Comparison of clinical and histopathological characteristics of differentiated thyroid cancers in euthyroid nodular goiter and Graves' disease.

Background: Graves' disease (GD) is characterized by autoimmune hyperthyroidism. Its association with papillary thyroid carcinoma (PTC) remains controversial, with conflicting data regarding tumor aggressiveness and clinical outcomes.

Objective: To compare the clinical and histopathological features of PTC in patients with GD versus those with euthyroid nodular goiter.

Methods: A retrospective review was conducted on 995 patients who underwent thyroidectomy for PTC between 2014 and 2023. Group 1 included 59 patients with GD and coexisting PTC, while group 2 comprised 936 euthyroid patients with PTC. Tumor characteristics, recurrence rates, and treatment outcomes were analyzed.

Results: PTCs in the GD group were more frequently papillary microcarcinomas (85 vs 43%, P < 0.001) and exhibited significantly lower rates of multicentricity, vascular invasion, and lymph node metastasis. There were no statistically significant differences in recurrence or distant metastasis between groups. Multivariate analysis identified older age and the presence of thyroid nodules as independent predictors of PTC in patients with GD.

Conclusion: PTC associated with GD appears to exhibit more favorable histopathological features. However, the risk of malignancy increases with age and ultrasonographically detected nodules in GD patients. These findings support the importance of vigilant surveillance and individualized treatment planning in this population.