分析原发性胸腺癌的临床表现及MSCT诊断意义。

回顾性分析经病理确诊的43例胸腺癌患者的临床和影像资料，CT图像分析：肿块位置、形态、大小、边缘、密度、强化程度、肿块与邻近组织器官的关系、心包/胸腔积液、纵隔淋巴结肿大及远处转移情况。

原发性胸腺癌好发于中老年人，平均年龄为(55.3±13.0)岁，男性较女性多见(2.91︰1)；主要临床症状为胸痛、胸闷，其次为气促、咳嗽。43例软组织肿块位于前纵隔，38例呈偏侧性生长，5例沿中线向两侧生长，肿块形态不规则，边界不清，呈浸润性生长，最大径为3.8~13 cm，平均(7.2±3.5)cm；平扫肿块呈软组织密度影，CT值(32.3±10.7)Hu；密度较均匀4例(2.3%，4/43)；密度不均匀39例(97.7%)，其内见斑片状坏死/囊变；17例病灶内见钙化灶。肿块-心脏大血管界面征阳性42例；肿块-肺界面征阳性13例；合并心包/胸腔积液29例；伴纵隔淋巴结肿大25例；伴远处转移12例。增强扫描肿块以中度强化为主，囊变坏死区无强化，动脉期及静脉期CT值分别为(58.2±16.1)Hu、(64.0±18.6)Hu。

原发性胸腺癌是一种相对罕见的纵隔恶性肿瘤，临床症状缺乏特异性。MSCT表现具有一定的特征，主要表现为前纵隔偏侧生长的不规则软组织肿块，密度不均匀，增强以中度强化为主，肿块常侵犯邻近组织器官。MSCT不仅能够显示肿瘤的内部结构，还能显示与邻近结构的关系，对术前正确诊断及临床治疗方案的选择具有重要的临床意义。

To investigate the clinical features and CT findings of thymic carcinoma.

The clinical features and imaging of 43 patients with thymoma carcinoma confirmed by pathology were retrospectively analyzed, by studying the tumor location, shape, size, edge, density, enhancement mode, relationship between tumor and adjacent tissues and organs, pericardial /pleural effusion, lymph node /distant metastasis on CT.

The primary thymic carcinoma was more common in the middle-aged and elderly, with an average age of (55.3 ± 13.0) years. The main clinical symptoms were chest pain and chest tightness, followed by shortness of breath and cough. Male is more common than female(2.91︰1). The location of all the irregular tumor were located in the anterior mediastinum, include lateral growth was found in 38 cases and median growth in 5 cases. The maximum diameter of the mass was 3.8~13 cm, The average size was (7.2±3.5) cm. All the tumors were invasive growth, the boundary was not clear, and the surrounding fat space disappeared and blurred. The average CT value on plain scan was(32.3±10.7)Hu. On the plain scan, the density of the mass was not uniform in 39 cases, and uniform in 4 case. Patchy necrosis are seen in most lesions. Calcification was found in 17 cases. Tumors encircling macrovasular or pericardium were found in 42 cases, invaded the lung tissue were found in 13 cases, and pericardial /pleural effusion were found in 29 cases. There were 25 cases with lymph node metastasis in mediastinum and 12 case with distant metastases. On the contrast-enhanced scan, the solid part of tumor almost showed moderately enhancement, and the necrosis in the mass showed no enhancement. The mean CT value of the arterial phase and venous phase was about (58.2±16.1)Hu and(64.0±18.6)Hu, respectively.

The thymic carcinoma is a rare mediastinal malignant tumor with no special symptom. The main manifestations were irregular soft tissue mass growing laterally in the anterior mediastinum with uneven density on CT. The enhancement was mainly moderately enhanced. The mass often invaded adjacent tissues and organs. Multi slice spiral CT has certain characteristics, which can not only show the internal structure of the tumor, but also show the relationship with adjacent structures. It is of great significance for the correct preoperative diagnosis and the choice of clinical treatment.