Study of the histological profile of papillary thyroid carcinomas associated with Hashimoto's thyroiditis

OBJECTIVE: To investigate the association between the histological parameters of papillary thyroid cancer (PTC) and the presence of Hashimoto's thyroiditis (HT). MATERIALS AND METHODS: Histological samples from patients with PTC were reviewed by an endocrine pathologist. The following parameters were analyzed: presence of concomitant HT, multifocality, presence of nodal metastasis, tumor size, vascular invasion, perineural infiltration, histological variant, and pathological staging. Clinical data included gender and age at the time of the diagnosis. RESULTS: A total of 94 cases of PTC were reviewed. There was a predominance of women (85.1% vs. 14.9%) and median age at presentation was 45.13 years. The presence of HT was significantly associated with greater occurrence of multifocal tumors (p = 0.004), early pathological stage (p = 0.02), and smaller tumor size (p = 0.025). CONCLUSIONS: Patients with PTC associated with HT had significantly smaller tumors, more often multifocal and in an earlier stage than their counterparts without HT. A better understanding of the immune response involved in these tumors may be useful for future strategies on the prevention and for the development of new therapeutic approaches for this group of neoplasms.