Prostate cancer incidence and tumor severity in Georgia: descriptive epidemiology, racial disparity, and geographic trends

Application of Geographic Information Systems (GIS) in the Study of Prostate Cancer Disparities: A Systematic Review

Introduction: PCa is one of the cancers that exhibits the widest disparity gaps. Geographical place of residence has been shown to be associated with healthcare access/utilization and PCa outcomes. Geographical Information Systems (GIS) are widely being utilized for PCa disparities research, however, inconsistencies in their application exist. This systematic review will summarize GIS application within PCa disparities research, highlight gaps in the literature, and propose alternative approaches. Methods: This paper followed the methods of the Cochrane Collaboration and the criteria set of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles published in peer-reviewed journals were searched through the PubMed, Embase, and Web of Science databases until December 2022. The main inclusion criteria were employing a GIS approach and examining a relationship between geographical components and PCa disparities. The main exclusion criteria were studies conducted outside the US and those that were not published in English. Results: A total of 25 articles were included; 23 focused on PCa measures as outcomes: incidence, survival, and mortality, while only 2 examined PCa management. GIS application in PCa disparities research was grouped into three main categories: mapping, processing, and analysis. GIS mapping allowed for the visualization of quantitative, qualitative, and temporal trends of PCa factors. GIS processing was mainly used for geocoding and smoothing of PCa rates. GIS analysis mainly served to evaluate global spatial autocorrelation and distribution of PCa cases, while local cluster identification techniques were mainly employed to identify locations with poorer PCa outcomes, soliciting public health interventions. Discussion: Varied GIS applications and methodologies have been used in researching PCa disparities. Multiple geographical scales were adopted, leading to variations in associations and outcomes. Geocoding quality varied considerably, leading to less robust findings. Limitations in cluster-detection approaches were identified, especially when variations were captured using the Spatial Scan Statistic. GIS approaches utilized in other diseases might be applied within PCa disparities research for more accurate inferences. A novel approach for GIS research in PCa disparities could be focusing more on geospatial disparities in procedure utilization especially when it comes to PCa screening techniques. Conclusions: This systematic review summarized and described the current state and trend of GIS application in PCa disparities research. Although GIS is of crucial importance when it comes to PCa disparities research, future studies should rely on more robust GIS techniques, carefully select the geographical scale studied, and partner with GIS scientists for more accurate inferences. Such interdisciplinary approaches have the potential to bridge the gaps between GIS and cancer prevention and control to further advance cancer equity.

Geospatial analysis, web-based mapping and determinants of prostate cancer incidence in Georgia counties: evidence from the 2012-2016 SEER data

Background

Prostate cancer (CaP) cases are high in the United States. According to the American Cancer Society, there are an estimated number of 174,650 CaP new cases in 2019. The estimated number of deaths from CaP in 2019 is 31,620, making CaP the second leading cause of cancer deaths among American men with lung cancer been the first. Our goal is to estimate and map prostate cancer relative risk, with the ultimate goal of identifying counties at higher risk where interventions and further research can be targeted.

Methods

The 2012–2016 Surveillance, Epidemiology, and End Results (SEER) Program data was used in this study. Analyses were conducted on 159 Georgia counties. The outcome variable is incident prostate cancer. We employed a Bayesian geospatial model to investigate both measured and unmeasured spatial risk factors for prostate cancer. We visualised the risk of prostate cancer by mapping the predicted relative risk and exceedance probabilities. We finally developed interactive web-based maps to guide optimal policy formulation and intervention strategies.

Results

Number of persons above age 65 years and below poverty, higher median family income, number of foreign born and unemployed were risk factors independently associated with prostate cancer risk in the non-spatial model. Except for the number of foreign born, all these risk factors were also significant in the spatial model with the same direction of effects. Substantial geographical variations in prostate cancer incidence were found in the study. The predicted mean relative risk was 1.20 with a range of 0.53 to 2.92. Individuals residing in Towns, Clay, Union, Putnam, Quitman, and Greene counties were at increased risk of prostate cancer incidence while those residing in Chattahoochee were at the lowest risk of prostate cancer incidence.

Conclusion

Our results can be used as an effective tool in the identification of counties that require targeted interventions and further research by program managers and policy makers as part of an overall strategy in reducing the prostate cancer burden in Georgia State and the United States as a whole.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08254-0.

Regional trends in average years of potential life lost (AYPLL) secondary to prostate cancer deaths among Caucasians and African Americans treated by surgery or radiation

PURPOSE

To study regional trends in average years of potential life lost (AYPLL) among Caucasians (CA) and African Americans (AA) with prostate cancer (Pca) who received radical prostatectomy or radiation therapy among four different regions in the US as well as across different tumor grades. Years of potential life lost is defined as the difference between a predetermined end-point age and the age at death for a death that occurred prior to that end age, hence the AYPLL is calculated by dividing the total YPLL by the total number of patients died.

METHODS

The surveillance epidemiology and end results (SEER) database was used to identify Pca patients who were CA or AA and who have received radical prostatectomy or radiation therapy. Study duration was divided into four decades; 1973-1982 (D1), 1983-1992 (D2), 1993-2002 (D3), 2003-2012 (D4). Examined regions were; North East (NE), North central (NC), South and West. Tumor grade was classified into; well/moderately differentiated (WD/MD) and poorly/undifferentiated (PD/UD) groups. Differences in AYPLL among CA and AA in each of these variables were compared.

RESULTS

Overall, compared to CA, AA were diagnosed and died earlier from Pca. AA had higher AYPLL to Pca than CA. In both tumor grade groups, progressive increase in AYPLL among AA compared to CA was noted over the last three decades. In the WD/MD group, except for the South region, the highest recorded difference in AYPLL between AA and CA was in D4. In the PD/UD group, a similar difference in AYPLL between AA and CA was noted in all regions. The difference in AYPLL was higher in the PD/UD group than the WD/MD group.

CONCLUSIONS

Racial disparity between AA and CA existed across the examined regions. It is more pronounced in advanced tumor grades. The differences were more significant in the last decade.

Dysregulated gene expression predicts tumor aggressiveness in African-American prostate cancer patients

Molecular mechanisms underlying the health disparity of prostate cancer (PCa) have not been fully determined. In this study, we applied bioinformatic approach to identify and validate dysregulated genes associated with tumor aggressiveness in African American (AA) compared to Caucasian American (CA) men with PCa. We retrieved and analyzed microarray data from 619 PCa patients, 412 AA and 207 CA, and we validated these genes in tumor tissues and cell lines by Real-Time PCR, Western blot, immunocytochemistry (ICC) and immunohistochemistry (IHC) analyses. We identified 362 differentially expressed genes in AA men and involved in regulating signaling pathways associated with tumor aggressiveness. In PCa tissues and cells, NKX3.1, APPL2, TPD52, LTC4S, ALDH1A3 and AMD1 transcripts were significantly upregulated (p < 0.05) compared to normal cells. IHC confirmed the overexpression of TPD52 (p = 0.0098) and LTC4S (p < 0.0005) in AA compared to CA men. ICC and Western blot analyses additionally corroborated this observation in PCa cells. These findings suggest that dysregulation of transcripts in PCa may drive the disparity of PCa outcomes and provide new insights into development of new therapeutic agents against aggressive tumors. More studies are warranted to investigate the clinical significance of these dysregulated genes in promoting the oncogenic pathways in AA men.

Geographical Factors Associated with Health Disparities in Prostate Cancer

Background

Treatment variation in prostate cancer is common, and it is driven by clinical and clinician factors, patient preferences, availability of resources, and access to physicians and treating facilities. Most research on treatment disparities in men with prostate cancer has focused on race and socioeconomic factors. However, the geography of disparities — capturing racial and socioeconomic differences based on where patients live — can provide insight into barriers to care and help identify outlier areas in which access to care, health resources, or both are more pronounced.

Methods

Research regarding treatment patterns and disparities in prostate cancer using the Geographical Information System (GIS) was searched. Studies were limited to English-language articles and research focused on US populations. A total of 43 articles were found; of those, 30 provided information about or used spatial or geographical analyses to assess and describe differences or disparities in prostate cancer and its treatment. Two additional GIS resources were included.

Results

The research on geographical and spatial determinants of prostate cancer disparities was reviewed. We also examined geographical analyses at the state level, focusing on Florida. Overall, we described a geographical framework to disparities that affect men with prostate cancer and reviewed existing published evidence supporting the interplay of geographical factors and disparities in prostate cancer.

Conclusions

Disparities in prostate cancer are common and persistent, and notable differences in treatment are observable across racial and socioeconomic strata. Geographical analysis provides additional information about where disparate groups live and also helps to map access to care. This information can be used by public health officials, health-systems administrators, clinicians, and policymakers to better understand and respond to geographical barriers that contribute to disparities in care.

Investigation of Spatial Clustering of Biliary Tract Cancer Incidence in Osaka, Japan: Neighborhood Effect of a Printing Factory

BACKGROUND

In 2013, an unusually high incidence of biliary tract cancer among current or former workers of the offset color proof printing department of a printing company in Osaka, Japan, was reported. The purpose of this study was to examine whether distance from the printing factory was associated with incidence of biliary tract cancer and whether incident biliary tract cancer cases clustered around the printing factory in Osaka using population-based cancer registry data.

METHODS

We estimated the age-standardized incidence ratio of biliary tract cancer according to distance from this printing factory. We also searched for clusters of biliary tract cancer incidence using spatial scan statistics.

RESULTS

We did not observe statistically significantly high or low standardized incidence ratios for residents in each area categorized by distance from the printing factory for the entire sample or for either sex. The scan statistics did not show any statistically significant clustering of biliary tract cancer incidence anywhere in Osaka prefecture in 2004-2007.

CONCLUSIONS

There was no statistically significant clustering of biliary tract cancer incidence around the printing factory or in any other areas in Osaka, Japan, between 2004 and 2007. To date, even if some substances have diffused outside this source factory, they do not appear to have influenced the incidence of biliary tract cancer in neighboring residents.

Racial Disparities in Prostate Cancer Mortality in the 50 Largest US Cities

INTRODUCTION

This paper presents race-specific prostate cancer mortality rates and the corresponding disparities for the largest cities in the US over two decades.

METHODS

The 50 largest cities in the US were the units of analysis. Data from two 5-year periods were analyzed: 1990-1994 and 2005-2009. Numerator data were abstracted from national death files where the cause was malignant neoplasm of prostate (prostate cancer) (ICD9=185 and ICD10=C61). Population-based denominators were obtained from US Census data. To measure the racial disparity, we calculated non-Hispanic Black: non-Hispanic White rate ratios (RRs), rate differences (RDs), and corresponding confidence intervals for each 5-year period. We also calculated correlation and unadjusted regression coefficients for 11 city-level variables, such as segregation and median income, and the RDs.

RESULTS

At the final time point (2005-2009), the US and all 41 cities included in the analyses had a RR greater than 1 (indicating that the Black rate was higher than the White rate) (range=1.13 in Minneapolis to 3.24 in Los Angeles), 37 of them statistically significantly so. The US and 26 of the 41 cities saw an increase in the Black:White RR between the time points. The level of disparity within a city was associated with the degree of Black segregation.

CONCLUSION

This analysis revealed large disparities in Black:White prostate cancer mortality in the US and many of its largest cities over the past two decades. The data show considerable variation in the degree of disparity across cities, even among cities within the same state. This type of specific city-level data can be used to motivate public health professionals, government officials, cancer control agencies, and community-based organizations in cities with large or increasing disparities to demand more resources, focus research efforts, and implement effective policy and programmatic changes in order to combat this highly prevalent condition.

Lung Cancer Mortality and Topography: A Xuanwei Case Study

The epidemic of lung cancer in Xuanwei City, China, remains serious despite the reduction of the risk of indoor air pollution through citywide stove improvement. The main objective of this study was to characterize the influences of topography on the spatiotemporal variations of lung cancer mortality in Xuanwei during 1990-2013. Using the spatially empirical Bayes method, the smoothed mortality rate of lung cancer was obtained according to the mortality data and population data collected from the retrospective survey (1990-2005) and online registration data (2011-2013). Spatial variations of the village-level mortality rate and topographic factors, including the relief degree of land surface (RDLS) and dwelling conditions (VDC), were characterized through spatial autocorrelation and hotspot analysis. The relationship between topographic factors and the epidemic of lung cancer was explored using correlation analysis and geographically weighted regression (GWR). There is a pocket-like area (PLA) in Xuanwei, covering the clustered villages with lower RDLS and higher VDC. Although the villages with higher mortality rate (>80 per 10⁵) geographically expanded from the center to the northeast of Xuanwei during 1990-2013, the village-level mortality rate was spatially clustered, which yielded a persistent hotspot area in the upward part of the PLA. In particular, the epidemic of lung cancer was closely correlated with both RDLS and VDC at the village scale, and its spatial heterogeneity could be greatly explained by the village-level VDC in the GWR model. Spatiotemporally featured lung cancer mortality in Xuanwei was potentially influenced by topographic conditions at the village scale.

Prostate cancer incidence and agriculture practices in Georgia, 2000-2010

BACKGROUND

Georgia has prostate cancer incidence rates consistently above the national average. A notable portion of Georgia's economy is rooted in agricultural production, and agricultural practices have been associated with an increased risk of prostate cancer.

METHODS

Statistical analyses considered county age-adjusted prostate cancer incidence rates as the outcome of interest and three agricultural variables (farmland as percent of county land, dollars spent per county acre on agriculture chemicals, and dollars spent per county acre on commercial fertilizers) as exposures of interest. Multivariate linear regression models analyzed for each separately. Data were obtained from National Cancer Institute Surveillance, Epidemiology and End Results (SEER) 2000-2010, United States Department of Agriculture (USDA) 1987 Agriculture Survey, and 2010 US Census.

RESULTS

In counties with equal to or greater than Georgia counties' median percent African-American population (27%), dollars per acre spent on agriculture chemicals was significantly associated (P = 0.04) and dollars spent of commercial fertilizers was moderately associated (P = 0.07) with elevated prostate cancer incidence rates. There was no association between percent of county farmland and prostate cancer rates.

CONCLUSION

This study identified associations between prostate cancer incidence rates, agriculture chemical expenditure, and commercial fertilizer expenditure in Georgia counties with a population comprised of more than 27% of African Americans.

Characterisation of gastric cancer and its relation to environmental factors: a case study in Shenqiu County, China

This article presents the results of spatial analysis of gastric cancer and its relation to environmental conditions in Shenqiu County, China. Retrospective data on gastric cancer mortality (GCM) were analysed at various spatial scales, with its relation to environmental factors explored at an appropriate scale. The results considered 2 × 2 km(2) grid as the optimal level for characterising GCM due to the highest Moran's I (I = 0.68, p < 0.01). Then, three clustering regions were clearly identified. Meanwhile, GCM was obviously associated with topography (r = -0.11, p < 0.10), farmland (r = 0.11, p < 0.10), population density (r = 0.10, p < 0.10) and river density (r = 0.11, p < 0.10) in the buffered zones. It indicates that spatial grid technique is suitable for characterising GCM in Shenqiu County, and that GCM was geographically associated with environmental conditions. We suggest that preventive measures for controlling the environment-related malignant neoplasm should not be limited in the regions suffering from this disease but be reasonably extended to surrounding areas.

Cancer cluster investigations: review of the past and proposals for the future

Residential clusters of non-communicable diseases are a source of enduring public concern, and at times, controversy. Many clusters reported to public health agencies by concerned citizens are accompanied by expectations that investigations will uncover a cause of disease. While goals, methods and conclusions of cluster studies are debated in the scientific literature and popular press, investigations of reported residential clusters rarely provide definitive answers about disease etiology. Further, it is inherently difficult to study a cluster for diseases with complex etiology and long latency (e.g., most cancers). Regardless, cluster investigations remain an important function of local, state and federal public health agencies. Challenges limiting the ability of cluster investigations to uncover causes for disease include the need to consider long latency, low statistical power of most analyses, uncertain definitions of cluster boundaries and population of interest, and in- and out-migration. A multi-disciplinary Workshop was held to discuss innovative and/or under-explored approaches to investigate cancer clusters. Several potentially fruitful paths forward are described, including modern methods of reconstructing residential history, improved approaches to analyzing spatial data, improved utilization of electronic data sources, advances using biomarkers of carcinogenesis, novel concepts for grouping cases, investigations of infectious etiology of cancer, and "omics" approaches.