NIFTP Will Reduce the Overdiagnosis of Thyroid Cancer

An article about the impact of NIFTP (noninvasive follicular thyroid neoplasm with papillary-like nuclear features) appeared in the New York Times on April 14th.  Written by Gina Kolata, it informs readers of a change in nomenclature for a type of thyroid cancer known as noninvasive encapsulated follicular variant.  The change to NIFTP means that this type of thyroid cancer would no longer be considered malignant, hence the title of the Times article: “It’s not Cancer: Doctors Reclassify a Thyroid Tumor”.  The article estimates the change in classification will affect approximately 10,000 patients a year in the United States alone and quotes prominent members of the American Thyroid Association as being in support of the transition to NIFTP.

Thyroid Cancer is an increasingly diagnosed disease that affects approximately 64,000 people per year in the United States, and consists of several varieties.  About 70% are papillary thyroid cancers, which also have the best overall survival rates of the various thyroid cancers.  According to SEER cancer statistics there are approximately 1,950 deaths from thyroid cancer in the United States each year, with about half of these deaths occurring in cases of papillary thyroid cancer. The death rate for thyroid cancer has remained flat even with the rising number of cases. This means that papillary thyroid cancer has an overall five-year survival rate of well over 95%, with even better survival rates for those cases which are considered “low risk” and even “intermediate risk” in the initial phases of diagnosis.  For these patients, survival rates approach  100%  at 20 years.

At first glance, one might assume that these high survival rates are due to medical interventions for thyroid cancer.  However, there is a great deal of research which contends that this is not really the case, given the burgeoning number of diagnoses for low risk disease which according to Gilbert Welch have tripled since 1975.  It is acknowledged that most of the increase is due to the development of ultrasound technology used to detect the disease, or other technology which discovers “incidentalomas” in the course of imaging undertaken for other reasons. Even many specialist who treat thyroid cancer agree that its overdiagnosis is a dilemma which is increasingly being viewed as an ethical problem rather than good medicine.

Not all candidates for overdiagnosed thyroid cancers are NIFTP tumors, although the reclassification of NIFTP should precipitate a fall in the number of thyroid cancers diagnosed in the United States annually.  For this reason, such a change in nomenclature should be welcomed by patients and doctors alike.