This site is intended for health professionals only

New imaging methods blamed for rise in thyroid cancer ‘overdiagnosis’

US experts have warned against the use of new imaging techniques and their association with overdiagnosis of thyroid cancers.

The experts warned in the BMJ today that thyroid cancers that are unlikely to advance to cause symptoms or death are being diagnosed and treated.

They claims that technologies such as CT, MRI and ultrasound scanning enable thyroid nodules in the region of 2mm, many of which are papillary thyroid cancers, to be picked up.

Despite cases in the US tripling over the past 10 years – from 3.6 per 100,000 in 1973 to 11.6 per 100,000 in 2009 – and it being one of the fastest growing diagnoses, its death rate has remained stable.

This warning is part of a BMJ series which assesses the risks and harms of overdiagnosis in an array of common conditions.

The authors argued that the increasing discrepancy between incidence of and death from thyroid cancers points to low risk cancers being overdiagnosed. They warned that the treatment that follows is unnecessary, harmful and at odds with the patient’s prognosis.

‘Both the overdiagnosis and overtreatment of this type of cancer need to be fully recognised,’ they added.

They also warned that with unnecessary thyroidectomy comes a risk of complications, for example low calcium levels and nerve injury, as well as expense; the US has experienced a rise of 60% in the past 10 years in thyroidectomies for thyroid cancer, costing in the region of £270million.