1 内蒙古医科大学基础医学院病理学教研室，呼和浩特 010059
2 内蒙古医科大学附属医院病理科，呼和浩特 010059
目的：探讨胸腺上皮性肿瘤组织学分型特点及其对临床的指导作用。方法：按照世界卫生组织(World Health Organization，WHO)2015年胸腺上皮性肿瘤组织学分型标准对63例胸腺上皮性肿瘤分类并进行回顾性分析，使用卡方检验分析WHO组织学分型和Masaoka临床分期之间的关系。结果：根据WHO(2015)诊断标准对63例胸腺上皮性肿瘤进行组织学分型，A、AB、B1、B2、B3胸腺瘤分别有4例(6.35%)、15例(23.81%)、15例(23.81%)、16例(25.40%)和5例(7.93%)，化生性胸腺瘤2例(3.17%)，微结节性胸腺瘤伴淋巴样间质3例(4.76%)，胸腺癌3例(4.76%)，其中2例为鳞状细胞癌，1例为不典型类癌。63例胸腺上皮性肿瘤中19例伴有重症肌无力(myasthenia gravis，MG)。所有患者的影像学均表现为纵隔占位。依照Masaoka临床分期，63例患者中I期20例、II期24例、III期13例、IV期6例。卡方检验结果示组织学分型与临床分期之间有一定的相关性(P<0.05)，组织学分型靠后的胸腺上皮性肿瘤其Masaoka临床分期也较高。41例获5~47个月的随访，4例死亡。1例因胸腺瘤引发的MG而死亡，组织分型为B3型，Masaoka临床分期为III期。1例死因不明，组织分型为B2型，Masaoka分期为II期。另2例死于胸腺鳞状细胞癌，Masaoka临床分期为IV期。结论：不同组织学类型胸腺上皮性肿瘤的组织病理学形态各具特点；结合患者临床症状、胸部影像学检查、病理组织学形态改变及免疫组织化学染色可对胸腺上皮性肿瘤进行诊断和鉴别诊断；WHO组织学分型可帮助评估胸腺上皮性肿瘤的生物学行为并指导肿瘤治疗。
Retrospective analysis of the results of WHO tissue typing in 63 cases of thymic epithelial tumors
CorrespondingAuthor: XU Xiaoyan
This work was supported by the Natural Science Foundation of Inner Mongolia Autonomous Region, China (2019MS08115).
Objective: To investigate the histological characteristics of thymic epithelial tumors and its clinical guidance. Methods: According to World Health Organization (WHO) 2015 thymic epithelial histological classification criteria, 63 cases of thymic epithelial tumors were classified and retrospectively analyzed and Chi-square test was used to analyze the relationship between WHO histological classification and Masaoka clinical stage. Results: According to WHO (2015) diagnostic criteria, 63 cases of thymic epithelial tumors were classified. The histological classifications of A, AB, B1, B2, and B3 were 4 cases (6.35%), 15 cases (23.81%), 15 cases (23.81%), 16 cases (25.40%) and 5 cases (7.93%), respectively; there are 2 cases (3.17%) of metaplastic thymoma, 3 cases (4.76%) of micronodular thymoma with lymphoid interstitial. And there were 3 cases (4.76%) of thymic carcinoma, 2 of which were squamous cell carcinoma, and 1 of which was atypical carcinoid. Nineteen of the 63 thymic epithelial tumors were associated with myasthenia gravis (MG). The imaging findings were all mediastinal placeholders. According to Masaoka staging, 20 of the 63 patients were in stage I, 24 were in stage II, 13 were in stage III, and 6 were in stage IV. Chi-square test results showed that there was a correlation between histological type and clinical stage (P<0.05). Thymic epithelial tumors with latter histological types also had higher Masaoka clinical stages. Forty-one patients were followed up for 5–47 months, and 4 patients died. One patient died of MG due to thymoma. The histological type was B3 and the Masaoka stage was stage III. The cause of death was unknown in one case. And its histological classification was B2, and the Masaoka stage was stage II. The other 2 patients died of thymic squamous cell carcinoma, with Masaoka stage IV. Conclusion: Each type of thymic epithelial tumor has its own characteristics in histopathology; combined with patients’ clinical symptoms, chest imaging examination, histopathological morphological changes and immunohistochemical staining, thymic epithelial tumors can be diagnosed and differentially diagnosed; WHO histological classification can help assess the biological behavior of thymic epithelial tumors and guide tumor treatment.
thymic epithelial tumor; Masaoka staging; histological typing; pathological characteristics; prognosis