Recent research has found that age-associated risk in papillary thyroid cancer is dependent on BRAF V600E or wild-type status, published in the Journal of Clinical Oncology (online December 14, 2017; doi:10.1200/JCO.2017.74.5497).
Patient age at diagnosis has been used regularly as a mortality risk factor in papillary thyroid cancer for the past 65 years. However, whether age at diagnosis is applicable in patients with different BRAF genetic backgrounds remains unclear.
Xiaopei Shen, PhD, Johns Hopkins University School of Medicine, and colleagues conducted a comparative study of the relationship between patient age at diagnosis and papillary thyroid cancer-specific mortality with respect to BRAF status. A total of 2638 patients were enrolled with a median age of 46 years at diagnosis. Patients were sampled from 11 medical centers in six countries.
Results of the study showed a linear association between patient age and mortality in those with BRAF V600E mutation. However, the same association did not exist for patients with wild-type BRAF; in such patients, the mortality rate remained low and flat with increasing age.
Similarly, Kaplan-Meier survival curves showed a rapid decline with increasing age in patients with BRAF V600E mutation, but no decline in patients with wild-type disease, even in those aged 75 years or older.
Researchers acknowledged that the association between mortality and age in patients with BRAF V600E was independent of clinicopathologic risk factors. Additionally, results were similar when analyzing patients with the conventional variant of papillary thyroid cancer.
Dr Shen and colleagues concluded that age-associated mortality risk in papillary thyroid cancer is dependent on BRAF status. Age is a strong mortality risk factor only in patients with BRAF V600E mutation. “These results question the conventional general use of patient age as a high-risk factor in papillary thyroid cancer and call for differentiation between patients with BRAF V600E and wild-type BRAF when applying age to risk stratification and management of papillary thyroid cancer,” they wrote.—Zachary Bessette