Researchers Redefine One Variant as Not Thyroid Cancer If It’s Not Invasive

A 29-member international research panel has concluded that some thyroid tumors are not cancer if they are a variant called “encapsulated follicular variant of papillary thyroid cancer” (EFVPTC) and if they do not have any capsular or vascular invasion. The panel proposed that these tumors be renamed “noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP).”

Their study is presented in the Journal of the American Medical Association (JAMA) Oncology, and described in the April 14, 2015, New York Times. Yuri Nikiforov, M.D., the lead author, is vice chairman of pathology at the University of Pittsburgh Medical Center. Dr. Nikiforov is a ThyCa Medical Advisor.

The researchers note that this reclassification does not apply to all tumors of this variant. Some of the tumors are cancer, because they have capsular invasion, vascular invasion, or both.

Here are a few of the questions raised in the last few days in ThyCa local support groups, online groups, and e-mails, plus information based on the two articles linked above. If you have any questions about your diagnosis and/or care after reading this article, we encourage you to consult with your physician.

1. Does this reclassification apply to every thyroid tumor that is encapsulated follicular variant of papillary thyroid cancer (EFVPTC)?
     
   No. This reclassification is specifically only for EFVPTC with no invasion. The researchers concluded that this reclassification does not include invasive EFVTPC.
      
2. Does surgery need to be done?
     
   Yes, at least the part of the thyroid that contains the tumor needs to be removed so that the pathologist can examine the tissue to determine whether the tumor is completely surrounded by a capsule of fibrous tissue and whether there is capsular or vascular invasion. The results of the tissue analysis will determine whether there is invasion, and, therefore, whether the reclassification applies.
     
3. Will a patient with a noninvasive tumor of this variant need further treatment after the surgery?
     
   The articles note that patients whose tumors will be classified as not cancer will not need further surgery such as a completion thyroidectomy, and will not require radioactive iodine (RAI). All the patients in the study who fit the criteria for reclassification were free of disease during the entire follow-up period of from 10 to 26 years after their initial surgery. None received RAI.
     
4. What will be the follow-up over the long term?
     
   The articles focus on the reclassification rather than on overall long-term care. Individuals should consult with their own physician regarding their care.
    
   As noted in earlier articles in this Bulletin, during regular medical and dental appointments, ThyCa encourages neck checks to find thyroid nodules. According to the Academy of General Dentistry, brief head and neck evaluations are a standard of care for dental appointments.
     
5. Do these findings apply to all papillary thyroid cancer?
    
   No. The reclassification does not apply to most papillary thyroid cancer. It applies only to encapsulated follicular variant of papillary thyroid cancer (EFVPTC), and only to noninvasive EFVPTC, not all EFVPTC. From the articles, the reclassification applies to about 10,000 of the 64,300 people expected to be diagnosed with thyroid cancer in the United States in 2016.
     
6. Is this new classification official?
    
   The authors of the medical journal article proposed this reclassification and the new name. An editorial in the same issue of the journal also recommends renaming these tumors. The New York Times article says that “eight leading professional societies from around the world signed on to the declassification and to the new name.”

The eight societies are the American Academy of Otolaryngology Head and Neck Surgery, American Head and Neck Society, Brazilian Society of Endocrinology and Metabolism, Brazilian Society of Head and Neck Surgery, British Association of Endocrine and Thyroid Surgeons, International Neural Monitoring Study Group, Japanese Thyroid Association, Latin American Thyroid Association, and World Congress on Thyroid Cancer.

The researchers have also submitted an editorial about this research to Thyroid, the journal of the American Thyroid Association.

ThyCa’s web site and future issues of this newsletter will add more information about this topic.

Do you have questions? If so, please e-mail to publications@thyca.org.