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Thyroid Cancer Diagnosis Has Created an Artificial Epidemic

Doctors around the world are overdiagnosing the most common thyroid cancer, creating an artificial epidemic that costs billions of dollars each year in unnecessary medical costs. Global diagnoses of differentiated thyroid cancer have increased threefold during the past 25 years yet there has been no change to the disease’s low death rate.

A/Prof Suhail Doi of The Australian National University’s Research School of Population Health analysed international autopsy data from regions that had high and low instances of differentiated thyroid cancer over six decades from the 1960s. He found that incidental differentiated thyroid cancer has remained unchanged, confirming for the first time that the epidemic has been driven by increasing detections of cancer.

“Overly meticulous examinations are detecting the condition in the early stages and resulting in unnecessary surgeries,” Doi said. “Active monitoring rather than intervention is appropriate in many cases, similar to how doctors treat prostate cancer today.”

Differentiated thyroid cancer mainly involves papillary and follicular tumours that don’t usually progress to clinical forms of cancer. Around 2500 new cases of differentiated thyroid cancer are diagnosed in Australia each year.

Thyroid cancer surgery has substantial consequences for patients. Most patients must receive lifelong thyroid-replacement therapy, and some have complications from the procedure, including damage to nerves and surrounding glands.

Doi said his research, published in the Journal of Clinical Oncology, would inform clinical guidelines around the world on appropriate treatment for differentiated thyroid cancer, and also help to educate the public about the condition.

“People with this type of thyroid cancer can sometimes live until normal life expectancy and usually die from other causes, so there is no point intervening if the cancer is acting in a benign way and not causing any problems,” Doi said. “Only some of these cases require treatment if and when the condition progresses to clinical forms of cancer.”

In 2019 the projected medical care costs for differentiated thyroid cancer in the United States is estimated to be more than US$3 billion. “The medical costs for differentiated thyroid cancer in Australia could be about $US300 million in 2019 if we extrapolate from the US projection,” Doi said.