Thyroid Cancer Guidelines Still Make Sense

Thyroid cancer diagnosis using genetic mutations is valuable

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Sometimes the quick march of molecular science leaves behind the clinical world, with rapid advances in laboratory work taking time to filter through journals and into use.

Following the publication of guidelines in 2006, a flurry of advances in molecular biology research resulted in the American Thyroid Association having to quickly draft a new set of rules in 2009.

"Ask your oncologist about their diagnostic guidelines."

A recent study by a team from Quest Diagnostics in California evaluated recent biopsies in their laboratory and concluded that laboratory testing based on the guidelines may help to identify genetic mutations associated with a higher risk of thyroid cancer.

First author of the study, and senior scientist at Quest Diagnostics, Shih-Min Cheng, PhD, stated that stated that identifying the markers may help clinicians identify patients whose thyroids are cancerous and require surgical removal while sparing patients at low risk of cancer from unnecessary removal of healthy thyroids.

Biopsies are done with a technique called fine needle aspiration, which delicately removes cells from the patient's thyroid and transports them for analysis to the laboratory.

The full evaluation for thyroid cancer takes place in two parts, with examination of the cells using a microscope and staining techniques, and a full series of tests looking for molecular evidence of genetic changes.

Consistent with the 2009 guidelines by the American Thyroid Association, the study found that out of 149 thyroid cancer biopsies, follicular thyroid cancer involved mutations in the RAS and PAS8/PPARy genes in about half of the tested specimens, suggesting that testing for the mutations may help identify patients with this common form of thyroid cancer.

Papillary thyroid cancer, on the other hand, commonly involved mutations in the BRAF, RAS genes, and RET/PTC genes, but never the PAS8/PPARy gene.

Follicular adenomas of the thyroid only involved RAS mutations.

The guidelines were well regarded following publication in 2009 owing to heavy use of data provided by pathology laboratories detailing microscopic qualities, as well as taking into account the different, unique genetic mutations involved in each category of thyroid cancer.

"Nobody should underestimate the danger of badly managed thyroid cancer, and this American Thyroid Association Task Force has produced a first class guide for practitioners," stated Terry Davies, MD, the President of the American Thyroid Association at the time.

Studies presented at conferences as well as their conclusions should be considered preliminary findings until publication in a peer-reviewed journal.

The research was funded by Quest Diagnostics.

Reviewed by: 
Review Date: 
June 15, 2012
Last Updated:
June 20, 2012