Family History Correlates with More Aggressive Variants of Papillary Thyroid Cancer

Background: Papillary thyroid cancer (PTC) generally occurs sporadically but about 5% of cases are familial in origin. Furthermore, family history has been established as an influential risk factor for PTC. This study determines whether patients with a family history of thyroid cancer harbor more aggressive variants of PTC. Materials and Methods: A retrospective review of prospectively collected data of 1779 consecutive patients who underwent thyroidectomy was performed. Patients were divided into patients who had a history of PTC in first degree relatives (n=39) and those that did not (n=1740). Patients with PTC on final pathology were further subdivided into those with less aggressive (classic and follicular) and patients with more aggressive (diffuse sclerosing and tall cell) variants of PTC. A two tailed Z test at a significance level of p<0.05 was used to compare groups. Results: Of 1779 patients included, 39 (2.2%) had a family history of PTC. Of patients with a positive family history, 20 (51.2%) had PTC on final pathology. Furthermore, these patients had a significantly increased incidence of more aggressive variants of PTC at 15.4% (6/39) compared to patients with no family history of PTC at 2.7% (47/1740) (p<0.05). Conclusions: Patients with a positive family history of PTC have a significantly higher incidence of more aggressive PTC variants. A positive PTC family history, therefore, should be considered a risk factor for its more aggressive variants that may necessitate earlier recognition and treatment for these patients and their affected family members.