Put Down That Surgical Knife

Thyroid cancer detection methods may no longer require surgery

(RxWiki News) Who wants to have part of their thyroid removed if they don’t actually have cancer? The good news is that the knives may be going away when it comes to diagnosing cancer in the future.

A recent study found biomarkers on genes that indicate thyroid cancer from a needle sample of tissue.

This means a simple procedure can extract biomarkers from your body which can show that a disease may be present, or not.

"Ask your doctor about new thyroid tests."

Chiara Mazzanti, PhD, and Sarah Tomei, PhD, from the Section of Molecular Pathology at the Pisa University Hospital in Pisa, Italy, led the investigation.

Approximately 50 percent of all people have thyroid nodules, but 90 percent or more of the nodules are non-cancerous or benign.

If a doctor detects a thyroid nodule, the standard procedure is to do what’s called a fine needle aspiration (FNA) biopsy to see if the nodules are cancerous or malignent.

FNAs are minimally invasive. A hollow needle is injected into the thyroid nodule to ‘grab’ a small sample, and that’s it.

The problem is, about 30 percent of these FNA samples don’t provide enough information to diagnose cancer. When this happens, patients must undergo surgery to have a portion of the thyroid removed for further diagnostic tests.

The kicker is that only 20 percent of those cases actually have cancerous thyroid nodules - meaning 80 percent of people who undergo a partial thyroid removal to test for cancer don’t actually have it!

Dr. Mazzanti’s research team discovered a new way to read the initial FNA sample that could eliminate the need for surgery altogether.

They tested the genetic makeup of 93 different FNA samples.

The result was eight different biomarkers on eight specific genes that could consistently tell the difference between malignant and benign tumors 89 percent of the time. 

The genes in question were KIT, CDH1, LSM7, C21orf4, DDI2, TC1, Hs.296031 and BRAF.

Dr. Tomei said, “Almost half of all the malignant samples, but none of the benign samples, carried the V600E mutation in the gene BRAF. We would recommend that a sample with unclear cytology which contains this mutation be treated as malignant.”

“The gene with the highest predictive power was KIT. KIT activity is turned down in thyroid cancer, so BRAF-normal samples, with low levels of KIT, should also be treated as suspected cancer.”

Authors said they hoped this genetic testing approach would reduce unnecessary thyroid removal by around 50 percent, while also accurately pinpointing cancers that need to be treated.

This study was published in September in BMC Cancer. No funding information was provided and no conflicts of interest were reported.

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Review Date: 
September 7, 2012