Department of Pathology, the First Hospital and College of Basic Medical Sciences, China Medical University, Shenyang.
Department of Pathology, Shenyang 242 Hospital, Shenyang, China.
Medicine (Baltimore). 2021 Apr 16;100(15):e25254. doi: 10.1097/MD.0000000000025254.
Thymic adenocarcinoma is an extremely rare thymic carcinoma. The exact genetic alteration associated with thymic adenocarcinoma is unclear. Here, we report a case of thymic adenocarcinoma accompanied by type A thymoma and pulmonary minimally invasive adenocarcinoma (MIA).
A 53-year-old woman presented with multiple nodules in the mediastinum and lung. Thoracic computed tomography revealed nodules in the anterior superior mediastinum and anterior mediastinum near the right pericardium and ground-glass opacity (GGO) in the right superior lobe of the lung.
The tumor in the anterior superior mediastinum was diagnosed as primary thymic papillary adenocarcinoma. The tumor in the anterior mediastinum near the right pericardium was diagnosed as type A thymoma. The GGO of the right superior lobe of the lung was diagnosed as a MIA.
The patient underwent thoracoscopic mediastinal tumor resection and partial lobectomy in our hospital.
The postoperative course was uneventful. The patient is alive and free of the disease for 22 months after diagnosis.
Thyroid transcription factor 1 (TTF-1) was positive in this case of thymic adenocarcinoma, which indicated that a thymic adenocarcinoma with TTF-1-positive may not necessarily be a metastasis of lung or thyroid adenocarcinoma. The positive staining of CD5 and CD117 can help us to confirm the thymic origin. Molecular genetic analysis indicated that these tumors harbored different mutations. The thymic adenocarcinoma and type A thymoma both had the mutation of KMT2A, but the mutation sites were different. KMT2A mutation may be a common genetic change in thymic tumorigenesis. The genetic alterations disclosed in this study will help expand the understanding of thymic tumors.
胸腺腺癌是一种极为罕见的胸腺癌。与胸腺腺癌相关的确切遗传改变尚不清楚。在这里，我们报告了一例伴有 A 型胸腺瘤和肺微浸润性腺癌（MIA）的胸腺腺癌病例。
一名 53 岁女性因纵隔和肺部多个结节就诊。胸部计算机断层扫描显示前上纵隔和右心包附近前纵隔有结节，以及右肺上叶磨玻璃影（GGO）。
前上纵隔的肿瘤被诊断为原发性胸腺乳头状腺癌。右心包附近前纵隔的肿瘤被诊断为 A 型胸腺瘤。右肺上叶的 GGO 被诊断为 MIA。
患者在我院接受了胸腔镜纵隔肿瘤切除术和部分肺叶切除术。
术后过程顺利。诊断后 22 个月，患者无病生存。
该例胸腺腺癌中甲状腺转录因子 1（TTF-1）阳性，提示 TTF-1 阳性的胸腺腺癌不一定是肺或甲状腺腺癌的转移。CD5 和 CD117 的阳性染色有助于我们确认胸腺起源。分子遗传学分析表明这些肿瘤具有不同的突变。胸腺腺癌和 A 型胸腺瘤均存在 KMT2A 突变，但突变部位不同。KMT2A 突变可能是胸腺肿瘤发生的共同遗传改变。本研究中揭示的遗传改变将有助于扩大对胸腺肿瘤的认识。
