MedicalResearch.com Interview with:
Julie Sosa, MD MA FACS
Professor of Surgery and Medicine
Chief, Section of Endocrine Surgery
Director, Surgical Center for Outcomes Research
Leader, Endocrine Neoplasia Diseases Group
Duke Cancer Institute and Duke Clinical Research Institute
Durham, NC 2771
MedicalResearch.com: What is the background for this study?
Response: The incidence of thyroid cancer has dramatically increased world-wide over the last several decades. In the United States, thyroid cancer is the fastest increasing cancer among women and men. This observation has been almost exclusively the result of an epidemic of papillary thyroid cancer, or PTC, which now comprises approximately 90% of new cases.
The use of flame retardant chemicals, or Flame Retardant Chemicals, also increased over the last several decades due to the implementation of mandatory and voluntary flammability standards for furniture, electronics, and construction materials. Over time, FRs come out of these products and accumulate in indoor environments where humans are exposed. Animal studies suggest that FRs can disrupt thyroid function, and many contribute to cancer risk. But many human health endpoints have not been investigated.
Our work was aimed at investigating whether exposure to Flame Retardant Chemicals could be associated with PTC. To address our research question, we recruited 140 adults, 70 with PTC and 70 who were healthy volunteers without evidence for thyroid cancer or thyroid disease. Then we visited participants’ homes and collected dust samples, a metric that we have previously shown is an indicator of long-term exposure to Flame Retardant Chemicals in the home.
MedicalResearch.com: What are the main findings?
Response: We found that the levels of some Flame Retardant Chemicals were higher in the homes of PTC cases, suggesting that they may contribute to the occurrence of PTC. Different patterns of cancer aggressiveness were associated with various FRs. For example, levels of an organophosphate flame retardant (i.e. TCEP, tris (2-chloroethyl) phosphate) were most strongly associated with larger tumors that extended outside the thyroid. Compared to controls, those with higher TCEP levels were about 4 times as likely to have tumors that extended outside the thyroid.
MedicalResearch.com: What should readers take away from your report?
Response: The incidence of thyroid cancer is quickly increasing, and the factors leading to this drastic increase are still not well understood. Better diagnosis, increased radiation exposure and obesity have been proposed as possible explanatory factors, but other environmental exposures also are likely playing a role. Identifying those exposures is critically important in the possible prevention of thyroid cancer. Our results suggest that exposure to some Flame Retardant Chemicals in the home environment may be associated with PTC. This is a critical concern, because these FRs are commonly found in American homes, and the levels of exposure to some Flame Retardant Chemicals are thought to be increasing.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Response: Our work is among the first to look at relationships between Flame Retardant Chemicals and thyroid cancer and disease. Our results suggest potential associations, but more research is needed to investigate relationships and determine if these trends can be replicated in a larger cohort. Understanding how these chemicals contribute to papillary thyroid cancer is also critically important; knowing the mechanism of action provides a possible opportunity to mitigate risk and could help to predict other health outcomes that could be related to exposure.
MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.
Citation: Abstract presented at ENDO 2017: The Endocrine Society’s 99th Annual Meeting & Expo
Exposure to Flame Retardant Chemicals and the Occurrence and Severity of Papillary Thyroid:Cancer: A Case-Control Study
Julie Ann Sosa, MD, MA, Duke University
Kate Hoffman, PhD, MSES, MPA
Amelia Lorenzo, BS2, Craig M. Butt, PhD
and Heather Stapleton, PhD
Surgery, Duke University, Durham, NC,
Nicholas School of the Environment, Duke University, Durham, NC.
Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.
More Medical Research Interviews on MedicalResearch.com