By Lauryn Fairley
Lauryn Fairley is a junior biology and anthropology double major at UNC-Chapel Hill. She is working as an environmental policy intern with the NC Policy Collaboratory during the 2020 Fall semester.
The Complex Nature of Cancer
In the Fall semester of 2019, I had the opportunity to work as an undergraduate research assistant in the Jill Dowen Lab at UNC. Dr. Dowen’s lab studies cancer genetics, particularly the relationship between genome organization and gene expression in development and disease. Throughout my time working in the lab I came to realize the true complexity of cancer.
Cancer has touched the lives of most the people we know in some shape or form. In 2016, cancer was the leading cause of death in North Carolina. While we often think of cancer as singular disease, the reality is that cancer is a multitude of different diseases with a wide range of causes. Because of this, cancer research is also incredibly complex, as there are many contributing factors to the development of cancer.
Environmental Exposures and Cancer Clusters
When a community experiences an unusually high number of cancer cases, it may be referred to as a cancer cluster. The US Centers for Disease Control and Prevention defines a cancer cluster as a “greater than expected number of cancer cases that occurs within a group of people in a geographic area over a defined period of time.” When communities experience cancer clusters or multiple cancer diagnoses, concerns often arise about the role of environmental exposures.
Environmental exposures can cause cancer by damaging the DNA of our cells and changing the way they function. Well known environmental exposures are tobacco, radiation, and UV rays from the sun. While some environmental exposures can be avoided, others are much harder to avoid. Whether they are in the water we drink or the food we eat, identifying carcinogens, cancer causing agents, allows scientists to better understand environmental exposures and the causes of cancer clusters.
However, cancer clusters can be challenging to investigate as genetics, lifestyle, and environmental factors are all involved. Because of these multiple factors, cancer cluster investigations face difficulties – determining the cause of clusters. Difficulty establishing causality is displayed in the figure below; although there were over 500 cancer cluster investigations over a 20-year-period, only one cluster was able to establish causality.
Cancer Cluster Investigations in the United States 1990-2011. Source: Critical Reviews in Toxicology, 2012; 42(6): 474-490
Formation of the Cancer Research Advisory Panel
In response to concerns regarding possible cancer clusters in Iredell County, North Carolina, the North Carolina General Assembly approved legislation (Senate Bill 297, Session Law 2019-145) to convene an advisory panel on cancer research, with the purpose of developing strategies for the implementation of a research program to assess cancer incidence and mortality rates within the state.
This legislation directed the North Carolina Policy Collaboratory to assembly a panel of experts, including higher education faculty members, health care providers, and health insurance providers. The Collaboratory was required to submit final recommendations of the panel to the General Assembly by April 30, 2020.
The 22-member panel included epidemiologists, clinicians, and environmental scientists from five universities, and multiple local, state, and federal governmental agencies. The panel was chaired by Dr. Andy Olshan of UNC Lineberger Comprehensive Cancer Center.
Cancer Research Advisory Panel Recommendations
The Cancer Research Advisory Panel proposed five recommendations that encompass specific research, methodology and funding recommendations. The full details of the Advisory Panel’s recommendations are beyond the scope of this blog post, but a brief overview of each of the recommendations follows.
Improve Communication Process by Identifying One Single-Point-of-Contact Person for Health Departments, Community Members and Other Stakeholders
This recommendation would designate a contact person in the NC Department of Health and Humans Services for cancer cluster investigations. This would allow for early and consistent communication with residents and is critical to effective cancer cluster investigations.
Invest in More Robust Infrastructure to Strengthen Coordination and Implementation of Cancer Cluster Investigations Across North Carolina
The Advisory Panel recommended strengthening the NC Department of Health and Human Services team that coordinates cancer cluster investigations, through the creation of a cancer epidemiologist position dedicated to cancer cluster investigations.
Enhance Cancer Data Resources and Analytical Capabilities for Cancer Cluster Surveillance
The Advisory Panel recommended the improvement of thoroughness of cancer case reporting across the state through:
- improved statistical methods and software tools,
- enhancing surveillance and analysis of cancer patterns in North Carolina,
- the incorporation of carefully examined new tools,
- solutions into the NC cancer cluster protocol, and
- the development of a statewide training program on cancer case reporting for physicians.
Develop a NC Environmental Public Health Tracking Web-Portal
The Advisory Panel recommended conveying environmental hazard information via an online web-portal, known as Environmental Public Health Tracking, allowing residents to view comprehensive environmental and health data by time, geography, cancer type, age group, year, and other factors.
Convene a Cancer Cluster Advisory Committee
The Advisory Panel recommended convening an advisory committee to provide prompt input on issues related to suspected cancer clusters and to ensure that the development of best practices for cancer cluster investigation and responses are addressed.
A list of all of the recommendations can be found in the full North Carolina Cancer Research Advisory Panel Recommendations found at: https://collaboratory.unc.edu/files/2020/04/cancer-research-advisory-panel-recommendations.pdf
Future Action
Based on the Advisory Panel recommendations Senate Bill 746 and House Bill 1138 were introduced during the 2020 legislative session. The two pieces of legislation would have implemented and funded a number of the recommendations. The bills were not acted upon before the session adjourned.
As noted above, the Advisory Panel was in part prompted by concerns about a cancer cluster in Iredell County. In the summer of 2020 university researchers from UNC and Duke conducted soil sampling at several schools in Iredell County. The researchers are working with local government officials to share results of that analysis with the public.
The work of the Advisory Panel has provided a timely and detailed discussion about potential ways the state can address communities’ concerns with cancer clusters. The panel’s recommendations have the potential to catalyze and support efforts by medical professionals and public health officials.