Temporal association of prostate cancer incidence with World Trade Center rescue/recovery work

DNA Methylation as a Molecular Mechanism of Carcinogenesis in World Trade Center Dust Exposure: Insights from a Structured Literature Review

The collapse of the World Trade Center (WTC) buildings in New York City generated a large plume of dust and smoke. WTC dust contained human carcinogens including metals, asbestos, polycyclic aromatic hydrocarbons (PAHs), persistent organic pollutants (POPs, including polychlorinated biphenyls (PCBs) and dioxins), and benzene. Excess levels of many of these carcinogens have been detected in biological samples of WTC-exposed persons, for whom cancer risk is elevated. As confirmed in this structured literature review (n studies = 80), all carcinogens present in the settled WTC dust (metals, asbestos, benzene, PAHs, POPs) have previously been shown to be associated with DNA methylation dysregulation of key cancer-related genes and pathways. DNA methylation is, therefore, a likely molecular mechanism through which WTC exposures may influence the process of carcinogenesis.

Cancer incidence in World Trade Center rescue and recovery workers by race and ethnicity

INTRODUCTION

It is unclear whether differences in health outcomes by racial and ethnic groups among World Trade Center (WTC) rescue and recovery workers reflect those of the population of New York State (NYS) or show distinct patterns. We assessed cancer incidence in WTC workers by self-reported race and ethnicity, and compared it to population figures for NYS.

METHODS

A total of 61,031 WTC workers enrolled between September 11, 2001 and January 10, 2012 were followed to December 31, 2015. To evaluate the association between race/ethnicity and cancer risk, Poisson regression analysis was used to estimate hazard ratios (HR) adjusted for WTC exposure, age, calendar year, sex and, for lung cancer, cigarette smoking.

RESULTS

In comparison to Whites, Black workers had a higher incidence of prostate cancer (HR = 1.99, 95% CI = 1.69-2.34) and multiple myeloma (HR = 3.57, 95% CI = 1.97-6.45), and a lower incidence of thyroid (HR = 0.41, 95% CI = 0.22-0.78) and colorectal cancer (HR = 0.57; 95% CI = 0.33-0.98). Hispanic workers had a higher incidence of liver cancer (HR = 4.03, 95% CI = 2.23-7.28). Compared with NYS population, White workers had significantly higher incidence of prostate cancer (HR = 1.26, 95% CI = 1.18-1.35) and thyroid cancer (HR = 1.80, 95% CI = 1.55-2.08), while Black workers had significantly higher incidence of prostate cancer (HR = 1.22, 95% CI = 1.05-1.40).

CONCLUSION

Cancer incidence in WTC workers generally reflects data from the NYS population, but some differences were identified that merit further investigation.

All-cause and cause-specific mortality in a cohort of WTC-exposed and non-WTC-exposed firefighters

OBJECTIVE

To compare mortality rates in World Trade Center (WTC)-exposed Fire Department of the City of New York (FDNY) firefighters with rates in similarly healthy, non-WTC-exposed/non-FDNY firefighters, and compare mortality in each firefighter cohort with the general population.

METHODS

10 786 male WTC-exposed FDNY firefighters and 8813 male non-WTC-exposed firefighters from other urban fire departments who were employed on 11 September 2001 were included in the analyses. Only WTC-exposed firefighters received health monitoring via the WTC Health Programme (WTCHP). Follow-up began 11 September 2001 and ended at the earlier of death date or 31 December 2016. Death data were obtained from the National Death Index and demographics from the fire departments. We estimated standardised mortality ratios (SMRs) in each firefighter cohort versus US males using demographic-specific US mortality rates. Poisson regression models estimated relative rates (RRs) of all-cause and cause-specific mortality in WTC-exposed versus non-WTC-exposed firefighters, controlling for age and race.

RESULTS

Between 11 September 2001 and 31 December 2016, there were 261 deaths among WTC-exposed firefighters and 605 among non-WTC-exposed. Both cohorts had reduced all-cause mortality compared with US males (SMR (95% CI)=0.30 (0.26 to 0.34) and 0.60 (0.55 to 0.65) in WTC-exposed and non-WTC-exposed, respectively). WTC-exposed firefighters also had lower rates of all-cause mortality (RR=0.54, 95% CI=0.49 to 0.59) and cancer-specific, cardiovascular-specific and respiratory disease-specific mortality compared with non-WTC-exposed firefighters.

CONCLUSION

Both firefighter cohorts had lower than expected all-cause mortality. Fifteen years post 11 September 2001, mortality was lower in WTC-exposed versus non-WTC-exposed firefighters. Lower mortality in the WTC-exposed suggests not just a healthy worker effect, but additional factors such as greater access to free health monitoring and treatment that they receive via the WTCHP.

A 15-year follow-up study of mortality in a pooled cohort of World Trade Center rescue and recovery workers

INTRODUCTION

Hazardous exposures from the World Trade Center (WTC) terrorist attacks have been linked to increased incidence of adverse health conditions, often associated with increased mortality. We assessed mortality in a pooled cohort of WTC rescue/recovery workers over 15 years of follow-up.

MATERIALS AND METHODS

We analyzed mortality through 2016 in a pooled and deduplicated cohort of WTC rescue/recovery workers from three WTC-exposed cohorts (N = 60,631): the Fire Department of the City of New York (FDNY); the WTC Health Registry (WTCHR); and the General Responder Cohort (GRC). Standardized mortality ratios (SMRs) were estimated to assess mortality vs. the US and NY state populations. Multivariable Cox proportional hazards models were used to examine associations of WTC exposures (date of first arrival, working on the WTC debris pile) with mortality risk.

RESULTS

There were 1912 deaths over 697,943.33 person-years of follow-up. The SMR for all-cause mortality was significantly lower-than-expected, both when using US (SMR 0.43, 95% confidence interval [CI] 0.42-0.45) and NYS (SMR 0.51, 95% CI 0.49-0.53) as reference populations. SMRs were not elevated for any of the 28 major causes of death. Arriving at the WTC site on 9/11-9/17/2001 vs. 9/18/2001-6/30/2002 was associated with 30-50% higher risk of all-cause, heart disease and smoking-related mortality in non-FDNY/non-GRC members. Conversely, arriving on 9/11/2001 vs. 9/18/2001-6/30/2002 was associated with 40% lower all-cause and smoking-related mortality risk in FDNY members. Working on vs. off the WTC pile was associated with an increased risk of all-cause mortality in non-FDNY/non-GRC members (adjusted hazard ratio [aHR] 1.25, 95% CI 1.04-1.50), and cancer-specific mortality in GRC members (aHR 1.39, 95% CI 1.05-1.84), but lower mortality risks were found in FDNY members.

CONCLUSIONS

We did not observe excess mortality among WTC rescue/recovery workers compared with general populations. However, significantly increased mortality risks among some sub-groups with high WTC exposure warrant further investigation.

Characteristics of Cancers in Community Members Exposed to the World Trade Center Disaster at a Young Age

The destruction of the World Trade Center (WTC) towers on 11 September 2001 (9/11) released tons of dust and smoke into the atmosphere, exposing hundreds of thousands of community members (survivors) and responders to carcinogens. The WTC Environmental Health Center (WTC EHC) is a federally designated surveillance and treatment program for community members who were present in the New York City disaster area on 9/11 or during the months that followed. WTC EHC enrollment requires exposure to the WTC dust and fumes and a federally certifiable medical condition, which includes most solid and blood cancers. Several studies have described the prevalence and characteristics of cancers in responders and survivors exposed to the WTC dust and fumes as adults. Cancers in those exposed at a young age warrant specific investigation since environmental toxin exposure at a younger age may change cancer risk. We describe the characteristics of 269 cancer patients with 278 cancer diagnoses among WTC EHC enrollees who were young in age (aged 0 to 30) on 9/11. These include 215 patients with a solid tumor (79.9%) and 54 with a lymphoid and/or hematopoietic cancer (20.1%). Among them, 9 patients had a known second primary cancer. A total of 23 different types of cancer were identified, including cancer types rare for this age group. Many were diagnosed in individuals lacking traditional cancer-specific risk factors such as tobacco use. The current study is the first to report specifically on cancer characteristics of younger enrollees in the WTC EHC program.

Progress towards the 2030 sustainable development goals: direct and indirect impacts on neurological disorders

The United Nations' Sustainable Development Goals (SDGs) were set forth in 2015 as a blueprint for all nations to create a more sustainable future together. These 17 social, environmental, and economic goals have established targets to meet globally by the year 2030, with a focus on pro-poor initiatives, gender equality, and ending hunger. The relationship of the SDGs with neurological disorders and how the achievement of the SDGs intersects with the future of neurological practice have not been comprehensively examined. However, the incidence of neurological disorders, the outcomes of people living with neurological disorders, and the training of future neurologists can be interlinked, directly or indirectly, with programming for the SDGs and their eventual achievement. Each SDG is reviewed in the context of neurology. This lens can inform programming and policy, enhance research and training, and improve inter-sectoral action for neurological disorders worldwide.

Cancer risk among World Trade Center rescue and recovery workers: A review

Twenty years after the September 11th, 2001 terrorist attacks, the association between exposures present at the World Trade Center (WTC) site and the risk of several specific types of cancer has been reported among rescue and recovery workers. The authors' objective was to conduct an updated review of these data. Most studies have found elevated rates of both prostate and thyroid cancers compared with rates in the general population, and some have reported statistically significant differences for the rates of all cancers as well. Studies including a larger combined cohort of WTC-exposed rescue and recovery workers from 3 main cohorts have since replicated findings for these cancers, with additional years of follow-up. Among this combined cohort, although a lower-than-expected standardized incidence ratio for all cancers was observed, WTC exposure was also related to an increased risk of cutaneous melanoma and tonsil cancer. Importantly, another study found that WTC-exposed rescue and recovery workers who are enrolled in the federally funded medical monitoring and treatment program experienced improved survival post-cancer diagnosis compared with New York state patients with cancer. On the basis of these combined cohort studies, the full effect of WTC exposure on cancer risk is becoming clearer. Consequently, the authors believe that surveillance of those with WTC exposure should be continued, and in-depth analysis of epidemiologic, molecular, and clinical aspects of specific cancers in these workers should be pursued.

World Trade Center dust exposure promotes cancer in PTEN-deficient mouse prostates

During the 9/11 attacks individuals were exposed to World Trade Center (WTC) dust which contained a complex mixture of carcinogens. Epidemiological studies have revealed the increased incidence of prostate and thyroid cancer in WTC survivors and responders. While reports have shown that WTC-dust associates with the increased prevalence of inflammatory related disorders, studies to date have not determined whether this exposure impacts cancer progression. In this study, we have used genetically engineered mouse (GEM) models with prostate specific deletion of the PTEN tumor suppressor to study the impact of WTC-dust exposure on deposition of dust particles, inflammation, and cancer progression. In normal C57/BL6 mice, dust exposure increased cellular expression of inflammatory genes with highest levels in the lung and peripheral blood. In normal and tumor bearing GEM mice, increased immune cell infiltration to the lungs was observed. Pathological evaluation of mice at different time points showed that WTC-dust exposure promoted PI3K-AKT activation, increased epithelial proliferation and acinar invasion in prostates with heterozygous and homozygous Pten loss. Using autochthonous and transplant GEM models of prostate cancer we demonstrated that dust exposure caused reduced survival as compared to control cohorts. Finally, we used imaging mass cytometry (IMC) to detect elevated immune cell infiltration and cellular expression of inflammatory markers in prostate tumors isolated from human WTC survivors. Collectively, our study shows that chronic inflammation, induced by WTC dust exposure, promotes more aggressive cancer in genetically predisposed prostates and potentially in patients.

Cancer incidence in World Trade Center-exposed and non-exposed male firefighters, as compared with the US adult male population: 2001-2016

OBJECTIVE

To compare cancer incidence in Fire Department of the City of New York (FDNY) firefighters who worked at the World Trade Center (WTC) site to incidence in a population of non-WTC-exposed firefighters, the Career Firefighter Health Study (CFHS) cohort, and to compare rates from each firefighter cohort to rates in demographically similar US males.

METHODS

FDNY (N=10 786) and CFHS (N=8813) cohorts included male firefighters who were active on 11 September 2001 (9/11) and were followed until death or 31 December 2016. Cases were identified from 15 state cancer registries. Poisson regression models assessed cancers in each group (FDNY and CFHS) versus US males, and associations between group and cancer rates; these models estimated standardised incidence ratios (SIRs) and adjusted relative rates (RRs), respectively. Secondary analyses assessed surveillance bias and smoking history.

RESULTS

We identified 915 cancer cases in 841 FDNY firefighters and 1002 cases in 909 CFHS firefighters. FDNY had: higher rates for all cancers (RR=1.13; 95% CI 1.02 to 1.25), prostate (RR=1.39; 95% CI 1.19 to 1.63) and thyroid cancer (RR=2.53; 95% CI 1.37 to 4.70); younger median ages at diagnosis (55.6 vs 59.4; p<0.001, all cancers); and more cases with localised disease when compared with CFHS. Compared with US males, both firefighter cohorts had elevated SIRs for prostate cancer and melanoma. Control for surveillance bias in FDNY reduced most differences.

CONCLUSIONS

Excess cancers occurred in WTC-exposed firefighters relative to each comparison group, which may partially be explained by heightened surveillance. Two decades post-9/11, clearer understanding of WTC-related risk requires extended follow-up and modelling studies (laboratory or animal based) to identify workplace exposures in all firefighters.