Papillary thyroid carcinoma: does the association with Hashimoto's thyroiditis affect the clinicopathological characteristics of the disease?

Papillary carcinoma is the most common malignant thyroid neoplasm. The effect of the concurrent presence of Hashimoto's thyroiditis and papillary thyroid carcinoma remains controversial. To evaluate the association between Hashimoto's thyroiditis and clinicopathological parameters in thyroid papillary carcinoma cases, based on an historical institutional cohort analysis. Cross-sectional study obtained from a historical cohort, including all cases submitted to thyroidectomy for papillary thyroid carcinoma in a single institution during an 11-year period study. A total of 417 patients with papillary thyroid carcinoma were enrolled; 148 (35.4%) also had Hashimoto's thyroiditis. A female predominance among cases associated to Hashimoto's thyroiditis was observed. The thyroid tumor, in cases associated with Hashimoto's thyroiditis, had a smaller mean diameter, lower frequency of extra-thyroid extension, and earlier clinicopathological staging. A high proportion of papillary thyroid carcinoma cases are associated with Hashimoto's thyroiditis. There are associations among these cases with several histopathological factors already recognized for their prognostic value, which by themselves could impact outcomes. O carcinoma papilífero é a neoplasia maligna mais comum da tireóide. O efeito da coexistência da tireoidite de Hashimoto (TH) no prognóstico do carcinoma papilífero da tireóide (CPT) permanece controverso. Avaliar a associação entre TH e parâmetros clínico-patológicos entre pacientes com diagnóstico de carcinoma papilífero da tireóide obtidos através da análise de uma série histórica institucional. Coorte transversal com base em uma coorte histórica, envolvendo todos os casos submetidos à tireoidectomia total por motivo de carcinoma papilífero, realizadas na mesma Instituição ao longo de 11 anos. Um total de 417 pacientes foram incluídos no estudo, estando 148 (35,4%) associados à TH. Observamos preponderância de mulheres entre os casos associados à TH. Esses casos se apresentaram com menor média de diâmetro tumoral, menor frequência de comprometimento extra-tireoidiano e estadiamento clínico-patológico mais precoce. Um percentual expressivo de casos de CPT apresenta-se associado à TH. A associação entre esses casos, com vários fatores histopatológicos já reconhecidos por seu valor prognóstico, pode por sí só influenciar no desfecho desses pacientes.