Weissferdt Annikka
Department of Anatomic Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Mediastinum. 2023 Apr 12;7:25. doi: 10.21037/med-22-50. eCollection 2023.
Spindle cell thymomas are the most common spindle cell neoplasms of the anterior mediastinum. These tumors belong to the group of thymic epithelial neoplasms and are known for their wide histomorphologic spectrum. This histological heterogeneity is the reason why unequivocal diagnosis can be challenging, especially when dealing with small biopsy material. Conversely, less conventional patterns of the tumor may also pose significant diagnostic problems in resected material and the differential diagnosis often includes other spindle cell neoplasms that are known to arise in the mediastinal cavity. These can be of variable origin and may share overlapping pathological features with spindle cell thymoma. Since spindle cell thymomas are tumors that primarily affect the adult population and predominantly arise from the thymic gland in the anterior mediastinum, this review will focus on the differential diagnosis with other spindle cell neoplasms that share similar demographic characteristics and, for the most part, originate from the anterior mediastinal compartment. These include other epithelial spindle cell tumors of thymic origin (sarcomatoid thymic carcinoma and spindle cell carcinoid tumor), mesenchymal neoplasms [solitary fibrous tumor (SFT), synovial sarcoma, and dedifferentiated liposarcoma] and various other tumors with spindle cell morphology, that may occasionally involve the anterior mediastinum. The clinical, pathological, immunohistochemical and molecular hallmarks of these lesions will be discussed and useful tips for the differential diagnosis with spindle cell thymoma will be provided.
梭形细胞胸腺瘤是前纵隔最常见的梭形细胞肿瘤。这些肿瘤属于胸腺上皮性肿瘤，以其广泛的组织形态学谱而闻名。这种组织学异质性是明确诊断具有挑战性的原因，尤其是在处理小活检材料时。相反，肿瘤不太常见的模式在切除的材料中也可能带来重大诊断问题，鉴别诊断通常包括已知发生在纵隔腔的其他梭形细胞肿瘤。这些肿瘤起源各异，可能与梭形细胞胸腺瘤有重叠的病理特征。由于梭形细胞胸腺瘤主要影响成年人群，且主要起源于前纵隔的胸腺，本综述将重点关注与其他具有相似人口统计学特征且大多起源于前纵隔区室的梭形细胞肿瘤的鉴别诊断。这些包括其他胸腺起源的上皮性梭形细胞肿瘤（肉瘤样胸腺癌和梭形细胞类癌肿瘤）、间叶性肿瘤[孤立性纤维性肿瘤（SFT）、滑膜肉瘤和去分化脂肪肉瘤]以及各种其他具有梭形细胞形态的肿瘤，这些肿瘤偶尔可累及前纵隔。将讨论这些病变的临床、病理、免疫组化和分子特征，并提供与梭形细胞胸腺瘤鉴别诊断的有用提示。
