Adult Solid Alveolar Rhabdomyosarcoma: A Case Report and Literature Review

Abstract

目的：研究成人实体型腺泡状横纹肌肉瘤(alveolar rhabdomyosarcoma, ARMS)的病理学特征、治疗以及鉴别诊断。方法：观察1例实体型腺泡状横纹肌肉瘤的病理学特征及免疫表型，并查阅相关文献。结果：肿物位于左侧腹股沟，肿瘤由实性瘤细胞巢组成，腺泡状结构不明显。部分瘤细胞因富含糖原透明，类似肾透明细胞癌或软组织透明细胞肉瘤，称为透明细胞变型。免疫组化示肿瘤细胞desmin Myoglobin, MyoD1, CD99, CD56均(+), Syn, CgA, Fli-1, LCA, TTF-1, CK, CD20均(−)，瘤细胞Ki-67增殖指数约70%。结论：ARMS是发生自胚胎间叶组织的恶性肿瘤，多发生于四肢深部软组织，形态学上以腺泡状结构为特征，需与恶性淋巴瘤、透明细胞肉瘤、尤文氏肉瘤(ES)/原始神经外胚层肿瘤(PNET)等鉴别。 Objective: To investigate the pathological features, treatment and differential diagnosis of adult solid alveolar rhabdomyosarcoma (ARMS). Methods: The pathological features and immunophenotype of 1 case of solid alveolar rhabdomyosarcoma were observed and the related literatures were consulted. Results: The tumor was located in the left groin, and the tumor con-sisted of solid tumor cell nests with no obvious alveolar structure. Some tumor cells are rich in glycogen, similar to renal clear cell carcinoma or soft tissue clear cell sarcoma, called clear cell variant. Immunohistochemical staining showed that tumor cells desmin, Myoglobin, MyoD1, CD99, CD56 all (+), Syn, CgA, Fli-1, LCA, TTF-1, CK, CD20 all (−), tumor cell Ki-67 proliferation index of about 70%. Conclusion: ARMS is a malignant tumor from embryonic mesenchymal tissue, which occurs in deep soft tissues of the extremities. It is morphologically characterized by a vesicular structure. It needs to be associated with malignant lymphoma, clear cell sarcoma, and Ewing’s sarcoma (ES)/primitive neuroectodermal tumor (PNET) and other identification.