Familial history of non-medullary thyroid cancer is an independent prognostic factor for tumor recurrence in younger patients with conventional papillary thyroid carcinoma.

Background: It is not clear whether familial non-medullary thyroid cancer (FNMTC) is more aggressive and has a poorer prognosis, than sporadic carcinoma. Therefore, the optimal clinical approach for FNMTC is yet to be established. In this study, we investigated the biological behavior and prognosis of FNMTC compared with its sporadic counterpart.

Methods: Between 1996 and 2004, 1,262 patients underwent a total thyroidectomy for conventional PTC at Asan Medical Center and 113 (9.0%) were diagnosed with FNMTC. We compared the clinico-pathologic characteristics, treatment modalities, and prognosis between familial and sporadic NMTC.

Results: FNMTC was significantly more multi-centric than sporadic. We also found that family history itself was an independent risk factor for recurrence. Moreover, disease-free survival in the familial group was significantly shorter than in the sporadic group in the subgroups in which age was <45 years, and in which the tumors were multi-centric, bilateral, and of N1b node status.

Conclusion: FNMTC may be considered as a separate clinical entity with a higher rate of recurrence and worse DFS than its sporadic counterpart. Furthermore, familial history of NMTC is an independent risk factor for recurrence, especially in younger patients with conventional PTC.