By Jennifer K. Loukissas, M.P.P.
DCEG researchers study a wide range of potential causes of cancer, from inherited susceptibility to radiation-induced carcinogenesis. Among the specialty approaches they use to uncover novel causes of cancer are descriptive epidemiological studies. Meredith Shiels, Ph.D., a newly appointed tenure-track investigator in the Infections and Immunoepidemiology Branch (IIB), is one of a handful of researchers tracking and interrogating the patterns that emerge from cancer registry and mortality data.
As a co-principal investigator of the HIV/AIDS Cancer Match Study, Dr. Shiels is continuing her descriptive work on HIV and cancer while expanding her research focus to collaborate widely across DCEG to investigate other exposures and cancer sites. For example, by utilizing data from SEER-Medicare, which links cancer incidence and medical claims information, she is working to quantify the effect of viral hepatitis on increasing hepatocellular carcinoma rates. Similarly, she is carrying out a quantitative assessment of the impact of obesity on increasing rates of late stage, large thyroid cancers.
Dr. Shiels is also taking advantage of advancements in technology, such as The Cancer Genome Atlas, which have highlighted the importance of tumor characteristics beyond primary site and histology. Emerging molecular, genetic, hormonal, and viral markers that influence cancer treatment and prognosis are mostly missing from standard reports to registries.
“As descriptive studies provide clues into etiology, it is critical that we understand the demographics, geography, and trends of cancer based on refined tumor characteristics,” said Dr. Shiels. In order to do so, she and other epidemiologists within DCEG and at cancer registries, are linking information from pathology reports with existing trends data.
While pursuing her descriptive work, Dr. Shiels maintains her interest in tobacco research; she led several studies of cigarette smoking, lung cancer and immune dysfunction during her fellowship in IIB. The rapid emergence of new tobacco products paired with the recent expansion of regulatory authority for the U.S. Food and Drug Administration (FDA) has resulted in increased demand for evidence on health effects. With Neal D. Freedman, Ph.D., M.P.H., senior investigator, MEB, and others in the Division, Dr. Shiels is collaborating with the FDA and the Centers for Disease Control and Prevention to pilot a study of urinary levels of tobacco-specific metabolites in participants in the Golestan Cohort, whose members use more than one type of product, as well as those who use no tobacco. This effort will inform a future, large case-cohort study that is being designed to examine prospectively the association between these metabolites and smoking-related cancers.