Preoperative BRAF mutation found to be a risk for extensive disease in papillary thyroid cancer

Preoperative BRAF mutation testing of fine-needle aspiration biopsy specimens in patients with papillary thyroid cancer may help to identify those who are at an increased risk for extensive disease — including extrathyroidal extension and lymph node metastases — and those who are at the highest risk for disease persistence or recurrence.

Researchers demonstrated that BRAF mutation testing of fine-needle aspiration biopsy specimens may be a novel tool in determining preoperative risk stratification in patients with papillary thyroid cancer. They said this tool may be a “powerful risk prognostic marker” and could be used to better tailor the initial surgical extent for patients with papillary thyroid cancer.

The researchers examined the T1799A BRAF mutation status in fine-needle aspiration biopsy specimens of the thyroid in 190 patients prior to undergoing a thyroidectomy. The researchers examined papillary thyroid cancer and its association with clinicopathologic characteristics of the tumor that were revealed postoperatively.

The findings indicated that patients who had the BRAF mutation were significantly more likely to have poorer clinicopathologic outcomes related to papillary thyroid cancer.

In comparison with the wild-type allele, patients with the BRAF mutation were significantly more likely to have extrathyroidal extension (23% vs. 11%), thyroid capsular invasion (29% vs. 16%) and lymph node metastasis (38% vs. 18%).

Follow-up data indicated the risk for persistence and recurrence of papillary thyroid cancer. These data indicated that during a median of three years, patients with the BRAF mutation had a 36% chance of persistence or recurrence; those without the BRAF mutation had a 12% chance. – by Jason Harris

BRAF mutation is the most recent advance as a more reliable indicator in predicting the potential aggressiveness of papillary thyroid carcinoma. At the present time there is no uniformity of opinion amongst thyroid surgeons concerning the extent of surgery required for patients with papillary thyroid carcinoma. Testing for BRAF mutation, which can be readily performed on fine-needle aspiration biopsy specimens, will possibly indicate the need for additional preoperative evaluation for lymph node metastases and preparation for more extensive surgery.

– Mark Persky, MD

HemOnc Today Editorial Board member

Xing M. J Clin Oncol. 2009;doi:10.1200/JCO.2008.20.1426.