We have repeatedly discussed the problem of over-diagnosis and the consequences: treatment of cancers that would not harm the person in which they are found some breast and prostate cancers definitely fall into this category. A new study just published in JAMA Otolaryngology now extends this finding to thyroid cancer.
The thyroid is an endocrine gland situated in front of the trachea in the neck. It produces thyroid hormone which regulates many body processes, and is essential for life. If a cancerous thyroid is removed, then the patient must take synthetic thyroid hormone for the rest of his or her life. Thus a diagnosis of thyroid cancer is worrisome, to say the least.
Drs. Louise Davies and Gilbert Welch from the Dartmouth Institute for Health Policy and Clinical Practice examined data from the Surveillance, Epidemiology, and End Results (SEER) program and thyroid cancer mortality from the National Vital Statistics System. In particular, they investigated deaths from thyroid cancer occurring between 1975 and 2009 in men and women over 18 years of age.
They examined the data on thyroid cancer incidence, type, tumor size and mortality, and found that the incidence (new cases) of thyroid cancer nearly tripled (from 4.9 to 14.3 cases per 100,000 persons) between those dates. While that certainly sounds like a frightening statistic, the authors also found that most of this increase was due to an increase in papillary thyroid cancer a type that is not deadly. Further, many of the tumors were too small to ever become life-threatening. In addition, they found that the mortality rate from thyroid cancer had not increased between 1975 and 2009, which also suggests that the increased incidence was not due to deadly forms of the disease.
In their discussion, the authors note that the apparent epidemic of thyroid cancer in the United States does not seem to be an epidemic of disease. Instead, their data indicate that the problem is over-diagnosis. They suggest dealing with it by giving patients the option of active surveillance, and/or relabeling incidentally identified small thyroid lesions as something other than cancer.
ACSH s Dr. Gilbert Ross concurs When a person is told they have any type of cancer, it is natural for them to want to eradicate it. But, as with some types of breast or prostate cancer, this is not necessarily the best option. Watchful waiting may be a better choice than treatments that can have detrimental effects on quality of life but which are not necessary to control a disease.