Objective: The objective was to evaluate the clinical behavior and outcome of 202 papillary thyroid cancers in Graves’ disease patients during the period 1994–2004.
Design: This was a retrospective, non-randomized case–control study.
Methods: Since 1994, we have included an ultrasonogram of the neck in the initial examination of thyroid disease patients who consult our outpatient clinic. We evaluated the tumor status and long-term outcome of Graves’ disease patients with thyroid cancer and of age- and tumor size-matched euthyroid papillary thyroid cancer patients as controls. Serum TSH receptor antibody (TRAb) was measured in the Graves’ disease group.
Results: A total of 154 papillary thyroid cancers were diagnosed in the Graves’ disease patients and were treated surgically. At surgery, no significant differences in multifocality, lymph node metastasis, or distant metastasis were found between the Graves’ disease group and the euthyroid group. On the whole, the clinical course of the cancers in both the Graves’ disease group and euthyroid group was relatively good. No significant correlations were found between the TRAb levels in the Graves’ disease group and multifocality or the presence of lymph node metastasis. Papillary thyroid cancer was discovered as an incidental finding in 2% of the 2356 surgically treated Graves’ disease patients, but none of them developed metastasis during the follow-up period.
Conclusion: The results in this series of patients do not support the claim that thyroid cancer is more aggressive in Graves’ disease patients than in euthyroid patients.