Department of Pathology, Louis-Pradel Hospital, Hospices Civils de Lyon, Lyon, France.
Department of Respiratory Medicine, National Expert Centre for Thymic Malignancies, Cancer Institute of the Hospices Civils de Lyon, Louis-Pradel Hospital, Lyon, France; Lyon University, Claude Bernard Lyon-1 University, Lyon, France.
J Thorac Oncol. 2017 Oct;12(10):1571-1581. doi: 10.1016/j.jtho.2017.06.072. Epub 2017 Jul 8.
Thymic epithelial tumors (TETs) are rare intrathoracic malignancies that are categorized histologically according to the WHO classification, which was recently updated in 2015 on the basis of a consensus statement of the International Thymic Malignancy Interest Group (ITMIG); at the same time, the standard Masaoka-Koga staging system is scheduled to be replaced by the eighth edition of the TNM staging classification by the American Joint Committee on Cancer/Union for International Cancer Control consortium. Our objectives were to analyze the feasibility of assessing ITMIG consensus major and minor morphological and immunohistochemical criteria and the eighth edition of the TNM staging classification in a routine practice setting.
This is a single-center study conducted at the Louis-Pradel Hospital of Lyon University, one of the largest centers for TETs in France. Overall, a large surgical series of 188 TETs diagnosed in 181 patients between 2000 and 2014 at our center were analyzed.
There were 89 men (49%) and 92 women (51%); 57 patients (31%) presented with myasthenia gravis at time of diagnosis. According to the WHO classification, there were nine type A thymomas (5%), 67 type AB thymomas (36%), 19 type B1 thymomas (10%), 46 type B2 thymomas (24%), 27 type B3 thymomas (14%), and 20 thymic carcinomas (11%). ITMIG consensus major criteria were identified in 100% of type A, AB, B1, and B2 thymomas. After restaging according to the eighth edition of the TNM staging classification, there were 127 stage I (84%), three stage II (2%), 17 stage IIIa (11%), no stage IIIb, two stage IVa (1%), and three stage IVb (2%) thymomas. Significant correlation between histological type and stage at diagnosis was maintained after restaging according the TNM classification.
Comprehensive analysis of our well-characterized surgical series of 188 TETs indicates the feasibility and the diagnostic value of the ITMIG consensus statement on WHO histological classification and highlights the major switch in staging when the eighth edition of the TNM staging classification is applied.
胸腺瘤（TET）是一种罕见的胸腔内恶性肿瘤，根据世界卫生组织（WHO）分类进行组织学分类，该分类最近在 2015 年基于国际胸腺癌兴趣小组（ITMIG）的共识声明进行了更新；同时，标准的 Masaoka-Koga 分期系统将被美国癌症联合委员会/国际癌症控制联盟联合会的第八版 TNM 分期分类取代。我们的目的是分析在常规实践中评估 ITMIG 共识主要和次要形态学和免疫组织化学标准以及第八版 TNM 分期分类的可行性。
这是在里昂大学路易斯-普拉德尔医院进行的一项单中心研究，该医院是法国最大的 TET 中心之一。总体而言，分析了 2000 年至 2014 年期间在我们中心诊断的 181 例患者的 188 例 TET 大型手术系列。
男性 89 例（49%），女性 92 例（51%）；57 例患者（31%）在诊断时患有重症肌无力。根据 WHO 分类，有 9 例 A 型胸腺瘤（5%）、67 例 AB 型胸腺瘤（36%）、19 例 B1 型胸腺瘤（10%）、46 例 B2 型胸腺瘤（24%）、27 例 B3 型胸腺瘤（14%）和 20 例胸腺癌（11%）。100%的 A 型、AB 型、B1 型和 B2 型胸腺瘤均符合 ITMIG 共识主要标准。根据第八版 TNM 分期分类重新分期后，I 期 127 例（84%）、II 期 3 例（2%）、IIIa 期 17 例（11%）、无 IIIb 期、IVa 期 2 例（1%）和 IVb 期 3 例（2%）。根据 TNM 分类重新分期后，组织学类型与诊断时的分期之间仍保持显著相关性。
对我们特征明确的 188 例 TET 手术系列的综合分析表明，ITMIG 关于 WHO 组织学分类的共识声明具有可行性和诊断价值，并突出了第八版 TNM 分期分类应用时分期的主要转变。
