(RxWiki News) Thyroid cancer rates are increasing in the US. But one state may be contributing to the rising rate more than the others.
While thyroid cancer has increased steadily since the 1970s, the increase in thyroid cancer cases per year in Pennsylvania is nearly twice that of the US average.
The increase could be due to better detection technology or an actual increase in the occurrence of the disease, said the authors of a recent study.
"Have regular physical exams with your primary care doctor."
"Many tumors are being picked up appropriately by physicians and even dentists doing a comprehensive examination of the neck," said D. Gregory Farwell, MD, FACS, director of Head and Neck Oncology and Microvascular Surgery at the University of California, Davis.
"There is increased medical and public awareness of this tumor and health care professionals are looking for them. The biggest change, however, and the major advance in detection, has been the availability and utility of ultrasound screening," said Dr. Farwell, who was not involved in the recent study.
"Ultrasound can routinely detect and characterize many tumors that are too small to be felt. As such, we are finding many tumors that may have never been detected or become clinically important. This is creating some similar issues to what public health is dealing with when it comes to mammography screening and prostate screening where we may be detecting small tumors that may never be relevant to patient's survival. The potential harm in trying to diagnose and treat these small tumors may not be in the patient's best interest," he explained.
"Unfortunately, at this point, we do not have the ability to predict which tumors will be important to treat," Dr. Farwell said. "However, organizations such as the American Head and Neck Society and the American Thyroid Association are working to help physicians with guidelines that discourage inappropriate testing. This will hopefully allow us to get closer to the ideal of appropriately detecting tumors likely to cause problems without putting patients with tiny, insignificant tumors at undue risk."
To compare thyroid cancer rates, a research team reviewed data from 110,615 cases in the US and on 29,030 cases in the Pennsylvania Cancer Registry from 1985 to 2009.
The study was led by David Goldenberg, MD, from the Division of Otolaryngology in the Department of Surgery at the Milton S. Hershey Medical Center, and Darrin Bann, PhD — both from the Penn State College of Medicine in Hershey, PA.
The data showed that thyroid cancer cases in the US increased by 4.2 percent per year.
The increase in thyroid cancer cases in Pennsylvania was 7.1 percent per year.
Among thyroid cancer patients in Pennsylvania, women and whites had greater increases than men and blacks.
The authors noted that the increased use of imaging techniques may have led to the discovery of thyroid tumors that may not have been found in cases without symptoms.
However, the fact that the rate of large and advanced tumors was rising faster than the US average in Pennsylvania led the researchers to believe that the increase was due to more disease, not more diagnoses.
"Although the reasons underlying this increase in disease are not yet known, further research may help define potential environmental or genetic factors that can explain the rise of thyroid cancer," the authors wrote.
The research was published Aug. 28 in the online version of JAMA Otolaryngology.
A grant from the National Cancer Institute funded the research. The authors did not disclose any conflicts of interest.