BACKGROUND Whether differentiated thyroid cancer (DTC) occurring concomitantly with Graves' disease (GD) is more aggressive and bound to a less favorable outcome is controversial. OBJECTIVE Aim of this multicenter retrospective study was to compare baseline features and outcome of DTC patients with GD (DTC/GD+) or without GD (DTC/GD-). PATIENTS Enrolled in this study were 579 patients referred to five endocrine units (Cagliari, Pavia, Pisa, Siena, and Varese) between 2005 and 2014: 193 patients had DTC/GD+ , 386 DTC/GD-. Patients were matched for age, gender and tumor size. They underwent surgery because of malignancy, large goiter size, or relapse of hyperthyroidism in GD. RESULTS Baseline DTC features (histology, lymph node metastases, extrathyroidal extension) did not differ in the two groups, except for multifocality which was significantly more frequent in DTC/GD+ (27.5% vs. 7.5%, p < 0.0001). At the end of follow-up (median 7.5 years), 86% of DTC/GD+ and 89.6% DTC/GD- patients were free of disease. Patients with persistent or recurrent disease (PRD) had "biochemical disease" in the majority of cases. Microcarcinomas were more frequent in the DTC/GD+ group (60% vs. 37%, p < 0.0001) and had an excellent outcome, with no difference in PRD between groups. However, in carcinomas ≥ 1 cm, PRD was significantly more common in DTC/GD+ (24.4% vs. 11.5%; p = 0.005). In the whole group, univariate and multivariate analyses showed that GD+ , lymph node involvement, extrathyroidal invasion, multifocality and tall cell histotype were associated with a worse outcome. Female gender and microcarcinomas were favorable features. No association was found between baseline TSH-receptor antibody levels and outcome. Graves' orbitopathy (GO) seemed to be associated with a better outcome of DTC, possibly because patients with GO may early undergo surgery for hyperthyroidism. CONCLUSIONS GD may be associated with a worse outcome of coexisting DTC only if cancer is ≥ 1 cm, whereas clinical outcome of microcarcinomas is not related to the presence/absence of GD.

中文翻译：

---

与Graves病相关的分化型甲状腺癌的特征和结局：一项大型回顾性多中心研究的结果。

背景技术与格雷夫斯氏病（GD）并发的分化型甲状腺癌（DTC）是否更具侵略性，且结局较差。这项多中心回顾性研究的目的是比较患有GD（DTC / GD +）或不患有GD（DTC / GD-）的DTC患者的基线特征和预后。患者2005年至2014年间，有579名患者被分为五个内分泌单位（卡利亚里，帕维亚，比萨，锡耶纳和瓦雷泽），其中193例患者患有DTC / GD +，386例DTC / GD-。根据年龄，性别和肿瘤大小对患者进行匹配。他们因恶性肿瘤，大甲状腺肿或GD甲状腺功能亢进复发而接受了手术。结果两组的基线DTC特征（组织学，淋巴结转移，甲状腺外扩展）无差异，除了在DTC / GD +中更加频繁的多焦点外（27.5％对7.5％，p <0.0001）。在随访结束时（中位7.5年），DTC / GD +患者中的86％和DTC / GD-患者中的89.6％没有疾病。在大多数情况下，患有持续性或复发性疾病（PRD）的患者患有“生化疾病”。DTC / GD +组微癌的发生率更高（60％vs. 37％，p <0.0001），并且结局极好，两组之间的PRD无差异。然而，在≥1 cm的癌中，PRD在DTC / GD +中更为常见（24.4％对11.5％； p = 0.005）。在整个组中，单因素和多因素分析表明GD +，淋巴结受累，甲状腺外侵犯，多灶性和高细胞组织型与较差的结局相关。女性和微癌是有利的特征。在基线TSH-受体抗体水平和预后之间未发现关联。Graves眼病（GO）似乎与DTC的预后更好有关，可能是因为GO患者可能会早期接受甲状腺功能亢进手术。结论仅在癌症≥1 cm的情况下，GD可能与更严重的DTC共存相关，而微癌的临床结局与GD的存在与否无关。