Illinois State Cancer Registry Research Articles

A geographic information system-based method for estimating cancer rates in non-censusdefined geographical areas.

To address locally relevant cancer-related health issues, health departments frequently need data beyond that contained in standard census area-based statistics. We describe a geographic information system-based method for calculating age-standardized cancer incidence rates in non-censusdefined geographical areas using publically available data. Aggregated records of cancer cases diagnosed from 2009 through 2013 in each of Chicago's 77 census-defined community areas were obtained from the Illinois State Cancer Registry. Areal interpolation through dasymetric mapping of census blocks was used to redistribute populations and case counts from community areas to Chicago's 50 politically defined aldermanic wards, and ward-level age-standardized 5-year cumulative incidence rates were calculated. Potential errors in redistributing populations between geographies were limited to <1.5% of the total population, and agreement between our ward population estimates and those from a frequently cited reference set of estimates was high (Pearson correlation r=0.99, mean difference=-4 persons). A map overlay of safety-net primary care clinic locations and ward-level incidence rates for advanced-staged cancers revealed potential pathways for prevention. Areal interpolation through dasymetric mapping can estimate cancer rates in non-census defined geographies. This can address gaps in local cancer-related health data, inform health resource advocacy, and guide community-centered cancer prevention and control.

Kidney Cancer in Rural Illinois: Lower Incidence Yet Higher Mortality Rates

To determine if rural status was associated with kidney and renal pelvis cancer (KCa) incidence and mortality in Illinois while controlling for known KCa risk factors and access to care variables. Age-adjusted KCa incidence rates from 1991 to 2010 were calculated from Illinois State Cancer Registry data. Age-adjusted KCa mortality rates were obtained from health statistics embedded within SEER*Stat. Rural Urban Continuum Codes designated Illinois' 102 counties as urban, rural adjacent to, and rural non-adjacent to a metropolitan area. County-level demographics and physician density were obtained from the Area Health Resource File. Behavioral Risk Factor Surveillance System data were used for smoking, obesity, and hypertension prevalence. Analysis of variance, correlation, and regression analyses were used. The incidence of KCa was found to be higher among urban compared to rural counties after controlling for known risk factors (P < .01). A larger proportion of cases were diagnosed at a localized stage in urban counties (<0.01). Mortality rates were significantly higher in rural counties (P = .02). The final regression model found rural status, higher incidence rate, fewer with localized stage at diagnosis, and lower urologist density to be variables significantly associated with higher KCa mortality. KCa incidence was higher in urban counties whereas mortality was higher in rural counties. The higher number of KCa cases diagnosed at a localized stage in urban counties and lower urologist density in rural counties suggest that poorer access to care may contribute to higher KCa mortality in rural Illinois. Telemedicine may be an opportunity to improve this disparity.

Arsenic in drinking water and prostate cancer in Illinois counties: An ecologic study

BackgroundInorganic arsenic is a lung, bladder, and skin carcinogen. One of the major sources of exposure to arsenic is through naturally contaminated drinking water. While positive associations have been observed between arsenic in drinking water and prostate cancer, few studies have explored this association in the United States. ObjectivesTo evaluate the association between inorganic arsenic concentrations in community water systems and prostate cancer incidence in Illinois using an ecologic study design. MethodsIllinois Environmental Protection Agency data on arsenic concentrations in drinking water from community water systems throughout the state were linked with county-level prostate cancer incidence data from 2007 to 2011 from the Illinois State Cancer Registry. Incidence rates were indirectly standardized by age to calculate standardized incidence ratios (SIRs) for each county. A Poisson regression model was used to model the association between county-level SIRs and mean arsenic tertile (0.33–0.72, 0.73–1.60, and 1.61–16.23ppb), adjusting for potential confounders. ResultsFor counties with mean arsenic levels in the second tertile, the SIR was 1.05 (95% CI: 0.96–1.16). For counties with mean arsenic levels in the third tertile, the SIR was 1.10 (95% CI: 1.03–1.19). There was a significant linear dose-response relationship observed between mean arsenic levels and prostate cancer incidence (p for trend=0.003). ConclusionsIn this ecologic study, counties with higher mean arsenic levels in community water systems had significantly higher prostate cancer incidence. Individual-level studies of prostate cancer incidence and low-level arsenic exposure are needed.

Abstract C43: Is the influence of high mammographic breast density on breast cancer incidence the same for non-Latina black and white women?

Abstract Background: Non-Latina Black (black) women, despite their lower BC incidence, are more likely to die from breast cancer compared to their nL White (white) counterparts. While differential access to care, comorbidities and BC aggressiveness are potential contributors to this difference, the potential impact of HMD on this disparity has rarely been explored. For example, nL black women are disproportionately diagnosed with more aggressive tumors that lack estrogen and progesterone receptors (ER and PR) and that are high grade. Therefore, if the association of HMD with breast cancer incidence varied by tumor subtype this could have implications for disparities in breast cancer aggressiveness and subsequent outcomes. Most of the conclusions establishing high mammographic breast density (HMD) as a risk factor for increased breast cancer incidence are derived from studies conducted primarily in whites, which jeopardizes generalizability. We sought to estimate the association between HMD and breast cancer incidence separately for white and black women and by tumor subtype, using data from a single, large healthcare organization. Methods: We used data from screening mammograms performed in women ages 18-100, between 2001 and 2010, probabilistically linked to incident BC cases recorded in the Illinois State Cancer Registry (ISCR) during 2001-2011. Each screening mammogram received a breast density score from the interpreting radiologist using the American College of Radiology Breast Imaging Reporting and Data System (BIRADS 1-4), defined as fatty (BIRADS 1), scattered fibroglandular (BIRADS 2), heterogeneously dense (BIRADS 3) or extremely dense (BIRADS 4). A mean BIRADS breast density score was calculated using available scores from both breasts at each exam. The mean was dichotomized as high (mean BIRADS score &amp;gt; 2.5) versus low (mean BIRADS score ≤2.5) and the dichotomous variable was modeled in logistic regression with generalized estimating equations (to account for multiple screens per woman) to estimate the association between breast density and the probability of a breast cancer diagnosis within 12 months of the screen. Models included age, race, family history, parity and exam year as covariates, and separate models were estimated for black and white women. Odds ratios were interpreted as rate ratios (RR) due to the rarity of the outcome (&amp;lt;1%). Model-based standardization (predictive margins) was use to estimate adjusted rate differences from the logistic regression models. Results: Included in this analysis were 616,466 screens on 201,348 white or black women during 2001-2010, and 4,104 BC in 3,706 women during 2001-2011 (overall rate of 6.7 per 1000 screens, 6.7 for whites and 6.5 for blacks, p=0.21). There were disparities in the distribution of tumor subtypes: breast cancers diagnosed in black women were more likely to be ER negative (23% vs. 15%, p&amp;lt;0.0001) and high grade (38% vs. 30%, p&amp;lt;0.0001) when compared to white women. Upon adjustment for age, family history, parity and exam year, HMD was associated with increased breast cancer incidence overall (RR=1.24, 95% CI: 1.16, 1.32, equivalent to an adjusted Rate Difference of 1.4 per 1000 screens). The association between HMD and breast cancer incidence was similar for whites (RR=1.26, 95% CI: 1.16, 1.36) and blacks (RR=1.19, 95% CI: 1.05, 1.34) and similar for ER positive (RR=1.23, 95% CI: 1.15, 1.31) and ER negative breast cancer (RR=1.29, 95% CI: 1.16, 1.45). HMD was modestly associated with incidence of low grade (RR=1.26, 95% CI: 1.12, 1.41), and moderate grade (RR=1.18, 95% CI: 1.08, 1.29) tumors, but more strongly associated with incidence of high grade tumors (RR=1.45, 95% CI: 1.30, 1.61). These RRs translated into adjusted Rate Differences of 0.4, 0.4 and 0.8 breast cancers per 1000 screens, respectively. Discussion: Our findings reiterate high breast density as a risk factor for breast cancer incidence. In addition, we found that the association was of roughly equal magnitude among white and black women, and of roughly equal magnitude for ER negative and ER positive tumors. The stronger association of HMD with high grade tumors, however, implies that HMD may be a more detrimental risk factor for black women who are more likely to experience higher grade tumors than white women. Citation Format: Katherine Y. Tossas-Milligan, Firas Dabbous, Garth Rauscher. Is the influence of high mammographic breast density on breast cancer incidence the same for non-Latina black and white women? [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr C43.

Abstract PR03: A reverse, racial disparity with respect to interval breast cancer rates within a large healthcare organization has implications for eliminating disparities more generally

Abstract Background: It is well established that Non Latina (nL) Black patients are more likely than nL white (white) patients to be diagnosed with more aggressive forms of breast cancer. In addition, prior population-based research conducted in Chicago suggests that black women tend to be screened at lower resource facilities, and may also have screening images of lower quality and be more likely to have their breast cancer missed at interpretation. Consistent with all of these observations, black patients were more likely to report symptomatic awareness of their breast cancer despite a recent asymptomatic screening mammogram in the Breast Cancer Care in Chicago study. Therefore, black women may be more likely than their white counterparts to have a breast cancer diagnosis following a negative screen (so-called interval breast cancer). METHODS: The goal of the present study was to examine potential disparities in interval breast cancer (IBC) using data from approximately 30 mammography sites (including 8 hospital-based sites) within a single large health care organization in metropolitan Chicago. Methods: A screening mammogram was defined as a bilateral mammogram with a description of screening in the radiology database, in women without a prior history of breast cancer, mastectomy, or breast implants, and without any imaging in the 9 months prior to the screen. We linked 761,908 screening examinations conducted between 2001-2010 to breast cancer incidence data from the Illinois state cancer registry, using probabilistic methods. After excluding other race/ethnicities for this analysis, we identified 4829 breast cancers diagnosed between 2001 and 2011 and within 12 months of a screen. An interval breast cancer was defined as a breast cancer diagnosed within 12 months of a negative screening mammogram (BIRADS 1,2). IBC was modeled in logistic regression with generalized estimating equations (to account for multiple screens per woman) while adjusting for age, parity, breast density, race, family history, parity and exam year, ER status, tumor grade, and individual screening facility as covariates. Of the 31 facilities with data, 18 smaller screening facilities with less than 20 associated breast cancer diagnoses were collapsed into a single category. Model-based standardization (predictive margins) was used to estimate adjusted prevalence differences (PDs) in IBC from the logistic regression models, and 95% bias-corrected bootstrap confidence intervals were obtained (1000 replications). Results: Before adjusting for mammography site, black patients were, contrary to expectation, less likely to experience an IBC than white patients (1.36 vs. 1.83 per 1000 screens, adjusted Rate Difference or RD = - 0.47 per 1000 screens, p&amp;lt;0.0001). The proportion of screening mammograms conducted in Black women ranged from 1% to 96% across mammography sites, and IBC rates ranged across facilities from 9 per 100 screens to 29 per 1000 screens (p&amp;lt;0.0001). After controlling for mammography site the reverse disparity in IBC disappeared and the IBC rate was negligibly higher in black than white patients (1.79 vs. 1.68 per 1000 screens, p=0.614). Conclusion: In this large healthcare organization, we observed a reverse disparity such that white patients were more likely than their black counterparts to experience an IBC, but the association disappeared when we took mammography site into account in the analysis. These results suggest that higher quality mammography screening resources are more widely accessible to black than white patients within this organization. Larger volume facilities within this organization tend to be located in urban areas with higher proportions of black women, whereas smaller standalone facilities tend to be located in the suburbs where there are a higher proportion of white women. These standalone facilities may be less likely to employ breast imaging specialists and less likely provide multimodality breast imaging in a multidisciplinary setting, and these differences may be contributing to differential access to quality screening that benefits black women. The larger implication of these findings is that at a population level, racial disparities in breast cancer could perhaps be ameliorated or even eliminated if resources were disproportionately made more available to black women. In order to overcome breast cancer disparities and create true equity in care, disproportionate resource allocation solutions may be necessary. This abstract is also presented as Poster C61. Citation Format: Garth H. Rauscher, Firas Dabbous, Terry Dolecek, Terry Macarol, Katherine Tossas-Milligan, Jenna Khan, Sarah Friedwald, Wm. Thomas Summerfelt. A reverse, racial disparity with respect to interval breast cancer rates within a large healthcare organization has implications for eliminating disparities more generally. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr PR03.

Abstract A52: Use of geographic information systems to identify geographic clustering of screening colonoscopy resources with the city of Chicago

Abstract Background: In Illinois for the year 2014, colorectal cancer (CRC) is projected to cause 2,190 deaths, making it the leading cause of non-tobacco related cancer mortality. African American Illinois residents have an approximately 7% greater incidence and a 30% higher mortality rate when compared to white residents. Guideline consistent routine screening is known to reduce death due to CRC. However, according to the Centers for Disease Control, Illinois currently ranks in the lowest quartile amongst states for up-to-date screening of adults age 50 to 75 years. Chicago's South Side includes 34 of the city's 77 recognized community areas and is home to a combined population of more than 800,000 residents, of whom greater than 75% are African American. The contiguous communities that make up the South Side cover approximately 60% of Chicago's land area. Relatively homogenous minority communities, such as Chicago's South Side, are prone to the development of healthcare inequities that may result in the development of healthcare disparities. Objective: The objectives of this study are to use geographic information systems (GIS) and spatial analysis techniques to investigate geographic variations in the distribution of colonoscopy sites within the City of Chicago. Methods: CRC incidence data (1986-2010) by Zip code was obtained from the Illinois State Cancer Registry. Population characteristics by ZIP code (sex, median age, total population, median household income, racial/ethnic makeup) were obtained from the 2010 Census and Demographic Profile. The locations of colonoscopy sites were identified through a combination of internet search; review of Gastroenterology organization membership rosters; and expert opinion. Colonoscopy site addresses were geocoded using GPS Visualizer. Mapping and testing for spatial autocorrelation (global and local) were performed using STATA 13. Results: 55 colonoscopy sites were identified within the City of Chicago. 15 of 55 (27%) colonoscopy sites were located within Chicago's South Side. The geocoded address of each colonoscopy site was mapped to assess resource distribution. Testing for local spatial autocorrelation of colonoscopy sites by ZIP code identified significant local autocorrelation centered at Zip code 60613 (Moran's Ii = 131.399, p = 0.046), located within Chicago's North Side. Testing for global autocorrelation using population characteristics and CRC incidence data by ZIP code revealed evidence of significant global autocorrelation for areas with increased median household income (Moran's I = 0.532, p &amp;lt; 0.001). Conclusions: There is unequal distribution of colonoscopy sites across the City of Chicago with 15 sites (27%) located on Chicago's South Side. Testing for local spatial autocorrelation was significant for clustering of colonoscopy sites near the Zip code 60613, located on Chicago's North Side. Significant global autocorrelation was found related to increasing median household income. The clustering of colonoscopy sites near ZIP codes with increased median household incomes represents a healthcare resource inequity that may lead to persistence of disparities in CRC screening among low-income, medically underserved, and/or minority communities. Citation Format: Keith B. Naylor, Karen E. Kim. Use of geographic information systems to identify geographic clustering of screening colonoscopy resources with the city of Chicago. [abstract]. In: Proceedings of the Seventh AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 9-12, 2014; San Antonio, TX. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2015;24(10 Suppl):Abstract nr A52.

Exploration of rural disparities in pancreatic cancer staging and mortality to incidence ratio in Illinois.

260 Background: Despite recent impetus towards regionalization of pancreatectomy to high-volume centers, rural disparities have not been explored for pancreas cancer outcomes. Analysis of the National Cancer Database showed less than one third of patients with resectable disease actually undergo surgery, suggesting opportunities for improvement in global systems related to pancreas cancer care, including appropriate referral for surgical resection. We intended to explore the impact of rurality and gastroenterologist (GI) density on staging and mortality for pancreas cancer. Methods: Age-adjusted pancreas cancer incidence and staging proportion were calculated for each county using 1991-2010 data from the Illinois State Cancer Registry. Age-adjusted mortality rates were calculated using SEER*STAT. Choropleth maps were created to illustrate Mortality-Incidence Ratios (MIRs) by Illinois county using ArcGIS. Mean GI density for each county was calculated from the US Area Health Resource File. USDA Economic Research Service rural-urban continuum codes (RUCC) and US census percent rurality data were used to designate county rurality and adjacency to metro counties. Chi-square, ANOVA, and Spearman’s rho calculations were performed. Results: A greater proportion of counties with high MIR were in Southern, more rural, Illinois. No GIs were located in 65 out of 102 Illinois counties (64%) during the time interval analyzed, with a mean density of 1.0 per 100,000. Counties without GIs were significantly more rural, poorer, and less educated than counties with GIs. Unstaged pancreas cancers were inversely correlated with GI density (Spearman’s rho=-0.20; p=0.04). MIR was positively correlated with percent rurality (Spearman’s rho=0.23; p=0.02). MIR was also predicted by RUCC category, and was significantly greater in rural regions not adjacent to metro counties (p=0.02). Conclusions: Higher rates of unstaged pancreas cancer and higher MIR were noted in rural regions, which may be influenced by the availability of gastroenterologists or other specialty services. Further exploration of the impact of distance from high-volume cancer centers on rural cancer outcomes is warranted.

Abstract B74: Examining racial/ethnic disparities in mammography screening performance in a single, large healthcare organization

Abstract Introduction: Screening mammography for early detection of breast cancer is subject to both false positive and false negative results. False positive mammograms subject women to unnecessary diagnostic imaging and biopsies that create a burden to the patient and costs to the health care system. False negative mammograms, on the other hand, result in the diagnosis of an “interval” cancer following symptoms and typically at a later stage than if discovered on the prior screen. Prior studies conducted in metropolitan Chicago suggested that differences in both mammogram image quality and quality of the interpretation of the mammogram might contribute to higher false negative rates (FNR) and higher false positive rates (FPR) for ethnic minority patients. We sought to examine predictors of FNR and FPR, and whether ethnic disparities might exist in these outcomes within a single, large healthcare organization. Methods: Screening mammograms during 2001-2009 were linked to incident breast cancer cases for the period 2001-2010 from the Illinois State Cancer Registry (ISCR) using probabilistic linkage methods. Screening mammograms were scored by the interpreting radiologist using the American College of Radiology Breast Imaging Reporting and Data System (BIRADS) and each mammogram was defined as negative (BIRADS 1,2) or positive (BIRADS 0,4,5); BIRADS 3 mammograms were excluded from these analyses. A false positive (FP) mammogram was defined as a screening mammogram with an abnormal interpretation which nonetheless did not result in a breast cancer diagnosis in the subsequent 12 months. A false negative (FN) mammogram was defined as a screening mammogram with a normal interpretation in a woman who nonetheless was diagnosed with breast cancer (“interval cancer”) in the subsequent 12 months. We examined patient factors (race/ethnicity, age at diagnosis, and breast density) and tumor characteristics including hormone (estrogen and progesterone) receptor (ER/PR) status, tumor grade, and behavior (in-situ vs. malignant) and their association with FNR and FPR. Results: A total of 669,222 screens were included in this analysis and 4,058 breast cancer cases were diagnosed in the 12 months subsequent to each screening mammogram (3,071 screen-detected and 988 interval cancers). Overall, the false negative rate was 24.3%. As expected, the FNR decreased with increasing age, and increased with increasing breast density. Also as expected, FNR was higher for ER-/PR- breast cancer than other forms (31% vs. 25%, p=0.01), was higher for high grade/undifferentiated tumors and was higher for malignant than in situ tumors (27% vs. 19%, p &amp;lt;0.001). Contrary to expectation, however, FNR was higher in White than African Americans patients (26% vs. 20%, p&amp;lt;0.001); and FNR was higher for digital than analog mammograms (27% vs. 23%, p=0.001). With regards to false positive rate (FPR), FPR was 12.6% overall. As hypothesized, FPR was slightly higher in African Americans compared to Whites (14% vs. 11%, p=0.014), and higher for mammograms performed on women with heterogeneously/extremely dense versus less dense breasts (14% vs. 11%, p&amp;lt;0.0001). Conclusion: Contrary to expectation, we did not find a racial disparity in the probability of a false negative mammogram, though we did find a modestly increased false positive rate in ethnic minorities. Radiologists in this organization are provided feedback on the quality of their screening interpretations on a regular basis, and this quality control program may be responsible for leveling the quality of screening mammography by race/ethnicity. Citation Format: Firas M. Dabbous, Garth Rauscher, Terry Macarol, Jenna Khan, Therese Dolecek, Sally Friedewald, Teena Francois, Tom Summerfelt. Examining racial/ethnic disparities in mammography screening performance in a single, large healthcare organization. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B74. doi:10.1158/1538-7755.DISP13-B74

Abstract A50: Is there a reverse racial/ethnic disparity in chemotherapy treatment among breast cancer patients?

Abstract Background: There is evidence that minority women are more likely than White women to receive suboptimal breast cancer care, however this may not be the case with regards to chemotherapy for which White women may be less likely than Black or Hispanic women to receive chemotherapy. In order to better understand this apparent reverse disparity, this study seeks to examine how changes in the treatment guidelines may affect the disparity observed in chemotherapy treatment. Methods: Interview and medical record data came from a population-based study of 989 breast cancer patients (397 non-Hispanic White, 411 non-Hispanic Black, 181 Hispanic) diagnosed between 2005-2008. Of these, 87% (N=849) consented to medical record abstraction, including a linkage with the Illinois State Cancer Registry (ISCR). Patients who consented to the medical record abstraction and had single primary tumors were considered for this study. Eligibility for chemotherapy (CT) was defined according to the National Comprehensive Cancer Network (NCCN) guidelines in two ways. First, CT eligibility was defined according to the 2005 guidelines and then also according to the 2006-2007 guidelines. The outcome variables included treatment recommendation, acceptance, and initiation which were derived from the interview, medical record, and ISCR data. Age-adjusted risk differences (RDs) were estimated using logistic regression (with marginal standardization) in order to report percentages. Results: The medical record consent rate was 87%. Among those with a medical record consent and single primary tumors (n=824), 460 were CT-eligible per the 2005 NCCN guidelines and 284 were CT-eligible per the 2006-2007 guidelines (eligibility could not be determined for 107 node-negative, hormone receptor-positive women because their HER2 status was unavailable). Using the 2005 NCCN guidelines, chemotherapy was recommended to 74% of CT-eligible patients and non-Hispanic White patients were less likely than minority patients to receive a recommendation (0.62 vs. 0.75, RD=13%p=0.001). However, if the 2006-2007 guidelines were used, 94% of eligible patients received a recommendation and there were no racial/ethnic differences. Of these women who received a recommendation, 98% accepted it and a resulting 100% initiated treatment. However, the overall treatment initiation was 92% and in multivariate analysis, patients with lower income (p=0.03), breast conserving surgery (p=0.01), and low grade tumors (p=0.05) were less likely to initiate chemotherapy. Conclusions: The apparent reverse racial/ethnic disparity in chemotherapy treatment may appear or disappear depending on which guideline is used to determine treatment eligibility. It is reasonable that clinicians change treatment practices ahead of published guidelines as to provide their patients with the best care. Future studies on treatment quality should consider this when defining treatment eligibility. The vast majority of CT-eligible patients are receiving chemotherapy, although patients with less aggressive appearing tumors are less likely to receive CT. Citation Format: Abigail Silva, Garth H. Rauscher, Kent Hoskins, Ruta D. Rao. Is there a reverse racial/ethnic disparity in chemotherapy treatment among breast cancer patients? [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr A50.

Abstract A49: Mediators of racial/ethnic disparities in radiation treatment among breast cancer patients.

Abstract Background: Radiation after surgery can reduce recurrence and breast cancer mortality yet there is some evidence that not all women receive guideline-concordant radiation treatment. Indeed, studies that have examined the receipt of radiation among women who underwent breast-conserving surgery have found that Black and Hispanic women were less likely than White women to complete their locoregional treatment. However, little is known about the factors that may facilitate or impede treatment. In order to better understand the causes of disparities in radiation treatment, this study seeks to: 1) determine the extent to which there is a racial/ethnic disparity in radiation treatment initiation, and 2) examine patient factors and hospital characteristics that may help explain the variation. Methods: Interview and medical record data came from a population-based study of 989 breast cancer patients (397 non-Hispanic White, 411 non-Hispanic Black, 181 Hispanic) diagnosed between 2005-2008. Of these, 87% (N=849) consented to medical record abstraction, including a linkage with the Illinois State Cancer Registry (ISCR). Patients who consented to the medical record abstraction and had single invasive primary tumors were considered for this study. Radiation treatment eligibility was defined according to the 2005-2007 National Comprehensive Cancer Network (NCCN) guidelines. The outcome variables included treatment recommendation, acceptance, and initiation which were derived from the interview, medical record, and ISCR data. Risk differences (RDs) were estimated using logistic regression (with marginal standardization). Potential mediators related to radiation initiation were identified, and then assessed by rescaling model coefficients using the method of Karlson, Holm, and Breen. All models were adjusted for age and time from diagnosis to interview. Results: Among patients with single invasive primary tumors (n=614), 443 patients (72%) were eligible for radiation treatment (RT) per the NCCN guidelines. Radiation treatment was recommended to 88% of eligible patients of which 93% accepted it. Among those who accepted treatment, 97% received radiation. This translated into an overall treatment initiation of 79%. Minority patients were less likely than non-Hispanic (nH) White patients to initiate radiation (0.75 vs. 0.85, RD=10%p=0.000). Minorities were more likely to have moderate-high grade tumors and symptomatically detected tumors which in turn were less likely to receive radiation (all p-values &amp;lt;0.01). Minority women were also more likely than nH White women (p&amp;lt;0.0001) to receive chemotherapy, which in turn was associated with lower receipt of RT (p&amp;lt;0.05). Together these factors explained 46% of the disparity (p=0.002). Conclusions: Patients who are eligible for radiation and have more aggressive appearing tumors at diagnosis are more likely to receive chemotherapy but at the expense of completing their locoregional (radiation) therapy. This disproportionately affects minority patients and results in underuse of radiation in these women. Greater diffusion of gene expression profiling (e.g. Oncotype) may improve cancer care not only by reducing overuse of chemotherapy but by eliminating chemotherapy as a potential barrier to receipt of RT. Citation Format: Abigail Silva, Garth H. Rauscher, Rao D. Ruta, Kent Hoskins. Mediators of racial/ethnic disparities in radiation treatment among breast cancer patients. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr A49.

Rural - urban inequalities in late-stage breast cancer: spatial and social dimensions of risk and access.

Rural - urban inequalities in health and access to health care have long been of concern in health-policy formulation. Understanding these inequalities is critically important in efforts to plan a more effective geographical distribution of public health resources and programs. Socially and ethnically diverse populations are likely to exhibit different rural - urban gradients in health and well-being because of their varying experiences of place environments, yet little is known about the interplay between social and spatial inequalities. Using data from the Illinois State Cancer Registry, we investigate rural - urban inequalities in late-stage breast cancer diagnosis both for the overall population and for African-Americans, and the impacts of socioeconomic deprivation and spatial access to health care. Changes over time are analyzed from 1988 - 92 to 1998 - 2002, periods of heightened breast cancer awareness and increased access to screening. In both time periods, the risk of late-stage diagnosis is highest among patients living in the most urbanized areas, an indication of urban disadvantage. Multilevel modeling results indicate that rural - urban inequalities in risk are associated with differences in the demographic characteristics of area populations and differences in the social and spatial characteristics of the places in which they live. For African-American breast cancer patients, the rural - urban gradient is reversed, with higher risks among patients living outside the city of Chicago, suggesting a distinct set of health-related risks and place experiences that inhibit early breast cancer detection. Findings emphasize the need for combining spatial and social targeting in locating cancer prevention and treatment programs.

Neighborhood Changes in Concentrated Immigration and Late Stage Breast Cancer Diagnosis

Immigrant women are at greater risk for late stage breast cancer diagnosis. The rapid increase in the US foreign-born population and new immigration patterns lead us to investigate the association between changes in immigrant population and the likelihood of distant metastasis stage at diagnosis of breast cancer among women in Cook County, Illinois. Analyses employed Illinois State Cancer Registry data for 42,714 breast cancer cases diagnosed between 1994 and 2003 in conjunction with 1990 and 2000 Census tract data. We find that concentration of and increases in immigrant populations within neighborhoods contributed to the risk of late stage breast cancer diagnosis. These findings suggest that, although some health indicators for immigrant populations have improved in recent years, important health disparities in breast cancer diagnosis still remain at the neighborhood level. They further suggest that cancer screening and follow-up resources should be directed to areas experiencing rapid increases in immigrant populations.

Rural reversal? Rural-urban disparities in late-stage cancer risk in Illinois.

Differences in late-stage cancer risk between urban and rural residents are a key component of cancer disparities. Using data from the Illinois State Cancer Registry from 1998 through 2002, the authors investigated the rural-urban gradient in late-stage cancer risk for 4 major types of cancer: breast, colorectal, lung, and prostate. Multilevel modeling was used to evaluate the role of population composition and area-based contextual factors in accounting for rural-urban variation. Instead of a simple binary rural-urban classification, a finer grained classification was used that differentiated the densely populated City of Chicago from its suburbs and from smaller metropolitan areas, large towns, and rural settings. For all 4 cancers, the risk was highest in the most highly urbanized area and decreased as rurality increases, following a J-shaped progression that included a small upturn in risk in the most isolated rural areas. For some cancers, these geographic disparities were associated with differences in population age and race; for others, the disparities remained after controlling for differences in population composition, zip code socioeconomic characteristics, and spatial access to healthcare. The observed pattern of urban disadvantage emphasized the need for more extensive urban-based cancer screening and education programs.

Characteristics of Mammography Facility Locations and Stage of Breast Cancer at Diagnosis in Chicago

In the United States, despite substantial investment in public health initiatives to promote early detection of breast cancer through screening mammography, the proportion of female breast cancers that have advanced beyond the localized stage by the time of diagnosis remains high. Our objective in this exploratory study was to investigate whether stage of breast cancer at diagnosis among Chicago residents is associated with characteristics of the neighborhoods in which proximate mammography facilities are located. Those characteristics may influence likelihood of utilizing the service routinely and partly explain differences in stage at diagnosis. We used a retrospective cohort design and combined 3 years of data from the Illinois State Cancer Registry (ISCR) with information on locations of mammography facilities, public transportation service, crime, and area demographic and economic characteristics. Using a Geographic Information System (GIS), we identified the five facilities located nearest to each case's residence. Estimates of the association between characteristics of mammography facility locations and breast cancer stage at diagnosis were obtained using the partial proportional odds regression model. We found that the number of homicides in areas in which the nearest mammography facilities were located was associated with increased odds of later stage diagnosis. This effect was independent of age, race, and residential area education and income. We found no effect on stage of distance, public transportation service, or measures of neighborhood social similarity. The "spatial dynamics" of health may involve geographies beyond the immediate neighborhood. The results of our study suggest that areas in which the nearest mammography facilities are located may be one such geography. We hope that this study will spark research interest in the impact of health service locations on utilization.

Elevated Rates of Neuroblastoma Associated with Exposure to Coal Tar from a Former Manufactured Gas Plant (MGP) Site

Purpose Extensive coal tar-related contamination from a former MGP site occurred in Taylorville, Illinois, including extremely high levels of polynuclear aromatic hydrocarbons, volatile organic compounds, and inorganic compounds in multiple on- and off-site environmental media. Coal tar has been classified as a known human carcinogen by numerous scientific and governmental panels of experts. Community concerns were raised regarding neuroblastoma risk given the proximity of a large, open pit with coal tar to the town playground, and known heightened fetal nervous system sensitivity to carcinogens. Methods A Standardized Incidence Ratio (SIR) analysis for the period 1986-1991 was conducted, comparing Taylorville and Christian County, IL with four comparison groups: 1) demographically-similar zip codes and counties; 2) demographically-similar zip codes without MGP sites; 3) the state of Illinois; and 4) the entire U.S. Confounding variables were accounted for by stratification or indirect adjustment. Disturbance and remediation of the site exacerbated the release of contaminants. Incident case data for the state of Illinois was obtained from the Illinois State Cancer Registry; population data was obtained from the 1990 U.S Census; and national reference rates were obtained from SEER. Results In all comparison groups, the SIR for neuroblastoma ranged from 9.9 to 24.3, with a lower-bounded 95% confidence interval (CI) that did not include 1. Comparisons using the four control groups provided comparable results, with higher SIRs generally seen in the comparison to the demographically similar, non-MGP site zip codes, which may imply an effect of the MGP sites on cancer incidence. Conclusion There was a significantly elevated incidence rate of neuroblastoma in children during a time period of heightened ambient exposure to coal tar-related contaminants relative to all comparison populations. There are 52,000 former MGP sites in the U.S. alone; thus, environmental exposure to coal tar is a continuing public health concern.

The black:white disparity in breast cancer mortality: the example of Chicago

The black:white disparity in breast cancer mortality has been increasing in the U.S. In order to gain insight into this disparity in Chicago, we examined mortality data together with other important measures associated with breast cancer. Trends in black:white female breast cancer mortality, incidence, stage at diagnosis, and mammography screening in Chicago were examined using data from the Illinois State Cancer Registry, Illinois Department of Public Health Vital Records, and the Illinois Behavioral Risk Factor Surveillance System. The breast cancer mortality rate for black women in Chicago for 1999-2003 was 49% higher than that of white women, but the disparity is a recent phenomenon that is increasing rapidly. In 2003 the black rate was 68% higher than the white rate. Mortality rates were similar in the 1980's and only started to diverge in the 1990's as a result of a sharp improvement in mortality among white women contrasted with no improvement for black women. This lack of progress for black women is perplexing given that self-reported mammography screening rates have been the same for blacks and whites in Chicago since at least 1996 and that the early detection of breast cancer for black women has been increasing. There has been no improvement in mortality from breast cancer for black women in Chicago in 23 years. This study, along with a review of the literature, lends support to the hypothesis that the disparities in breast cancer mortality are due to differential access to mammography, differential quality in mammography, and differential access to treatment for breast cancer. Fortunately, all three are amenable to intervention, which would help ameliorate this unacceptable disparity.

Cancer and benign tumor incidence among employees in a polymers research complex.

The detection of several intracranial tumors among employees in one building complex (C500) at a petrochemical research facility prompted investigation of a possible workplace cause. This retrospective follow-up study included 1847 subjects, of whom 1735 had worked in C500. Medical records, death certificates, and Illinois State Cancer Registry data confirmed self-reported cancers and tumors. Analyses compared the subjects' cancer and benign intracranial tumor incidence rates with national general population rates. C500 employees had 15% fewer than expected total cancers (92 observed/108 expected; standardized incidence ratio [SIR], 85; 95% confidence interval [95% CI], 69 to 104). An excess of brain cancer (6/2.0; SIR, 302; 95% CI, 111 to 657) was concentrated among white men who had 10 or more years since hire and 5 or more years of C500 employment (4/0.7; SIR, 602; 95% CI, 165 to 1552) and who had worked in a particular building of C500 (5/0.7; SIR, 735; 95% CI, 239 to 1716). An excess of benign intracranial tumors (6/1.6; SIR, 385; 95% CI, 142 to 839) was not restricted to a single type of tumor and was not concentrated in any particular building. Occupational exposure may have caused the increased rate of brain cancer but is a less likely explanation for the elevated rate of benign intracranial tumors.

Cancer incidence among employees at a petrochemical research facility.

This investigation evaluated cancer incidence among workers at a petrochemical research facility in Illinois. A cluster of brain cancer and other intracranial tumors had occurred at the facility before the study began. The subjects were 5641 people who had worked at the facility from 1970 through 1996 and who had lived in Illinois at any time between 1986 and 1997. Data on cancer cases came primarily from the Illinois State Cancer Registry. Analyses compared the 1986-to-1997 cancer incidence rates of employees with Illinois general population rates. Subjects had 18% fewer than expected total cancers (125 observed/153 expected cases; standardized incidence ratio [SIR], 82; 95% confidence interval [CI], 68 to 98), which was primarily attributed to a large deficit of lung cancer (10/26; SIR, 39; CI, 19 to 72). Brain cancer was increased in the overall study group (6/2.7; SIR, 222; CI, 81 to 484). This excess was restricted to white men who were scientists or technicians for one of the three companies at the facility (6/0.8; SIR, 750; CI, 275 to 1633); all cases in this group had worked in the "500 building complex" (6/0.6; SIR, 968; CI, 355 to 2106). Subjects also had an increased incidence of thyroid cancer (7/2.6; SIR, 265; CI, 106 to 546) that was not concentrated in particular occupational or building groups. The brain cancer incidence patterns indicated that an unidentified occupational exposure might have been responsible for the excess. Chance, socioeconomic factors leading to better case detection in facility employees than in the general population, and confounding by potential nonoccupational risk factors are plausible explanations of the observed increase in thyroid cancer.

Case-control studies of cancer in Illinois farmers using data from the Illinois State Cancer Registry and the U.S. Census of Agriculture

A series of case-control studies have been carried out to compare farmers reported to the Illinois State Cancer Registry (ISCR) with other males reported to the ISCR between 1986 and 1988. Data on the number of farms in each Illinois county producing given agricultural commodities were obtained from the United States Census of Agriculture and used as surrogate exposure indicators. Employment as a farmer was found to be associated with cancer of the eye [odds ratio (OR) = 6.49, 95% confidence interval (CI) = 1.78, 23.71], lip (OR = 4.42, 95% CI = 2.46, 7.94), prostate (OR = 1.15, 95% CI = 0.99, 1.35) and leukaemia (OR = 1.51, 95% CI = 1.01, 2.25). Wheat and soybean production were found to be positively associated with leukaemia. Hay and beef production were found to be positively associated with cancer of the prostate.

Cancer in Illinois construction workers: A study

A series of case-control studies using subjects from the Illinois State Cancer Registry have been conducted. Logistic regression was used to control for age and history of tobacco and alcohol use. Construction workers were consistently found to be younger than other subjects and to have used alcohol and tobacco more often. Significant positive associations between cancer of the stomach and welding (odds ratio [OR] = 2.11, 95% confidence interval [CI] = 1.09, 4.09), lung cancer and employment in the construction industry (OR = 1.18, 95% CI = 1.02, 1.26), and lung cancer and welding (OR = 1.68, 95% CI = 1.03, 2.76) were found. Significant negative associations between cancer of the colon and welding (OR = .54, 95% CI = .29, 1.00), cancer of the prostate and employment in the construction industry (OR = .76, 95% CI = .65, .89), cancer of the prostate and plumbing (OR = .44, 95% CI = .38, .50), cancer of the prostate and metal working (OR = .43, 95% CI = .19, .93), and bladder cancer and employment as an electrician (OR = .60, 95% CI = .36, 1.00) suggests that construction workers did not consistently experience excesses of cancers known to be associated with tobacco use, and an overall excess of sites not known to be related to tobacco use may have occurred.