背景 关于自身免疫过程与分化型甲状腺癌（DTC）的临床病理特征及预后之间的潜在关系存在一些争议，而证据受到主要是回顾性的限制。我们使用前瞻性收集的数据，研究了自身免疫性甲状腺炎的存在与一年内甲状腺癌治疗结果之间的关系，采用了大规模多中心研究。方法我们纳入了意大利甲状腺癌观察数据库 (ITCO) (NCT04031339) 中连续登记的DTC患者的数据。我们根据自身免疫性甲状腺炎的存在（AT）或不存在（noAT）将患者分组。我们使用倾向性评分匹配方法比较了两组在一年随访期间的临床特征和治疗结果。结果我们纳入了来自4233名DTC患者的数据，其中3172名（75%）为女性。根据美国甲状腺协会（ATA）的危险度分级，如下：51%（2160/4233）低危、41.3%（1750/4233）中危和7.6%（323/4233）高危。有1552名患者（36.7%）患有自身免疫性甲状腺炎。在倾向性评分匹配之前，AT患者明显年轻，肿瘤较小且双侧（p<0.0001）。AT患者更多地属于低危和中危类别，而noAT患者中ATA高危较多（p=0.004）。在倾向性评分匹配后，与无自身免疫性甲状腺炎的患者相比，有甲状腺炎的患者在疾病证据（结构/生化不完全反应）方面更常见，而出色/不确定反应则较少见（7.3%对4.5%，p=0.001），其OR为1.86（95%可信区间：1.3-2.6，p=0.0001）。然而，当只考虑结构持续性作为结果时，在有或无自身免疫性甲状腺炎的患者之间没有观察到统计学上的显著差异（3.4%对2.7%，p=0.35）。诊断时ATA中危和高危的增加风险仍然保持了统计学上的显著性。结论在这个大规模前瞻性研究中，有自身免疫性甲状腺炎的患者在一年随访期间的生化持续性更常见。然而，自身免疫性甲状腺炎的存在与疾病的结构持续性之间没有明显的关联。这些发现可能可以解释为残余甲状腺组织的存在。

Background There is some controversy on the potential relationship between autoimmune processes and clinicopathological features as well as prognosis of differentiated thyroid cancer (DTC), and the evidence is limited by its largely retrospective nature. We examined the relationship between the presence of autoimmune thyroiditis and 1-year thyroid cancer treatment outcomes in a large, multi-center study, using prospectively collected data. Methods We included data from consecutive DTC patients enrolled in the Italian Thyroid Cancer observatory (ITCO) database (NCT04031339). We divided the groups according to the presence (AT) or absence (noAT) of associated autoimmune thyroiditis. We used propensity score matching to compare the clinical features and outcomes between the 2 groups at 1-year follow-up. Results We included data from 4233 DTC patients, including 3172 (75%) females. The American Thyroid Association (ATA) risk levels were as follows: 51% (2160/4233) low risk, 41.3% (1750/4233) intermediate risk, and 7.6% (323/4233) high risk. There were 1552 patients (36.7%) who had autoimmune thyroiditis. Before propensity score matching, AT patients were significantly younger, and had a smaller and bilateral tumor (p<0.0001). Patients with AT more frequently fell into the low and intermediate risk categories, while ATA high risk was more frequent among noAT patients (p=0.004). After propensity score matching, patients with AT more frequently showed evidence of disease (structural/biochemical incomplete response) versus excellent/indeterminate response, compared to patients without AT (7.3% versus 4.5%, p=0.001), with an OR of 1.86 (95% CI: 1.3-2.6, p=0.0001). However, when considering only structural persistence as the outcome, no statistically significant differences were observed between patients with or without AT (3.4% versus 2.7%, p=0.35). The elevated risk associated with ATA intermediate and high risk at diagnosis remained consistently statistically significant. Conclusions In this large prospective series, biochemical persistence was more frequent, at one-year follow-up, in AT patients. However, there was no significant association between the presence of AT and structural persistence of disease. These findings may be explained by the presence of a residual thyroid tissue.