionable mutations (EGFR, KRAS, BRAF, ROS-1, ALK, MET, NTRK 1-3) were found in 50% of patients (see Table). The frequency of actionable EGFR mutations was higher in minority patients overall compared to NHW (39.3% vs 21.5%; p &lt; 0.01). The frequency of actionable EGFR mutations was similar between NHW and Hispanic patients (21.5% vs 27.9%; p = 0.35), however differences were observed comparing NHW to African American (21.5% vs 50%; p = 0.02) and Asian (21.5% vs 90%; p &lt; 0.01) patients, respectively. Conclusions: Among patients with stage IV NSCLC, the GEP of minority patients varied from that of NHW. Asian patients had the highest frequency of EGFR mutations, followed by African American and Hispanic patients, respectively. Larger studies are needed to validate these findings.[Table: see text]

RNA splicing and aggregate gene expression differences in lung squamous cell carcinoma between patients of West African and European ancestry

ObjectivesDespite disparities in lung cancer incidence and mortality, the molecular landscape of lung cancer in patients of African ancestry remains underexplored, and race-related differences in RNA splicing remain unexplored. Materials and methodsWe identified differentially spliced genes (DSGs) and differentially expressed genes (DEGs) in biobanked lung squamous cell carcinoma (LUSC) between patients of West African and European ancestry, using ancestral genotyping and Affymetrix Clariom D array. DSGs and DEGs were validated independently using the National Cancer Institute Genomic Data Commons. Associated biological processes, overlapping canonical pathways, enriched gene sets, and cancer relevance were identified using Gene Ontology Consortium, Ingenuity Pathway Analysis, Gene Set Enrichment Analysis, and CancerMine, respectively. Association with LUSC survival was conducted using The Cancer Genome Atlas. Results4,829 DSGs and 267 DEGs were identified, including novel targets in NSCLC as well as genes identified previously to have relevance to NSCLC. RNA splicing events within 3 DSGs as well as 1 DEG were validated in the independent cohort. 853 DSGs and 29 DEGs have been implicated as potential drivers, oncogenes and/or tumor suppressor genes. Biological processes enriched among DSGs and DEGs included metabolic process, biological regulation, and multicellular organismal process and, among DSGs, ion transport. Overlapping canonical pathways among DSGs included neuronal signaling pathways and, among DEGs, cell metabolism involving biosynthesis. Gene sets enriched among DSGs included KRAS Signaling, UV Response, E2 F Targets, Glycolysis, and Coagulation. 355 RNA splicing events within DSGs and 18 DEGs show potential association with LUSC patient survival. ConclusionThese DSGs and DEGs, which show potential biological and clinical relevance, could have the ability to drive novel biomarker and therapeutic development to mitigate LUSC disparities.

Assessing Disparities in Lung Cancer Incidence for Gender Minority Individuals Using California Cancer Registry Data

Gender minority individuals (GMIs) face unique challenges in cancer diagnosis and care.1,2 Disproportionate burden of lung cancer is expected among GMIs because of their high smoking rate and known disparities in cancer screening.3 However, population-based cancer registry data have not been fully used in assessing the cancer disparities among GMIs,1 even though population-based cancer registries do collect sex information beyond male and female.4 We found one previous study using national cancer surveillance data that identified lung cancer as the most common cancer for transgender indivduals.

Recurrent PTPRT/JAK2 mutations in lung adenocarcinoma among African Americans

Reducing or eliminating persistent disparities in lung cancer incidence and survival has been challenging because our current understanding of lung cancer biology is derived primarily from populations of European descent. Here we show results from a targeted sequencing panel using NCI-MD Case Control Study patient samples and reveal a significantly higher prevalence of PTPRT and JAK2 mutations in lung adenocarcinomas among African Americans compared with European Americans. This increase in mutation frequency was validated with independent WES data from the NCI-MD Case Control Study and TCGA. We find that patients carrying these mutations have a concomitant increase in IL-6/STAT3 signaling and miR-21 expression. Together, these findings suggest the identification of these potentially actionable mutations could have clinical significance for targeted therapy and the enrollment of minority populations in clinical trials.

Racial disparities in lung cancer incidence and mortality over the last two decades; a Population-Based Study

Abstract Background Racial disparities in the incidence and survival of lung cancer patients have been thoroughly studied. However, large epidemiologic studies evaluating temporal trends based on race are not prevalent. In this study, we aim to evaluate trends of incidence and mortality of lung cancer patients with a focus on patients of Asian origins. Methods We used SEER 18 database to study lung cancer cases in the US during 2000-2015. Incidence and mortality rates of lung cancer were calculated by race and were expressed by 100,000 person-years. Annual percent change (APC) was calculated using joinpoint regression software. All statistical tests were two-sided. Results 794,319 patients with lung cancer were identified. Most patients were whites (83.32%), followed by blacks (10.85%), Asians (5.37%), and American Indians (4.68%), with incidence rates of 60.86, 67.538, 37.325, and 32.195 per 100,000 person-years, respectively. Incidence rates of lung cancer decreased significantly among Asians during the study period, with this decrease being more prominent since 2012 (APC=-3.148%, p-value= 0.018). Similar trends were observed in other races. Mortality due to lung cancer was 49.001, 56.245, 28.916, and 27.980 per 100,000 person-years in whites, blacks, Asians, and American Indians, respectively. Mortality rates of both Asians increased significantly from 2000-2009 (APC=2.429%, P Conclusion Patients of Asian origins have shown lower incidence and mortality rates of lung cancer when compared to whites or blacks. Despite the declining incidence of lung cancer in Asians, mortality was inclining early 2000s yet started to decline since 2013. Understanding the root causes of the earlier incline and later decline can help improve survival in Asian lung cancer patients and lead to a further decline in mortality rates in the near future.

Abstract IA02: Genetic, environmental, and biological contributions to racial disparities in lung cancer incidence

Abstract Lung cancer is the leading cause of cancer-related deaths in the United States (1). In addition, there are significant disparities in lung cancer across populations. Compared with European Americans, African Americans are disproportionally affected by lung cancer, both in terms of incidence and survival (2,3). Lung adenocarcinoma among African Americans is 1.30 (1.10 - 1.90) times higher compared with European Americans; squamous cell carcinoma 1.80 (95% C.I. 1.1 - 2.3) times higher (4). There are also differences in lung cancer outcomes between European Americans and African Americans (2,5), some of which may be due to differences in cell biology between these two populations. However, studies have generally shown that differences in access to care may explain most of the variance in survival times (5-7). In addition, the gains in survival over the past 20 years among lung cancer patients have been similar in both European Americans and African Americans. Thus, the causal factors – genetic, environmental or otherwise – that lead to a greater incidence of lung cancer in African Americans are largely unknown. Smoking is the strongest risk factor for lung cancer development. However, several studies suggest that smoking prevalence and behaviors do not fully explain the disparity in lung cancer incidence. For example, African Americans have a lower smoking prevalence than European Americans and only 5.8% of African Americans are heavy smokers, compared with 19.2% of European Americans (8). In fact, when one compares smoking rates across ethnic groups matched for equal levels of smoking, African Americans still experience a higher burden of lung cancer incidence (8) - although this is attenuated with higher numbers of cigarettes smoked per day. This has led some to suggest that African Americans are more susceptible to the carcinogenic effects of tobacco at lower doses. However, this has not been empirically tested. It is possible that there are differences in nicotine and tobacco carcinogen metabolism between European Americans and European Americans that could account for the differences in cancer incidence between. On average, 72% of nicotine is converted to cotinine, the primary proximate metabolite of nicotine (9). Racial and ethnic differences in urinary (10,11) and blood cotinine (11-13) concentration per cigarette smoked have been well established. In addition, studies have found that levels of NNK metabolites (11,14) and thiocyanate (11) are higher in African Americans compared with European Americans. However, no clear genes or pathways have yet been identified that explain the disparity. And, given the strong relationship between smoking and lung cancer, it is hard to completely discount smoking as a cause of incidence disparities (8). Other risk factors to explain higher lung cancer incidence among African Americans include genetics, SES, smoking, BMI, and/or alcohol consumption. Recent studies show that the same loci associated with risk of lung cancer in European American smokers, i.e., chr15q25, are also associated with lung cancer in African Americans (15-18). Disparities in lung cancer incidence could be driven by the environment. For example, a recent study found that African Americans were more likely to reside in areas with the highest levels of air toxin exposure (19). Studies of breast and prostate cancer (20,21) have shown that whatever the cause of cancer health disparities, the consequences of these disparities manifest themselves as differences in the molecular and cell biology of the cancer. In lung cancer, we have explored the biological differences between lung cancer in European Americans and African Americans. These studies show that while some of the perturbed pathways in lung cancer remain the same for European Americans and African Americans, there are specific differences distinct to African Americans. Continued research efforts in the field are needed to determine the contribution of smoking, and indeed other factors, to lung cancer disparities. This work needs to be complemented with research that dissects the consequences of these disparities and the translation of these discoveries into improved patient care.

Racial/Ethnic Variations in Lung Cancer Incidence and Mortality, Adjusted for Smoking Behavior: Results From the Women's Health Initiative: Outcomes/Health Services Research

1528 Background: It is unclear whether there are racial/ethnic disparities in lung cancer incidence and mortality among women. Therefore, we examined lung cancer incidence and mortality in the Women’s Health Initiative (WHI), a prospective cohort of post-menopausal women. Methods: Lung cancer diagnoses were centrally adjudicated by pathology review. Logistic regression models estimated odds of incidence and mortality by race/ethnicity adjusted for age, education, calcium/vitamin D, BMI, smoking (status, age at start, duration and pack-years), alcohol, family history, oral contraceptive, hormones, physical activity, and diet. Results: The analytic cohort included 129,951 women -108,487 (83%) white (47.5% current/ past smoker); 10,892 (8%) Black (47.7% current/ past smoker); 4,882 (4%) Hispanic (33.7% current/past smoker); 3,696 (3%) Asian/Pacific Islander (A/PI) (26.2 % current/past smoker); 534 American Indian/Alaskan Native (48.3% current/past smoker) and 1994 (1.4%) other (41.6% current/past smoker). In...

Opportunities to address lung cancer disparities among African Americans.

Race and socioeconomic status are well known to influence lung cancer incidence and mortality patterns in the U.S. Lung cancer incidence and mortality rates are higher among blacks than whites. In this article we review opportunities to address disparities in lung cancer incidence, mortality, and survivorship among African Americans. First, we summarize recent advances in the early detection and treatment of lung cancer. Then we consider black-white disparities in lung cancer treatment including factors that may contribute to such disparities; the literature on smoking cessation interventions for patients with or without a lung cancer diagnosis; and the important roles played by cultural competency, patient trust in their physician, and health literacy in addressing lung cancer disparities, including the need for culturally competent lung cancer patient navigators. Intervention efforts should focus on providing appropriate quality treatment for lung cancer and educating African Americans about the value of having these treatments in order to reduce these disparities. Culturally competent, patient navigation programs are needed that support lung cancer patients, especially socioeconomically disadvantaged patients, from the point of diagnosis to the initiation and completion of treatment, including cancer staging.

A prospective study of plasma Selenoprotein P and lung cancer risk among low-income adults.

Epidemiologic studies have shown increased risks of lung cancer among adults with low blood levels of selenium, although evidence is inconsistent. In the United States, the incidence of lung cancer is higher and mean serum selenium levels lower among Blacks than Whites, but prior studies have not assessed the selenium-lung cancer association among Blacks. From the prospective Southern Community Cohort Study, we identified 372 participants who provided blood samples and subsequently developed lung cancer. Selenoprotein P (SEPP1), the most abundant selenoprotein in plasma and a biomarker of selenium nutriture, was measured in the plasma from these individuals and from 716 matched controls. Mean SEPP1 levels were significantly (P < 0.0001) lower among Blacks than Whites. Conditional logistic regression models accounting for smoking revealed a significant trend of increasing OR of lung cancer with decreasing SEPP1 tertiles among Blacks (P = 0.0006) but not Whites (P = 0.69; Pinteraction = 0.10). The ORs and corresponding 95% confidence intervals of lung cancer risk among those with lowest versus highest tertile levels of SEPP1 were 2.4 (1.5-3.0) among Blacks and 1.1 (0.6-2.1) among Whites. Among a mostly low-income population in the southeastern United States, lower levels of SEPP1 were associated with an increasing risk of lung cancer among Blacks but not Whites. The combined findings of higher prevalence of low selenium status and higher lung cancer risk associated with low status raise the possibility that selenium deficiency may contribute to observed racial disparities in lung cancer incidence.

Racial/ethnic variations in lung cancer incidence and mortality, adjusted for smoking behavior: Results from the Women's Health Initiative.

1528 Background: It is unclear whether there are racial/ethnic disparities in lung cancer incidence and mortality among women. Therefore, we examined lung cancer incidence and mortality in the Women’s Health Initiative (WHI), a prospective cohort of post-menopausal women. Methods: Lung cancer diagnoses were centrally adjudicated by pathology review. Logistic regression models estimated odds of incidence and mortality by race/ethnicity adjusted for age, education, calcium/vitamin D, BMI, smoking (status, age at start, duration and pack-years), alcohol, family history, oral contraceptive, hormones, physical activity, and diet. Results: The analytic cohort included 129,951 women -108,487 (83%) white (47.5% current/ past smoker); 10,892 (8%) Black (47.7% current/ past smoker); 4,882 (4%) Hispanic (33.7% current/past smoker); 3,696 (3%) Asian/Pacific Islander (A/PI) (26.2 % current/past smoker); 534 American Indian/Alaskan Native (48.3% current/past smoker) and 1994 (1.4%) other (41.6% current/past smoker). In...

Role of Selected Genetic Variants in Lung Cancer Risk in African Americans

Black/white disparities in lung cancer incidence and mortality mandate an evaluation of underlying biological differences. We have previously shown higher risks of lung cancer associated with prior emphysema in African American compared with white patients with lung cancer. We therefore evaluated a panel of 1440 inflammatory gene variants in a two-phase analysis (discovery and replication), added top genome-wide association studies (GWAS) lung cancer hits from white populations, and 28 single-nucleotide polymorphisms (SNPs) from a published gene panel. The discovery set (477 self-designated African Americans cases, 366 controls matched on age, ethnicity, and gender) were from Houston, Texas. The external replication set (330 cases and 342 controls) was from the EXHALE study at Wayne State University. In discovery, 154 inflammation SNPs were significant (p < 0.05) on univariate analysis, as was one of the gene panel SNPs (rs308738 in REV1, p = 0.0013), and three GWAS hits, rs16969968 p = 0.0014 and rs10519203 p = 0.0003 in the 15q locus and rs2736100, in the HTERT locus, p = 0.0002. One inflammation SNP, rs950286, was successfully replicated with a concordant odds ratio of 1.46 (1.14-1.87) in discovery, 1.37 (1.05-1.77) in replication, and a combined odds ratio of 1.40 (1.17-1.68). This SNP is intergenic between IRF4 and EXOC2 genes. We also constructed and validated epidemiologic and extended risk prediction models. The area under the curve (AUC) for the epidemiologic discovery model was 0.77 and 0.80 for the extended model. For the combined datasets, the AUC values were 0.75 and 0.76, respectively. As has been reported for other cancer sites and populations, incorporating top genetic hits into risk prediction models, provides little improvement in model performance and no clinical relevance.

Racial and regional disparities in lung cancer incidence.

Lung cancer is the second most commonly diagnosed cancer and the leading cause of cancer-related death in the United States (US). We examined data from 2004 to 2006 for lung cancer incidence rates by demographics, including race and geographic region, to identify potential health disparities. Data from cancer registries affiliated with the Centers for Disease Control and Prevention's (CDC) National Program of Cancer Registries (NPCR), and the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results Program (SEER) were used for this study; representing 100% of the US population. Age-adjusted incidence rates and 95% confidence intervals for demographic (age, sex, race, ethnicity, and US Census region), and tumor (stage, grade, and histology) characteristics were calculated. During 2004 to 2006, 623,388 people (overall rate of 68.9 per 100,000) were diagnosed with lung cancer in the US. Lung cancer incidence rates were highest among men (86.2), Blacks (73.0), persons aged 70 to 79 years (431.1), and those living in the South (74.7). Among Whites, the highest lung cancer incidence rate was in the South (75.6); the highest rates among Blacks (88.9) and American Indians/Alaska Natives (65.4) in the Midwest, Asians/Pacific Islanders in the West (40.0), and Hispanics in the Northeast (40.3). Our findings of racial, ethnic, and regional disparities in lung cancer incidence suggest a need for the development and implementation of more effective culturally specific preventive and treatment strategies that will ultimately reduce the disproportionate burden of lung cancer in the US.

African Americans' responses to genetic explanations of lung cancer disparities and their willingness to participate in clinical genetics research

PurposeTo assess whether reactions to genetic explanations for disparities in lung cancer incidence among family members of African American patients with lung cancer are associated with willingness to participate in clinical genetics research. MethodsData are reported for 67 self-identified African Americans aged 18 to 55 years who completed a telephone survey assessing reactions to explanations (i.e., genetics, toxin exposure, menthol cigarettes, and race-related stress) for lung cancer disparities. Majority were female (70%), current smokers (57%), and patients' biological relatives (70%). ResultsFamily members rated the four explanations similarly, each as believable, fair, and not too worrisome. Participants also indicated a high level of willingness to participate in genetics research (M = 4.1 ± 1.0; scale: 1-5). Endorsements of genetics explanations for disparities as believable and fair, and toxin exposure as believable were associated significantly with willingness to participate in genetics research. ConclusionThese results suggest that strategies to encourage African Americans' participation in genetics research would do well to inform potential participants of how their involvement might be used to better understand important environmental factors that affect health disparities.