Cancer death rates in US congressional districts.

Knowledge of the cancer burden is important for informing and advocating cancer prevention and control. Mortality data are readily available for states and counties, but not for congressional districts, from which representatives are elected and which may be more influential in compelling legislation and policy. The authors calculated average annual cancer death rates during 2002 to 2011 for each of the 435 congressional districts using mortality data from the National Center for Health Statistics and population estimates from the US Census Bureau. Age-standardized death rates were mapped for all sites combined and separately for cancers of the lung and bronchus, colorectum, breast, and prostate by race/ethnicity and sex. Overall cancer death rates vary by almost 2-fold and are generally lowest in Mountain states and highest in Appalachia and areas of the South. The distribution is similar for lung and colorectal cancers, with the lowest rates consistently noted in districts in Utah. However, for breast and prostate cancers, while the highest rates are again scattered throughout the South, the geographic pattern is less clear and the lowest rates are in Hawaii and southern Texas and Florida. Within-state heterogeneity is limited, particularly for men, with the exceptions of Texas, Georgia, and Florida. Patterns also vary by race/ethnicity. For example, the highest prostate cancer death rates are in the West and north central United States among non-Hispanic whites, but in the deep South among African Americans. Hispanics have the lowest rates except for colorectal cancer in Wyoming, eastern Colorado, and northern New Mexico. These data can facilitate cancer control and stimulate conversation about the relationship between cancer and policies that influence access to health care and the prevalence of behavioral and environmental risk factors.

Effect of soil particle size and extraction method on the oral bioaccessibility of arsenic.

Recent findings indicate that incidental ingestion of soil by humans primarily involves soil particles <150 µm, rather than <250 µm-sized fraction previously used for most oral bioaccessibility and bioavailability studies. It was postulated that a greater soil surface area in the finer fraction (<150 versus <250 µm) might increase oral bioaccessibility of arsenic (As) in soil. Bioaccessibility and concentrations of As were compared in <150 and <250 µm fractions of 18 soil samples from a variety of arsenic-contaminated sites. The two methods used to measure bioaccessibility were compared - EPA Method 1340 and the California Arsenic Bioaccessibility (CAB) method. Arsenic concentrations were nearly the same or higher in the <150 fraction compared with <250 µm. EPA Method 1340 and the CAB method presented significantly different bioaccessibility results, as well as estimated relative oral bioavailability (RBA) based upon algorithms specific to the methods, but there was no marked difference for <150 and <250 µm soil fractions within either method. When compared with RBA determined previously for these soil samples in vivo in non-human primates, EPA Method 1340 was generally more predictive than the CAB method. Data suggest that soil- or site-specific factors control bioaccessibility under either method and that the test method selected is more important than the particle size fraction (<150 or <250) in using these in vitro methods to predict As RBA for use in risk assessment.

Dose-response assessment for impaired memory from chronic exposure to domoic acid among native American consumers of razor clams.

Domoic acid (DA) is a marine neurotoxin that accumulates in filtering shellfish during harmful algal blooms. A health protection limit of 20 ppm DA in razor clams (RC) has been set based principally upon an episode of acute DA toxicity in humans that included Amnesic Shellfish Poisoning among survivors. The objective of this study was to determine the dose-response relationship between estimated DA exposure through RC consumption and memory loss in Washington state Native Americans from 2005 to 2015. Results from total learning recall (TLR) memory scores were compared before and after the highest DA exposures. A decrease in TLR was related to DA dose (p < 0.01) regardless whether the effect was assumed to be transient or lasting, and whether the dose was expressed as an average daily dose or an average dose per meal. Benchmark dose modeling identified BMDL10 values of 167 ng/kg-day and 2740 ng/kg-meal assuming a transient effect, and 196 ng/kg-day and 2980 ng/kg-meal assuming no recovery of function occurs. These DA dose thresholds for a measurable memory function reduction observed in this study of clam consumers are well below the safe acute dose underpinning the current regulatory DA limit of 20 ppm (ca. 60 µg/kg).

Topic Modeling of Smoking- and Cessation-Related Posts to the American Cancer Society's Cancer Survivor Network (CSN): Implications for Cessation Treatment for Cancer Survivors Who Smoke.

INTRODUCTION: Smoking is a risk factor in at least 18 cancers, and approximately two-thirds of cancer survivors continue smoking following diagnosis. Text mining of survivors' online posts related to smoking and quitting could inform strategies to reduce smoking in this vulnerable population. METHODS: We identified posts containing smoking/cessation-related keywords from the Cancer Survivors Network (CSN), an online cancer survivor community of 166 000 members and over 468 000 posts since inception. Unsupervised topic model analysis of posts since 2000 using Latent Dirichlet Allocation extracted 70 latent topics which two subject experts inspected for themes based on representative terms. Posterior analysis assessed the distribution of topics within posts, and the range of themes discussed across posts. RESULTS: Less than 1% of posts (n = 3998) contained smoking/cessation-related terms, and covered topics related to cancer diagnoses, treatments, and coping. The most frequent smoking-related topics were quit smoking methods (5.4% of posts), and the environment for quitters (2.9% of posts), such as the stigma associated with being a smoker diagnosed with cancer and lack of empathy experienced compared to nonsmokers. Smoking as a risk factor for one's diagnosis was a primary topic in only 1.7% of smoking/cessation-related posts. CONCLUSIONS: The low frequency of smoking/cessation-related posts may be due to expected criticism/stigma for smoking but may also suggests a need for health care providers to address smoking and assist with quitting in the diagnostic and treatment process. Topic model analysis revealed potential barriers that should be addressed in devising clinical or population-level interventions for cancer survivors who smoke. IMPLICATIONS: Although smoking is a major risk factor for cancer, little is known about cancer patients' or survivors' views or concerns about smoking and quitting. This study used text mining of posts to an online community of cancer patients and survivors to investigate contexts in which smoking or quitting is discussed. Results indicated that smoking and quitting discussions were relatively rare, but nevertheless provide insight into barriers that may need to be addressed in cessation interventions for survivors.

American Cancer Society perspectives on environmental factors and cancer.

Cancer prevention is central to the mission of the American Cancer Society (ACS). The ACS's prevention activities take many forms, but are primarily focused on modifiable risk factors that have been demonstrated to have the largest impact on cancer risk in the general population (with particular emphasis on tobacco use because of its large impact on cancer), and well-proven policy and program interventions. The ACS addresses nutrition, physical inactivity and obesity, alcohol consumption, excessive sun exposure, prevention of certain chronic infections, and selected other environmental factors through a variety of venues, including consensus guidelines (eg, nutrition and physical activity, human papillomavirus vaccination) and developing educational materials for health care providers and the general public. In contrast to the broad definition of environmental factors used by the ACS and most other public health agencies, some members of the general public associate the term "environmental" only with toxic air and water pollutants and other, predominantly manmade, hazards that people encounter, often involuntarily, in their daily life. This article will provide an overview of the ACS's approach to the prevention of cancer associated with such toxic pollutants in the context of its mission and priorities with respect to cancer prevention.

Association between urologist characteristics and radiation oncologist consultation for patients with locoregional prostate cancer.

BACKGROUND: Physicians managing patients with prostate cancer play a critical role in subsequent specialist consultations and initial treatment choice, especially in cases for which no consensus exists regarding optimal treatment strategy. The NCCN Guidelines for Prostate Cancer recommend radiation as a therapy option for patients with locoregional prostate cancer. PURPOSE: The authors examined the association of urologist characteristics with the likelihood that patients would consult radiation oncologists. METHODS: A retrospective cohort of 39,934 patients aged 66 years or older who were diagnosed with locoregional prostate cancer between 2004 and 2007, and the 2405 urologists who performed the patient diagnostic biopsies were constructed using the SEER-Medicare linked database and the American Medical Association Physician Masterfile. Logistic multilevel regression analysis was used to evaluate the influence of urologists' characteristics on radiation oncologist consultation within 9 months of locoregional prostate cancer diagnosis. RESULTS: Overall, 24,549 (61.5%) patients consulted a radiation oncologist. After adjusting for patient and urologist characteristics, patients diagnosed by urologists in noninstitutional settings (eg, physician office) were significantly more likely to consult a radiation oncologist (odds ratio [OR], 1.40; 95% CI, 1.17-1.67; P=.0002) compared with those diagnosed by urologists in institutional settings with a major medical school affiliation. In addition, patients diagnosed by urologists older than 57 years were significantly more likely to consult a radiation oncologist (OR, 1.21; 95% CI, 1.07-1.38, P=.003).

Determinants of the combined use of external beam radiotherapy and brachytherapy for low-risk, clinically localized prostate cancer.

BACKGROUND: Prostate cancer treatment choices have been shown to vary by physician and patient characteristics. For patients with low-risk, clinically localized prostate cancer, the authors examined the impact of their clinical, sociodemographic, and radiation oncologists' (RO) characteristics on the likelihood that the patients would receive combined external beam radiotherapy and brachytherapy, a treatment regimen that is at variance with clinical guidelines. METHODS: The Surveillance, Epidemiology and End Results (SEER)-Medicare linked database and the American Medical Association Physician Masterfile were used in a retrospective analysis of 5531 patients with low-risk, clinically localized prostate cancer who were diagnosed between 2004 and 2007, and the 708 ROs who treated them. Hierarchical logistic regression analyses were used to evaluate the relationship between patient and RO characteristics and the use of combined therapy within 6 months of diagnosis. RESULTS: Overall, 356 patients (6.4%) received combined therapy. Nonclinical factors were found to be associated with combined therapy. After adjusting for patient and RO characteristics, the odds of receiving combined therapy for patients residing in Georgia were found to be significantly greater than for all other SEER regions. Black patients were significantly less likely to receive combined therapy (odds ratio, 0.62; 95% confidence interval, 0.40-0.96 [P= .03]) compared with white patients. In addition, ROs accounted for 36.6% of the variation in patients receiving combined therapy. CONCLUSIONS: Geographic and sociodemographic factors were found to be significantly associated with guideline-discordant combined therapy for patients diagnosed with low-risk, clinically localized prostate cancer. Which RO a patient consults is important in determining whether they receive combined therapy.

Density-dependent habitat selection and performance by a large mobile reef fish.

Many exploited reef fish are vulnerable to overfishing because they concentrate over hard-bottom patchy habitats. How mobile reef fish use patchy habitat, and the potential consequences on demographic parameters, must be known for spatially explicit population dynamics modeling, for discriminating essential fish habitat (EFH), and for effectively planning conservation measures (e.g., marine protected areas, stock enhancement, and artificial reefs). Gag, Mycteroperca microlepis, is an ecologically and economically important warm-temperate grouper in the southeastern United States, with behavioral and life history traits conducive to large-scale field experiments. The Suwannee Regional Reef System (SRRS) was built of standard habitat units (SHUs) in 1991-1993 to manipulate and control habitat patchiness and intrinsic habitat quality, and thereby test predictions from habitat selection theory. Colonization of the SRRS by gag over the first six years showed significant interactions of SHU size, spacing, and reef age; with trajectories modeled using a quadratic function for closely spaced SHUs (25 m) and a linear model for widely spaced SHUs (225 m), with larger SHUs (16 standardized cubes) accumulating significantly more gag faster than smaller 4-cube SHUs (mean = 72.5 gag/16-cube SHU at 225-m spacing by year 6, compared to 24.2 gag/4-cube SHU for same spacing and reef age). Residency times (mean = 9.8 mo), indicative of choice and measured by ultrasonic telemetry (1995-1998), showed significant interaction of SHU size and spacing consistent with colonization trajectories. Average relative weight (W(r)) and incremental growth were greater on smaller than larger SHUs (mean W(r) = 104.2 vs. 97.7; incremental growth differed by 15%), contrary to patterns of abundance and residency. Experimental manipulation of shelter on a subset of SRRS sites (2000-2001) confirmed our hypothesis that shelter limits local densities of gag, which, in turn, regulates their growth and condition. Density-dependent habitat selection for shelter and individual growth dynamics were therefore interdependent ecological processes that help to explain how patchy reef habitat sustains gag production. Moreover, gag selected shelter at the expense of maximizing their growth. Thus, mobile reef fishes could experience density-dependent effects on growth, survival, and/or reproduction (i.e., demographic parameters) despite reduced stock sizes as a consequence of fishing.

Effects of local extinction of the plains vizcacha (Lagostomus maximus) on vegetation patterns in semi-arid scrub.

We studied spatial and temporal effects of local extinction of the plains vizcacha (Lagostomus maximus) on plant communities following widespread, natural extinctions of vizcachas in semi-arid scrub of Argentina. Spatial patterns in vegetation were examined along transects extending outward from active and extinct vizcacha burrow systems. Responses of vegetation to removal of vizcachas were assessed experimentally with exclosures and by documenting vegetation dynamics for 6 years following extinctions. Transect data demonstrated clear spatial patterns in plant cover, particularly an increase in perennial grasses, outward from active vizcacha burrows. These patterns were consistent with predictions based on foraging theory and studies that document grasses as the preferred food of vizcachas. Removal of vizcachas, experimentally and with extinctions, resulted in an immediate increase in perennial and annual forbs indicating that intense herbivory can depress forb cover, as well as grasses. After a 1-year lag following cessation of herbivory, cover of grasses increased. Forbs declined as grasses increased. The long-term effect of extinction of vizcachas was a conversion of colony sites from open patches dominated by forbs to dense bunch grass characteristic of the matrix. Major changes in vegetation occurred within 2-3 years after extinction, resulting in a large pulse of landscape change. However, some species of grasses were uncommon until 5-6 years after the vizcacha extinction. With extinction and colonization, vizcachas generate a dynamic mosaic of patches on the landscape and create temporal, as well as spatial, heterogeneity in semi-arid scrub.

Nitrogen removal and nitrate leaching for forage systems receiving dairy effluent.

Florida dairies need year-round forage systems that prevent loss of N to ground water from waste effluent sprayfields. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentrations in soil water below the rooting zone for two forage systems during four 12-mo cycles (1996-2000). Soil in the sprayfield is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzipsamment). Over four cycles, average loading rates of effluent N were 500, 690, and 910 kg ha(-1) per cycle. Nitrogen removed by the bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (BR) during the first three cycles was 465 kg ha(-1) per cycle for the low loading rate, 528 kg ha(-1) for the medium rate, and 585 kg ha(-1) for the high. For the corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye system (CSR), N removals were 320 kg ha(-1) per cycle for the low rate, 327 kg ha(-1) for the medium, and 378 kg ha(-1) for the high. The higher N removals for BR were attributed to higher N concentration in bermudagrass (18.1-24.2 g kg(-1)) than in corn and forage sorghum (10.3-14.7 g kg(-1)). Dry matter yield declined in the fourth cycle for bermudagrass but N removal continued to be higher for BR than CSR. The BR system was much more effective at preventing NO3(-)-N leaching. For CSR, NO3(-)-N levels in soil water (1.5 m below surface) increased steeply during the period between the harvest of one forage and canopy dosure of the next. Overall, the BR system was better than CSR at removing N from the soil and maintaining low NO3(-)-N concentrations below the rooting zone.

Nitrogen removal and nitrate leaching for two perennial, sod-based forage systems receiving dairy effluent.

In northern Florida, year-round forage systems are used in dairy effluent sprayfields to reduce nitrate leaching. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentration below the rooting zone for two perennial, sod-based, triple-cropping systems over four 12-mo cycles (1996-2000). The soil is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzip-samment). Effluent N rates were 500, 690, and 910 kg ha(-1) per cycle. Differences in N removal between a corn (Zea mays L.)-bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (CBR) and corn-perennial peanut (Arachis glabrata Benth.)-rye system (CPR) were primarily related to the performance of the perennial forages. Nitrogen removal of corn (125-170 kg ha(-1)) and rye (62-90 kg ha(-1)) was relatively stable between systems and among cycles. The greatest N removal was measured for CBR in the first cycle (408 kg ha(-1)), with the bermudagrass removing an average of 191 kg N ha(-1). In later cycles, N removal for bermudagrass declined because dry matter (DM) yield declined. Yield and N removal of perennial peanut increased over the four cycles. Nitrate N concentrations below the rooting zone were lower for CBR than CPR in the first two cycles, but differences were inconsistent in the latter two. The CBR system maintained low NO3(-)-N leaching in the first cycle when the bermudagrass was the most productive; however, it was not a sustainable system for long-term prevention of NO3(-)-N leaching due to declining bermudagrass yield in subsequent cycles. For CPR, effluent N rates > or = 500 kg ha(-1) yr(-1) have the potential to negatively affect ground water quality.

Association of reimbursement policy and urologists' characteristics with the use of medical androgen deprivation therapy for clinically localized prostate cancer.

OBJECTIVES: Physician characteristics and changes in drug reimbursement rates have been shown to influence practice patterns regardless of clinical guidelines, patient, clinical, or sociodemographic factors. We concurrently examined the association between urologists׳ characteristics and non-evidence-based use of primary medical androgen deprivation therapy (ADT) for clinically localized patients with prostate cancer, before and after the 2003 Medicare Modernization Act׳s reductions in ADT reimbursement rates. METHODS AND MATERIALS: The Surveillance, Epidemiology, and End Results-Medicare-linked database and the American Medical Association Physician Masterfile are used in a retrospective analysis of 12,255 patients diagnosed between 2001 and 2007 with clinical stage T1-T2, low- to intermediate-grade prostate cancer, and the 1,863 urologists who treated them. Logistic multilevel regression analyses are used to evaluate the association of urologists׳ characteristics on ADT use among patients within 6 months of diagnosis. RESULTS: Overall, 3,866 (32%) patients received non-evidence-based ADT. After adjusting for patient and urologist characteristics, patients treated by urologists with no medical school affiliations, compared with those treated by urologists with major medical school affiliations, are significantly more likely to receive non-evidence-based medical ADT (odds ratio = 2.35; 95% CI: 1.71-3.23; P<0.0001). Non-US-trained urologists are also more likely to prescribe non-evidence-based medical ADT (odds ratio = 1.64; 95% CI: 1.33-2.04; P<0.0001). CONCLUSIONS: Patients treated by non-medical school-affiliated or non-US-trained urologists or both are significantly more likely to receive non-evidence-based ADT before and after the passage of the Medicare Modernization Act. Better strategies to encourage evidence-based ADT use on clinically localized patients with prostate cancer may be of benefit especially among non-medical school-affiliated or non-US-trained urologists or both.

Geographical variation in ribotype profiles of Escherichia coli isolates from humans, swine, poultry, beef, and dairy cattle in Florida.

Waters impacted by fecal pollution can exact high risks to human health and can result in financial losses due to closures of water systems used for recreation and for harvesting seafood. Identifying the sources of fecal pollution in water is paramount in assessing the potential human health risks involved as well as in assessing necessary remedial action. Recently, various researchers have used the ribotyping method to identify sources of bacterial indicators (Escherichia coli and enterococci) in environmental waters. While these studies have identified genotypic differences between human- and animal-derived indicators that are capable of differentiating organisms isolated from humans and various animal hosts, most have focused on organisms collected from a confined geographic area and have not addressed the question of whether these ribotype profiles are watershed specific or if they can be applied universally to organisms from other geographic locations. In this study, E. coli isolates were obtained from humans, beef cattle, dairy cattle, swine, and poultry from locations in northern, central, and southern Florida and were subjected to ribotyping analysis. The intent was to determine (i) if ribotype profiles are capable of discriminating the source of E. coli at the host species level and (ii) if the resulting fingerprints are uniform over an extended geographic area or if they can be applied only to a specific watershed. Our research indicated that, using a single restriction enzyme (HindIII), the ribotyping procedure is not capable of differentiating E. coli isolates from the different animal species sampled in this study. Results indicate, however, that this procedure can still be used effectively to differentiate E. coli as being either human or animal derived when applied to organisms isolated from a large geographic region.