Cancer Incidence, Latency, and Survival in World Trade Center Rescue/Recovery Workers

Tens of thousands of workers responded to the September 11, 2001, terrorist attacks on the World Trade Center (WTC) in New York City. The 9/11-exposed workforce includes police officers, firefighters, construction workers, communications workers, emergency medical services personnel, and a wide variety of other workers and community volunteers. These workers were exposed to a wide variety of known and potential cancer-causing agents and other hazards during response and recovery efforts, which lasted almost a year. There are two general occupational groups (general responders and responders affiliated with the Fire Department of the City of New York [FDNY]) being medically monitored and treated for health conditions related to 9/11 exposure, and which are organized around six WTC Clinical Centers of Excellence (CCE), with WTC Data Centers at Icahn School of Medicine at Mount Sinai and FDNY.  A third occupational group consists of workers enrolled in the WTC Health Registry, managed by the New York City Department of Health and Mental Hygiene, which periodically surveys its registrants but does not provide healthcare services (i.e., this is not a CCE).  All these entities are program components of the federal WTC Health Program that is administered by the National Institute for Occupational Safety and Health (NIOSH) at the Centers for Disease Control and Prevention (CDC).

In addition to the ethical imperative to support the 9/11-exposed workforce, there are potential benefits to science in studying cancer among workers responding to disasters. The relatively short-term exposure followed by long term follow-up allows for the study of changes in cancer risk over time for different cancers –an area for which there is limited data in human populations. The long-term follow-up also offers opportunities to evaluate effectiveness of screening, medical monitoring, and treatment. And there are also opportunities to learn more about cancer etiology in a high-risk population.

Previous cancer studies of the separate exposed groups were limited by small numbers and differences in methodologies used across studies. To address these limitations, researchers from the Albert Einstein College of Medicine and funded through the WTC Health Program combined these groups for joint examination. The study required information from 13 state cancer registries, the National Death Index, and New York City and State Vital Records. Results from this three-year effort are now available [1,2] and are briefly described below.

The study:

• Found previously unreported increased risk of tonsil cancer in 9/11 workers compared to the New York State general population. [2]
• Confirmed prior findings of elevated incidence of thyroid cancer, skin melanoma, and prostate cancer among 9/11 workers.
• Confirmed the findings showing reduced risk of lung cancer in this occupational group. This might be the result of low smoking rates in these workers compared to the general population.
• Did not confirm the prior findings of elevated risk for non-Hodgkin lymphoma or multiple myeloma.
• Found shorter latency periods for prostate cancer [2] and skin melanoma [3] than had been expected. These findings support further follow-up to continue to characterize cancer in the 9/11 workforce.
• Found that cancer patients have improved survival when participating in the medical monitoring and treatment program sponsored by the NIOSH WTC Health Program compared to the New York State general population. [4]
  • Specifically, workers with prostate, lung, kidney, and colorectal cancer had mortality rates that were 26% to 64% lower than that in the general population.
  • Similar benefits were observed for workers with skin melanoma, multiple myeloma, esophageal cancer, and liver cancer.

These findings support continued outreach to the 9/11-exposed population to encourage enrollment into one of the NIOSH-sponsored WTC MMTPs.

Charles B. Hall, PhD, is a Professor in the Department of Epidemiology and Population Health at the Albert Einstein College of Medicine.

The World Trade Center (WTC) Health Program is administered by the National Institute for Occupational Safety and Health (NIOSH). NIOSH has funded research projects designed to help answer critical questions about the physical and mental health conditions related to the 9/11 terrorist attacks. This research plays a vital role in the health conditions currently covered by the WTC Health Program (see WTC-Related List of Covered Health Conditions) and the Program’s ability to add health conditions to the list.  For more information see the WTC Health Program gateway.

References

[1] Brackbill RM, Kahn AR, Li J, Zeig-Owens R, Goldfarb DG, Skerker M, Farfel MR, Cone JE, Yung J, Walker DJ, Solomon A, Qiao B, Schymura MJ, Dasaro CR, Kristjansson D, Webber MP, Luccini RG, Todd AC, Prezant DJ, Boffetta P, Hall CB. Combining Three Cohorts of World Trade Center Rescue/Recovery Workers for Assessing Cancer Incidence and Mortality. Int J Environ Res Public Health. 2021 Feb 3;18(4):1386. doi: 10.3390/ijerph18041386. PMID: 33546187; PMCID: PMC7913216.

[2] Goldfarb DG, Zeig-Owens R, Kristjansson D, Li J, Brackbill RM, Farfel MR, Cone JE, Yung J, Kahn AR, Qiao B, Schymura MJ, Webber MP, Dasaro CR, Shapiro M, Todd AC, Prezant DJ, Boffetta P, Hall CB. Temporal association of prostate cancer incidence with World Trade Center rescue/recovery work. Occup Environ Med. 2021 Oct;78(10):699-706. doi: 10.1136/oemed-2021-107405. Epub 2021 Sep 10. PMID: 34507966; PMCID: PMC8458078.

[3] Boffetta P, Goldfarb DG, Zeig-Owens R, Kristjansson D, Li J, Brackbill RM, Farfel MR, Cone JE, Yung J, Kahn AR, Qiao B, Schymura MJ, Webber MP, Prezant DJ, Dasaro CR, Todd AC, Hall CB. Temporal Aspects of the Association between Exposure to the World Trade Center Disaster and Risk of Cutaneous Melanoma. JID Innovations (2022);2:100063. doi:10.1016/j.xjidi.2021.100063.

[4] Goldfarb DG, Zeig-Owens R, Kristjansson D, Li J, Brackbill RM, Farfel MR, Cone JE, Kahn AR, Qiao B, Schymura MJ, Webber MP, Dasaro CR, Lucchini RG, Todd AC, Prezant DJ, Hall CB, Boffetta P. Cancer survival among World Trade Center rescue and recovery workers: A collaborative cohort study. Am J Ind Med. 2021 Oct;64(10):815-826. doi: 10.1002/ajim.23278. Epub 2021 Jul 19. PMID: 34288025; PMCID: PMC8515734.